1,2,3-trichloropropane

Endpoint summary

Description of key information

- Repeated dose toxicity, oral: LOAEL = 8 mg/Kg bw for the rat, (OECD 408); study Hazelton (1983)
- Repeated dose toxicity, dermal: no study available
- Repeated dose toxicity, inhalation: NOAEC = 6 mg/m³ (= 1.0 ppm) for the rat, (OECD TG 413); study Monsanto (1983) 

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Comparable to a guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

yes

Remarks:

: 120 day treatment time, interim sacrifice and observation of half of the study groups after 60 days; study according to NTP protocol

Principles of method if other than guideline:

Test substance was administered to F344 rats at 5 days per week for a minimum of 60 calendar days; after interim sacrifice of 10 animals per group per sex, the remaining rats were dosed for a minimum of an additional 60 days and subsequently sacrificed.
Parameters assessed were body weight and body weight gain, hematology, clinical chemistry, urinalysis, organ weights, gross pathology and histopathology.
The study was conducted according to a NTP protocol.

GLP compliance:

yes

Remarks:

according to SIDS report

Limit test:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: NTP Frederick Cancer Research Center (FCRC), Frederick MD, U.S.A.
- Age at study initiation: mean age: 7.5 weeks
- Weight at study initiation: 131-218 g (males); 108-153 g (females)
- Fasting period before study:
- Housing: 5 per cage in polycarbonate cages (10.25"x18.75"x8.5", Hazleton Systems, Aberdeen MD) equipped with heat-treated hardwood chips (P.J. Murphy Forest Product, Mt. Jewuit PA) and a cage filter (Non-woven polyester, duPont "Reemy", National Paper Company, Baltimore MD) in a suspended rack system (Stainless steel, Hazleton Systems, Cincinnati OH).
- Diet (e.g. ad libitum): NIH-07 open formula, powdered (Zeigler Bros., Gardners PA), ad libitum
- Water (e.g. ad libitum):ad libitum
- Acclimation period:15 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-26°C
- Humidity (%): 32-86%
- Air changes (per hr): approximately 10 times/hr
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From:Jan 03 1983 To: Apr 27-29 1983 (interim evaluation); Jun 29-Jul 01 1983

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Dose Preparation and Analysis: The solution was prepared on a w/v basis. For each dose level, the exact amount of chemical (TCP) was weighed out in a glass beaker. Corn oil was then added to the desired volume, followed by mixing on a magnetic stirrer for 2-3 minutes. Fresh solutions were stored in the dark and prepared weekly.


VEHICLE
- Justification for use and choice of vehicle (if other than water): corn oil

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Determination of the free acid (as HCl) conctent was performed by titration with values ranging from 46-48 ppm.
Two successive gas chromatographic analyses (interval: 7 months) exhibited one major peak and three impurities with a combined area of 0.60% of the 1,2,3-trichloropropane peak.
The substance can therefore considered to be stable under the conditions applied.

Duration of treatment / exposure:

The animals were dosed 5 days per week for a minimum of 60 calendar days. After interim sacrifice of 10 animals (or half of survivals) per group per sex, the remaining animals were dosed for a minimum of an additional 60 days.

Frequency of treatment:

5 times per week

Remarks:

Doses / Concentrations:
0, 8, 16, 62, 63, 125, 250 mg/kg
Basis:
other: nominal in vehicle (corn oil)

No. of animals per sex per dose:

Vehicle control: 30 animals per sex
All other doses: 20 animals per sex

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose levels were established by NTP based on available toxicity data.
- Rationale for animal assignment (if not random): The animals were randomized into test and control groups proportionately by weight class. First the animals were randomized into weight groups by sex, then the weight groups were randomized into dose groups. The dose groups were then randomized into the place position on the racks.

Positive control:

no data

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly


BODY WEIGHT: Yes
- Time schedule for examinations: weekly


OPHTHALMOSCOPIC EXAMINATION: No


HAEMATOLOGY: Yes
- Time schedule for collection of blood:prior to the 60 day and 120 day sacrifice
- Anaesthetic used for blood collection: No
- Animals fasted: No
- How many animals: all
- Following parameters were examined: see Table 1

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: prior to the 60 day and 120 day sacrifice
- Animals fasted: No data
- How many animals: all
- Following parameters were examined: see Table 1


URINALYSIS: Yes
- Time schedule for collection of urine:prior to the 60 day and 120 day sacrifice
- Metabolism cages used for collection of urine: Yes
- Animals fasted: No data
- Following parameters were examined: Appearance, specific gravity


NEUROBEHAVIOURAL EXAMINATION: No data

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Other examinations:

Sperm enumeration and morphology

Statistics:

The data from groups of the same sex were evaluated by Bartlett's test for homogeneity of variance (Bartlett, 1937). This analysis was followed by one-way classification analysis of variance (ANOVA) (Miner, 1971) if the variance proved to be homogeneous. If the variances proved to be heterogeneous, a log10 transformation of the original data was performed, followed by Bartlett’s test. If homogeneity could not be achieved by transformation, ANOVA of the non-transformed data was completed. If ANOVA of homogeneous data was significant, Scheffe's (1953) multiple pairwise comparison procedure was used to compare the group mean values. If ANOVA of heterogeneous data was significant, Games and Howel’s (1976) multiple pairwise comparison procedure was used to compare the group mean values. If ANOVA was not significant, no pairwise comparisons were made.
The thymus weights and ratios of the males sacrificed at termination were analyzed by Levenes (1960; Draper and Hunter, 1969) test for homogeneity of variances followed by ANOVA. Group comparisons were performed by Dunnett's t-test (1955 and. 1964) only if ANOVA was significant.
The null hypothesis was rejected only if P < 0.05 (i.e. the 5% level of significance was chosen). One-tailed tests were used in all cases.

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

MORTALITY
All animals died in the 250 mg/kg dose groups.
One male and five female rats died in the 125 mg/kg dose group.
One female control was sacrificed and one rat of the 125 mg/kg male group was missexed and discarded.

CLINICAL SIGNS
Clinical observations attributed to treatment were a thin and hunched appearance, depression, abnormal eyes and urine stains.

BODY WEIGHT AND WEIGHT GAIN
Terminal body weights of male and female rats were significantly lower in the 125 mg/kg dose group compared to the control group at 60- and 120-day sacrifices.
All the test groups showed weight gain depression.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
Food consumption was depressed in the 250 mg/kg group during the few weeks measurable.

HAEMATOLOGY
There was a chemical dose-dependent pattern of decreased mean hematocrit, haemoglobin and erythrocyte counts in both sexes in the 16, 32, 63, and 125 mg/kg dose levels noted at the 60- and 120-day sacrifice. The mean leukocyte count was slightly decreased in the 125 mg/kg male group at the 120-day interval.

CLINICAL CHEMISTRY
The clinical chemistry results indicate hepatocellular damage and coincide with the histopathological findings for the liver. In general, the trends observed at the 60-day interval were also evident following 120 days of compound administration. Changes observed were significant for liver profile and indicated hepatocellular damage. In males at 63 and 125 mg/kg there were decreased pseudocholinesterase and BUN. In females SGOT, SGPT and SDH were significantly increased at 16 mg/kg and greater, except for BUN, which was decreased at 32, 63 and 125 mg/kg. Also, total bilirubin was increased in females at 125 in males and at 63 and 125 in females.

URINALYSIS
No compound-related effects.

ORGAN WEIGHTS
At 120 days (terminal sacrifice), there were statistically significant increases in
(1) liver weight in all dosed males and at 16, 32, 63 and 125 mg/kg females, and
(2) kidney weight in 32 and 125 mg/kg males and 63 mg/kg females.
The significant relative organ weight changes included:
(1) lower testes weight at 125 mg/kg,
(2) increased brain (125 mg/kg females), lung (125 mg/kg males), liver (all dosed males and females at 16, 32, 63 and 125 mg/kg ), kidney (32 and 125 mg/kg males, and 32, 63 and 125 mg/kg females). Organ to brain weight ratios showed the same trend for liver and kidney


GROSS PATHOLOGY
No treatment-related changes were visible on the sacrificed animals.
Gross necropsy of the deaths and moribund sacrifices revealed reddening of the stomach and dark or reddened renal medullas as a common finding in the 250 mg/kg animals.

HISTOPATHOLOGY: NON-NEOPLASTIC
Treatment related changes were observed primarily in the liver (females), kidneys and nasal turbinates (males/females).
Liver: Hepatotoxicity observed in females at 125 mg/kg consisted of focal or multifocal necrosis, necrosis of individual hepatocytes, the presence of sinusoidal pigment and bile duct chronic inflammation and hyperplasia.
Kidneys: Tubular regenerative hyperplasia and hyperbasophilia, megalocytosis of diffusely scattered individual tubular epithelial cells, proteinaceous tubular casts and increase in severity of chronic progressive nephropathy at 125 mg/kg; at 63 mg/kg there was an increased incidence of chronic progressive nephropathy primarily in males.
Nasal Turbinates: at 125 mg/kg only there were foci of mucosal necrosis or necrosis of individual epithelial cells, chronic inflammatory change and attenuation of the epithelial lining, primarily the dorsal posterior region of the turbinates. Occasional males had foci of necrosis of turbinates.

Dose descriptor:

NOAEL

Sex:

male

Basis for effect level:

other: organ weight effects in all doses (absolute and relative liver weight increase)

Remarks on result:

not determinable

Remarks:

no NOAEL identified

Dose descriptor:

NOAEL

Effect level:

8 mg/kg bw/day (nominal)

Sex:

female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

yes

Lowest effective dose / conc.:

8 mg/kg bw/day (nominal)

System:

other: uronary, hepatobiliary

Organ:

kidney

liver

Treatment related:

yes

Dose response relationship:

yes

Relevant for humans:

not specified

Table 2: Final Body Weight, Weight Gain and Test Groups Weight Gain % Different from Control

	Male				Female
Dose level mg/kg	BW at start	BW at Wk 17	Gain in Grams	Body Gain Wt % Gain from Control	BW at start	BW at Wk 17	Gain in Grams	Body Gain Wt % Gain from Control
Control	180	389	209		128	216	88
8	174	393	219	+4.78	129	216	87	-1.14
16	185	372	187	-10.53	132	225	93	+5.68
32	177	386	209	0.00	127	215	88	0.00
63	181	345	164	-21.53	129	208	79	-10.23
125	179	306	127	-39.23	130	165	35	-60.23
250	176	132*	-44		127	106**	-21

* All the animals died – Weight for Week 4 based on one survivor

** All the animals died – Weight for Week 1 based on four survivors

 

 

Table 3: Mean Terminal Body Weights, Organ Weights, Organ/Body Weight Ratios (Day 120) - Male

Dose level mg/kg		Final Body Wt. (g)	Brain		Lungs		Kidneys		Testes
			(G)	Ratio %	(G)	Ratio %	(G)	Ratio %	(G)	Ratio %
Control	Mean S.D. N=	361.00 17.664 10	2.0180 .06460 10	.5605 .03847 10	1.312 .0946 10	.364 .0257 10	1.081 .0524 10	.300 .0096 10	1.534 .0743 10		.425 .0128 10
8	Mean S.D. N=	366.90 22.243 10	1.9670 .08354 10	.5373 .03051 10	1.281 .1041 10	.349 .0215 10	1.090 .0622 10	.297 .0139 10	1.609 .1173 10		.439 .0218 10
16	Mean S.D. N=	351.10 33.985 10	1.9410 .06935 10	.5566 .04423 10	1.209 .1019 10	.345 .0183 10	1.102 .1056 10	.314 .0139 10	1.476 .1252 10		.423 .0409 10
32	Mean S.D. N=	368.20 13.481 10	2.0010 .03635 10	.5440 .01723 10	1.341 .1291 10	.364 .0307 10	1.242** .0535 10	.337* .0079 10	1.630 .0793 10		.443 .0177 10
63	Mean S.D. N=	308.30** 46.164 10	1.9380 .02394 10	.6438 .11367 10	1.189** .0615 10	.396 .0821 10	1.133** .0672 10	.377** .0762 10	1.54 .02 9		.493** .1107 9
125	Mean S.D. N=	278.67** 25.348 9	1.924** .11359 9	.6993** .11471 9	1.140** .0723 9	.411* .0343 9	1.280** .0598 9	.463** .0468 9	1.518 .1565 9		.547** .0577 9

* Significantly different (P<=0.05) from the control group by Williams' or Dunnett's test

** P<=0.01

 

Table 3 (cont.): Mean Terminal Body Weights, Organ Weights, Organ/Body Weight Ratios (Day 120) – Male

Dose level mg/kg		Final Body Wt. (g)	Heart		Liver		Thymus		Epididymides
			(G)	Ratio %	(G)	Ratio %	(G)	Ratio %	(G)	Ratio %
Control	Mean S.D. N=	361.00 17.664 10	1.042 .0535 10	.289 .0215 10	8.869 .4314 10	2.461 1.597 10	.281 .0221 10	.078 .0083 10	.518 .0564 10		.144 .0192 10
8	Mean S.D. N=	366.90 22.243 10	1.036 .1540 10	.284 .0507 10	9.821** .6783 10	2.679 .1394 10	.236 .0562 10	.064 .0146 10	.516 .0493 10		.141 .0137 10
16	Mean S.D. N=	351.10 33.985 10	.934 .0891 10	.266 .0159 10	9.716** 1.1961 10	2.763 .1408 10	.222 .0424 10	.064 .0141 10	.477 .0316 10		.137 .0145 10
32	Mean S.D. N=	368.20 13.481 10	1.002 .0343 10	.272 .0100 10	11.199** .6441110	3.045** .2077 10	.254 .0657 10	.069 .0178 10	.511 .0166 10		.139 .0057 10
63	Mean S.D. N=	308.30 46.164 10	.904** .0580 10	.300 .0576 10	10.926** .7292 10	3.617** .5908 10	.220 .0748 10	.071 .0201 10	.474 .0379 10		.157 .0289 10
125	Mean S.D. N=	278.67 25.348 9	0.82** .02 9	.296** .007 9	12.066** .3962 9	4.366** .4823 9	.272 .1994 9	.096 .0686 9	.496 .1769 9		.177 .0597 9

* Significantly different (P<=0.05) from the control group by Williams' or Dunnett's test

** P<=0.01 

 

Table 4: Mean Terminal Body Weights, Organ Weights, Organ/Body Weight Ratios (Day 120) - Female

Dose level mg/kg		Final Body Wt. (G)	Brain		Lungs		Heart		Liver
			(G)	Ratio %	(G)	Ratio %	(G)	Ratio %	(G)	Ratio %
Control	Mean S.D. N=	199.80 9.473 10	1.8090 .04932 10	.9067 .03596 10	.968 .0983 10	.485 .0517 10	.666 .0417 10	.334 .0217 10	5.141 .3205 10		2.574 .1135 10
8	Mean S.D. N=	199.90 11.030 10	1.7990 .04748 10	.9029 .06485 10	.971 .0500 10	.487 .0407 10	.654 .0420 10	.328 .0298 10	5.494 .2783 10		2.755 .1930 10
16	Mean S.D. N=	210.00 17.378 10	1.8240 .06687 10	.8729 .06501 10	.936 .0840 10	.447 .0328 10	.674 .0859 10	.320 .0256 10	6.067** .5013 10		2.892** .1392 10
32	Mean S.D. N=	199.40 11.237 10	1.1860 .06769 10	.9126 .04706 10	.929 .0739 10	.466 .0218 10	.617 .0529 10	.309 .0189 10	6.004* .2829 10		3.018** .1874 10
63	Mean S.D. N=	193.00 9.649 10	1.8290 .14587 10	.9500 .09435 10	.946 .1710 10	.490 .0870 10	.656 .0882 10	.341 .0496 10	6.785** .5362 10		3.517** .2381 10
125	Mean S.D. N=	158.00** 14.900 6	1.7233 .17963 5	1.0934** .08871 5	.800** .0261 6	.509 .0376 6	.608 .1613 6	.383 .0762 6	8.248** .4781 6		5.257** .5508 6

* Significantly different (P<=0.05) from the control group by Williams' or Dunnett's test

**P<=0.01

 

Table 4 (cont.): Mean Terminal Body Weights, Organ Weights, Organ/Body Weight Ratios (Day 120) - Female

Dose level mg/kg		Final Body Wt. (G)	Kidneys		Thymus
			(G)	Ratio %	(G)	Ratio %
Control	Mean S.D. N=	199.80 9.473 10	.637 .0424 9	.316 .0195 9	.174 .0194 10	.087 .0112 10
8	Mean S.D. N=	199.90 11.030 10	.670 .0863 10	.337 .0600 10	.194 .0443 10	.097 .0205 10
16	Mean S.D. N=	210.00 17.378 10	.709 .0498 10	.338 .0185 10	.213 .0584 10	.101 .0219 10
32	Mean S.D. N=	199.40 11.237 10	.697 .0552 10	.349 .0162 10	.198 .0282 10	.099 .0145 10
63	Mean S.D. N=	193.00 9.649 10	.803** .1034 10	.416** .0544 10	.180 .0371 10	.093 .0170 10
125	Mean S.D. N=	158.00 14.900 6	.710** .0490 6	.452** .0460 6	.215^a .1754 6	.137^b .1129 6

a= Deletion of two apparently incorrect weights (recording errors) resulted in mean = 0.105, S.D. = 0.0540, N=4.

b= Recalculation of ratio following deletion of two weights resulted in mean = 0.066, S.D. = 0.0293, N=4.

* Significantly different (P<=0.05) from the control group by Williams' or Dunnett's test

** P<=0.01 

Conclusions:

A clear NOAEL was not demonstrated for males, based upon statistically significant increases in liver weight in all treatment groups.
The NOAEL in females was 8 mg/kg/d.

Executive summary:

The toxicity of 1,2,3 -trichloropropane after repeated dose administration was assessed in male and female F344 rats in a 120 day study (gavage). The results show a subchronic toxicity of 1,2,3 -trichloropropane at 8 mg/kg/day (males), which is the lowest concentration tested, and at 16 mg/kg/d (females). In consequence, no NOAEL could be derived for the male rats whereas the NOAEL for subchronic exposure of female rats was 8 mg/kg/d.

1,2,3 -Trichloropropane led to early mortality in males and females at the 250 mg/kg dose level. Deaths resulted from renal and hepatic toxicity and necrosis with subsequent inflammatory change in the dorsal posterior nasal mucosa. The pathogenesis of the nasal mucosa induced lesions is not fully understood. Changes observed in animals dying after as few as two dosings were peracute and consisted of mucosal coagulative necrosis specifically of the dorsal posterior aspect of the nasal passages. This may suggest a local effect, rather than a systemic effect, possibly resulting from small amounts of residual compound in the pharynx after dosing or escape of volatile material from the stomach into the nasal passages.

Animals sacrificed after 60 days at the 125 mg/kg dose level had hepatic clinical chemistry alterations with histologic evidence of hepatotoxicity as well as renal toxicity and histomorphologic alterations of the dorsal posterior nasal mucosa. Histomorphologic renal and nasal changes were observed in males and females at the 63 mg/kg level. All but the 8 mg/kg dose and control groups had decreased red cell mass. A statistically significant difference (negative trend) in the testes weight ratios and epididymal weight ratios were observed in the 125 mg/kg male group, but no histomorphologic change was observed.

Rats sacrificed at termination (120 days) of the study from the 125 mg/kg dose group had a dramatic reduction in the rate of weight gain and this was observed to a lesser extent in the 63 mg/kg group. Decreased red cell mass was observed in males and females at the 125 and 63 mg/kg levels. Treatment-related clinical chemistry alterations were observed in males receiving doses of 125 and 63 mg/kg. Females appeared more sensitive to treatment, having alterations in several parameters at doses of 125, 63, 32 and, to a lesser extent, at the 16 mg/kg level. Treatment-related histmorphologic alterations at the terminal sacrifice at the 125 mg/kg consisted primarily of tubular nephrotoxicity, hepatotoxicity in female rats and changes in the dorsal posterior nasal mucous similar to those observed at the 60-day sacrifice. Examination of target organs at the 63 and 32 mg/kg levels only revealed changes in the kidneys of animals receiving doses of 63 mg/kg.

Reference 2

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: - scientifically sound study, according to OECD 408 - journal publication presenting only limited numerical results

Qualifier:

according to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Principles of method if other than guideline:

in addition the results from a 10 d dose range finder study are included

GLP compliance:

not specified

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles Rivers Laboratories, Inc. Portage, MI, U.S.A.
- Age at study initiation: 70 d at arrival, 80 at start of administration
- Weight at study initiation: not reported
- Fasting period before study: no
- Housing: housed in polycarbonate cages containing hardwood chip bedding (Absorb-Dri, Maywood, NY),no. of animals per cage not reported
- Diet (e.g. ad libitum): ad libitum with Purina Rodent Chow (No. 5001, Ralston Purina Co., St. Louis, MO)
- Water (e.g. ad libitum): distilled drinking water that had been carbon-filtered and UV-irradiated
- Acclimation period: 10 d


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-22
- Humidity (%): 40-60
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: 1,2,3-trichloropropane was dissolved in corn oil at 1 mL/kg.

VEHICLE
- Justification for use and choice of vehicle (if other than water): corn oil is a standard vehicle for organic solvents
- Concentration in vehicle: 90 d study: 0.01, 0.05, 0.1 and 0.4 mol/L (= 1.47, 7.37, 14.74, 58.97 g/L)
10 d study: 0.01, 0.05, 0.2 and 0.8 mol/L (= 1.47, 7.37, 29.49, 117.94 g/L)
- Amount of vehicle (if gavage): 1 mL/Kg
- Provider: Sigma Chemical Company (St. Louis, MO, U:S.A.)

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

no data

Duration of treatment / exposure:

10d and 90d,

Frequency of treatment:

single daily exposure via gavage

Remarks:

Doses / Concentrations:
0.01, 0.05, 0.1 and 0.4 mmol/Kg bw (= 1.47, 7.37, 14.74, 58.97 mg/Kg bw)
Basis:
other: nominal via gavage in the 90 d study

Remarks:

Doses / Concentrations:
0.01, 0.05, 0.2 and 0.8 mmol/Kg bw (= 1.47, 7.37, 29.49, 117.94 mg/Kg bw)
Basis:
other: nominal via gavage in the 10 d study

No. of animals per sex per dose:

not reported

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: 10 d range finding study: high dose selected as one-quarter of the reported acute oral dose of 440 mg/Kg/d (= 3.0 mmol/Kg bw); 90 d study: based on the results of the 10 d study 0.4 was selected as the high dose
- Rationale for animal assignment (if not random): random

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: No data


DETAILED CLINICAL OBSERVATIONS: No data


BODY WEIGHT: Yes
- Time schedule for examinations: 90 d study: weekly; 10 d study: prior to first dosing and at sacrifice


FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): No


FOOD EFFICIENCY: No


WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
- Time schedule for examinations: twice weekly


OPHTHALMOSCOPIC EXAMINATION: No data


HAEMATOLOGY: No data

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at terminal sacrifice
- Anaesthetic used for blood collection: Yes (60 mg/Kg Nembutal (Abbott Las, Chicago, IL, U.S.A.)
- Animals fasted: No
- How many animals: all
- Parameters examined: not reported in detail, at least ALT, AST, BUN and creatinine


URINALYSIS: No


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, see below
HISTOPATHOLOGY: Yes, see below
organ weights + lights microscopy: liver, kidneys, lung, spleen, heart, adrenal glands, thymus and brain
histopathology: analysis of high dose and controls; low and mid dose only for tissues where adverse effects were seen in the high dose group
liver, kidneys, lung, spleen, heart, adrenal glands, thymus, brain, alimentary canal (tongue, esophagus, stomach, duodenum,
jejunum, ileum, caecum, colon and rectum), femur bone, mandibular and mesenteric lymph nodes, mammary glands, thigh muscle, nasal cavity, sciatic nerve, ovaries, pancreas, parathyroids, pituitary, preputial or clitoral glands, prostate, salivary glands, seminal vesicles, skin, testis and epididymis, thyroid gland, urinary bladder, uterus, Zymbal's glands and all gross lesions.
- femurs and nasal structures decalcified prior to trimming and fixation
- grading from 1 - 4 of the severity of inflammatory, degenerative and necrotic lesions in tissuesd.
Histopathological evaluation was performed by a board-certified veterinary pathologist (Pathology Associates Inc., Ijamsville, MD).

Statistics:

- analysis of variance (ANOVA), with differences between control and 1,2,3-TCP-treated groups evaluated by Duncan's multiple comparison
tes
- not normally distributed data: Wilcoxin Rank Sum test for treatment differences and the Kruskal-Wallis Rank Sums test for differences among means.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

effects observed, treatment-related

Details on results:

CLINICAL SIGNS AND MORTALITY
- no mortalities or adverse clinical signs reported

BODY WEIGHT AND WEIGHT GAIN
- reduced body weight gain in the males and females of the high dose groups both in the 10 d and the 90 d study
- see table 1

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
not examined

FOOD EFFICIENCY
not examined

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study)
not effects detected

OPHTHALMOSCOPIC EXAMINATION
not examined

HAEMATOLOGY
- slightly reduced white blood cell count in males after the 10-day exposure but no such effect in females or any of the dose groups in the 90 d study

CLINICAL CHEMISTRY
- 10 d study: significantly increased ALT and AST values at the high dose
- 90 d study: significantly raised ALT and AST levels at the high dose in female rats only, raised values in males were compromised by very high ALT and AST levels in male controls, mirrored by histopathological findings in this control group

URINALYSIS
not examined

NEUROBEHAVIOUR
not examined

ORGAN WEIGHTS
- absolute organ weights:
heart, spleen, thymus and lung weight reduction in the high doses of both sexes of both studies
- relative organ weights:
generally no differences in relative weights of heart, lung and spleen (and ovaries in females)
relative thymus weight decreased in the high dose groups of both sexes in the 10 d study (but not in the 90 d study)
generally raised relative liver and kidney weights in the two highest doses groups in both sexes in both studies.
effects in the relative brain weights were explained by the reduced body weights in the high dose groups


GROSS PATHOLOGY
no macroscopically visual changes reported

HISTOPATHOLOGY: NON-NEOPLASTIC
- heart:
diffuse inflammation-associated necrosis of cardiac myocardiumin both sexes in all treatment groups in the 90 d study but only in the high dose group in the 10 d study. The prevalence for males was higher then for females. There is no clear dose response to this effect. (see table 2). The severity of cardiac lesions is reported to increase dose dependently (no detailed values given).
This cardiac lesions were reported by the authors to occur also in Long Evans rats and F344 rats if treated for 10 d at 0.8 mmol/Kg bw/d (high dose of the 10 d study).
- thymus:
atrophy in the high doses groups of both sexes in the 10 d study, no effects in the 90 d study
- liver:
10 d study: mild centrilubolar hepatic necrosis in one female and two males of the high dose
90 d study:
females: minimal liver necrosis in one animal in the 0.05 mmol/Kg dose group and in two animals of the high dose group
males: mild to moderate liver necrosis with increasing dose related incidence (1 - 4) in the respective dose groups. The findings were confounded by mild hepatic lesions in four of the male control animals


HISTOPATHOLOGY: NEOPLASTIC (if applicable)
- increased prevalence of bile duct hyperplasia in both sexes in the high dose group in the 90 d study
- plasma cell hyperplasia in the mandibular lymph nodes at variable extent in control males and females, but increased incidence in males exposed to high dose after 10 days; in the 90 d study a dose dependently increased prevalence of mandibular lymph node hyperplasia was found for both sexes
- No lesions in mesenteric, subcutis, pancreatic, bronchiolar or mediastinal lymph nodes
subchronic exposure conditions.
- Several other proliferative and neoplastic lesions in individual animals at high dose treatment: broncho-alveolar adenoma in a male, an adenocarcinoma of a female mammary gland, a forestomach squamous cell papilloma in a male and forestomach squamous cell hyperplasia in a male.

Dose descriptor:

NOAEL

Sex:

male/female

Basis for effect level:

other: at the lowest dose in the 90 d study inflammation and necrosis in the heart was seen. Nevertheless no clear dose response could be seen for this effect neither in males nor females.

Remarks on result:

not determinable

Remarks:

no NOAEL identified

Critical effects observed:

yes

Lowest effective dose / conc.:

1.47 mg/kg bw/day (actual dose received)

System:

cardiovascular

Organ:

heart

Treatment related:

yes

Dose response relationship:

no

Relevant for humans:

not specified

- Table 1: Final body weights of rats after subacute and subchronic exposure to 1,2,3 -trichloropropane

	Dose mmol/kg/day)	Body weight (g) after 10-day exposure	Dose (mmol/kg/day)	Body weight (g) after 90-day exposure
Male
	0.00	451 ± 8	0.00	529 ± 13
	0.01	410 ± 13	0.01	528 ± 16
	0.05	436 ± 7	0.05	509 .±. 11
	0.20	417 ± 8	0.10	533 ± 16
	0.80	337 ± 12*	0.40	426 ± 13*
Female
	0.00	253 ± 4	0.00	301 ± 5
	0.01	256 ± 3	0.01	301 ± 9
	0.05	262 ± 4	0.05	307 ± 10
	0.20	260 ± 3	0.10	301 ± 6
	0.80	195 ± 6*	0.40	258 ± 7*

Body weights were measured on the day of sacrifice. Values represent means ± SEM for 10 rats per group. An asterisk indicates means that are significantly different from the control value at P < 0.05.

- Table 2: Incidence of organ histopathology of rats after subacute and subchronic exposure to 1,2,3 -trichloropropane

Target organ	Male					Female
mmol/kg/day x 10 days
	0.00	0.01	0.05	0.20	0.80	0.00	0.01	0.05	0.20	0.80
Heart
Inflammation	1	0	0	0	10	0	0	0	0	10
Degeneration	0	0	0	0	10	0	0	0	0	10
Necrosis	0	0	0	0	10	0	0	0	0	10
Mandibular lymph	4	-	-	-	7	1	-	-	-	0
node
Thymus Diffuse atrophy	0	0	0	0	6/8	0	0	0	0	6/6
mmol/kg/day x 90 days
	0.00	0.01	0.05	0.10	0.40	0.00	0.01	0.05	0.10	0.40
Heart
Inflammation	0	3	2	3	8	0	1	2	1	6
Degeneration	0	0	0	1	5	0	0	1	1
Necrosis	0	2	1	2	6	0	0	1	0	7
Liver
Bile duct	1	0	0	0	4	0	0	0	0	8
hyperplasia .,...
Mandibular lymph node	2	0	1	0	9	1	1	2	3	5

Tissues were prepared for histological evaluation by staining with hematoxylin and eosin. Tissues of 10 animals were evaluated for each dose group unless otherwise indicated. A dash means that the tissues were not evaluated.

Conclusions:

The toxicity of 1,2,3-trichloropropane was tested in Sprague Dawley rats in a 90 d repeated dose study with oral treatment via gavage (5 d/wk). Results for a 10 d dose range finding experiment are included.
A NOAEL cannot be defined as a raised prevalence of inflammation-associated diffuse necrosis of the cardiac myocardium was seen in all dose groups of the 90 d experiment but with an uncommon dose response pattern. In addition slight renal and liver weight effects and corresponding clinical chemical and histological findings in the liver were determined in the two highest dose groups of the 90 d study. As neoplastic lesions a significant increase in bile duct hyperplasia above the age related background was reported and a higher incidence of adenoma papilloma and carcinoma scattered over different tissues.

Executive summary:

In the present study (Merrick 1991) the toxicity of 1,2,3-trichloropropane was tested in Sprague Dawley rats in a 90 d repeated dose study with oral treatment via gavage (5 d/wk) according to OECD TG 408. Results for a 10 d dose range finding experiment are included.

A NOAEL could not be derived from the reported results as a raised prevalence of inflammation-associated diffuse necrosis of the cardiac myocardium was seen in all dose groups of the 90 d experiment but with an uncommon dose response pattern.

Animals aged 80 d at study initiation were treated with 1,2,3 -trichloropropane in corn oil, weighted weekly and their water consumption was determined twice weekly. At terminal sacrifice blood samples were taken for clinical chemical analysis and hematology. These animals were subjected to gross necroscopy and full histological examination.

No mortalities and adverse clinical signs were reported. Reduced body weight gain was found in the males and females of the high dose groups both in the 10 d and the 90 d study. No treatment related effects were seen regarding water consumption of treated animals as compared to controls. Hematologic examination revealed a slightly reduced white blood cell count in males after the 10-day exposure but no such effect in females or any of the dose groups in the 90 d study, therefore this finding is regarded as incidental. For the 10 d study: significantly increased ALT and AST values at the high dose are reported. Accordingly also in the 90 d study significantly raised ALT and AST levels at the high dose in female rats only were determined. Raised values in males of the 90 d study were compromised by very high ALT and AST levels in male controls, mirrored by histopathological findings in this control group. Several absolute organ weights are reduced (heart, spleen, thymus and lung) in the high doses of both sexes of both studies but as the body weights are reduced in these groups the more relevant relative organ weights of heart, lung and spleen (and ovaries in females) showed generally no differences. Nevertheless the relative thymus weight was decreased in the high dose groups of both sexes in the 10 d study (but not in the 90 d study) and generally raised relative liver and kidney weights in the two highest doses groups in both sexes in both studies were reported. Effects in the relative brain weights were explained by the reduced body weights in the high dose groups.

Several non-neoplastic lesions were revealed by the histologic examination, the most prominent being found in the heart as diffuse inflammation-associated necrosis of cardiac myocardiumin both sexes in all treatment groups in the 90 d study but only in the high dose group in the 10 d study. The prevalence for males was higher then for females and there is no clear dose response to this effect. The severity of cardiac lesions is reported to increase dose dependently (no detailed values given). This cardiac lesions were reported by the authors to occur also in Long Evans rats and F344 rats if treated for 10 d at 0.8 mmol/Kg bw/d (high dose of the 10 d study).

In thymus atrophy in the high doses groups of both sexes in the 10 d study is reported, but no effects in the 90 d study, therefore this effect is not regarded as adverse. For the liver mild centrilubolar hepatic necrosis in one female and two males of the high dose was detected in the 10 d study. In the 90 d study in females minimal liver necrosis in one animal in the 0.05 mmol/Kg dose group and in two animals of the high dose group was found while in males mild to moderate liver necrosis with increasing dose related incidence (1 - 4) in the respective dose groups was detected. The latter findings were confounded by mild hepatic lesions in four of the male control animals.

Several indications for preneoplastic lesions were also noted as there are an increased prevalence of bile duct hyperplasia in both sexes in the high dose group in the 90 d study, plasma cell hyperplasia in the mandibular lymph nodes at variable extent in control males and females, but increased incidence in males exposed to high dose after 10 days plus in the 90 d study a dose dependently increased prevalence of mandibular lymph node hyperplasia.

Other proliferative and neoplastic lesions in individual animals at high dose treatment comprised broncho-alveolar adenoma in a male, an adenocarcinoma of a female mammary gland, a forestomach squamous cell papilloma in a male and forestomach squamous cell hyperplasia in a male.

No lesions in mesenteric, subcutis, pancreatic, bronchiolar or mediastinal lymph nodes subchronic exposure conditions.

A derivation of a NOAEL or a LOAEL is not possible for the 90 d study. All adverse effects occur at the highest dose with two exceptions. Firstly relative weight effects in the liver and liver enzyme effects are seen also at the second highest dose (0.1 mmol/Kg/d = 14.74 mg/Kg/d) but these effects are confounded by a uncommon mild liver necrosis in 4 of the control animals. Secondly a significant prevalence of inflammation-related degeneration and necrosis of cardiac myocardium was seen in males of the high dose and to a lesser extent in the females of this dose level. In both sexes there is no clear dose response: 3/10 males showing inflammation at 0.01 mmol/Kg/d, 2/10 at 0.05, 3/10 at 0.1 and 8/10 at 0.4. The respective prevalences for females are 1/10, 2/10, 1/10 and 8/10.

Prevalences of degeneration and necrosis show a comparable variability.

Using the concept of LOAEL and NOAEL strictly would imply a to set the LOAEL for this study to the lowest dose (0.01 mmol/Kg/d = 1.47 mg/Kg bw/d). Nevertheless the complete absence of cardiac effects in a 120 d gavage study and even a 2 year chronic gavage study at comparable dose levels (see chapter 7.5.1: Hazleton (1983) / key (120d study on F344 rats) (8 - 250 mg/Kg bw/d) and chapter 7.7: National Toxicology Program (1993) / Rat and Mouse (3 - 30 and 6 - 60 mg/Kg bw/d, respectively)) renders the correlation between the cardiopathic effects and the 1,2,3 -trichloropropane exposition questionable.

Reference 3

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: - short summary of study - no individual data - scientifically sound study as far as assessable

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

no

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Route of administration:

oral: drinking water

Vehicle:

other: emulphor 0.5%

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

90 d

Frequency of treatment:

permanent in drinking water

Remarks:

Doses / Concentrations:
1, 10, 100 and 1000 mg/L
Basis:
nominal in water

No. of animals per sex per dose:

10

Control animals:

yes, concurrent no treatment

yes, concurrent vehicle

Dose descriptor:

NOAEL

Effect level:

100 mg/L drinking water

Sex:

male/female

Basis for effect level:

other: no adverse affects in any analysed parameter, increased relative liver and kidney weights in female rats at 100 mg/L were in absence of any histological findings in this dose group considered to be not adverse

Dose descriptor:

LOAEL

Effect level:

1 000 mg/L drinking water

Sex:

male/female

Basis for effect level:

other: adverse effects in body weight gain, clinical chemical parameters, hematology, relative kidney and liver weights, and histological findings in liver kidney and thyroid

Critical effects observed:

not specified

- Mortality: three animals died during the study, but were not related to treatment.

- Body weight development:

decreased growth rate was observed in both sexes of the group receiving 1000 mg/L 1,2,3 -trichloropropane, see Table 1 below

- Water intake:

water intake data was significantly different from the vehicle control group in the male high dose group and the female 100 mg/L and the high dose group (1000 mg/L), results are summarized in Table 1 below

- Organ weights: increase in liver, kidney and brain weights (relative to body weight) in rats of both sexes fed 1000 mg/L and in kidneys and livers of the female 100 mg/L group

livers:

males (in % of bw): control, 3.7; vehicle control, 3.7; 1000 mg/L, 4.5

females (in % of bw): control, 3.6; vehicle control, 3.6; 100 mg/L, 3.8; 1000 mg/L, 4.2

kidneys:

males (in % of bw): control, 0.33; vehicle control, 0.32; 1000 mg/L, 0.42

females (in % of bw): control, 0.36; vehicle control, 0.35; 100 mg/L, 0.40; 1000 mg/L, 0.47

- Clinical chemistry

elevation in serum cholesterol was observed in female rats fed the highest dose of 1,2,3-trichloropropane

elevation of hepatic aminopyrine demethylase and aniline hydroxylase activities in male rats at the highest dose.

- Histology: only at the highest dose

liver:

histological changes consisting of an increase in cytoplasmic eosinophilia in the periportal area together with vesiculation of biliary epithelial nuclei. Morphological changes were characterized by increased anisokaryosis in the proximal epithelium and occasional pyknosis associated with the accumulation of large eosinophilic inclusions.

kidneys:

histological changes consisting of eosinopilic inclusions, pyknosis, nuclear displacement, fine glomerular adhesions and occasionally interstitial reactions and histologic proteinuria

Thyroid:

histological changes consisting of angular collapse of some follicles, reduction in colloid density and increased epithelial height

- Table 1: Body weight gain and water intake data

Treatment Group	Initial Weight (g)	Weight Gain (g)	Water Intake (ml/day)	Amount of Chemical Ingested (mg/kg/day)
Control           (M)	79	455	53	-
Vehicle control(M)	76	450	45	-
1,2,3-TCP 1000 mgil. (M)	86	309a,b	27a,b	113
Control           (F)	79	192	44	-
Vehicle Control           (F)	73	207	36	-
1,2,3-TCP 100 mg/L (F)	79	181	31a	17.6
1,2,3-TCP 1000 mg/L (F)	81	140,b	23a,b	149

a Signifies significant difference from control group (K0.05)

b Signifies significant difference from vehicle control group (K0.05)

M denotes male

F denotes female

Conclusions:

1,2,3-trichloropropane is toxic to the liver, the kidneys and the thyroid of rats after repeated subchronic (90 d) application via the drinking water. The deduced NOAEL is 100 mg/L and the corresponding LOAEL is 1000 mg/L.

Executive summary:

A 90-day feeding study in rats was carried out in order to determine the subchronic toxicity of 1,2,3 -trichloropropane via the oral route in drinking water. Groups of 10 male and 10 female weanling Sprague-Dawley rats were supplied drinking water ad libitum, containing 1,2,3-trichloropropane at concentrations of 1, 10, 100 or 1000 mg/L for 13 weeks. Emulphor (0.5%) was used to solubilize the chemicals. Based on the presented results a NOAEL of 100 mg/L and a corresponding LOAEL of 1000 mg/L can be deduced.

At the end of the study, the animals were killed and examined for gross and microscopic changes. Heart, liver, brain, kidney and spleen were excised and weighed. Blood was collected and subjected to a comprehensive hematological analysis. Serum was collected and profiled for changes in 12 biochemical parameters and a portion of liver was used to determine mixed function oxidase activity. Although three animals died during the study, their deaths could not be related to treatment. Decreased growth rate was observed in both sexes of the group receiving 1000 mg/L 1,2,3-trichloropropane. There was an increase in liver, kidney and brain weights (relative to body weight) in rats of both sexes fed 1000 mg/L 1,2,3-trichloropropane. Fatty livers were observed in some of the treated animals but a clear dose-relationship was not evident. An elevation in serum cholesterol was observed in female rats fed the highest dose of 1,2,3-trichloropropane. This chemical also induced hepatic aminopyrine demethylase and aniline hydroxylase activities in male rats at the highest dose. Administration of both isomers produced only mild histological changes in the liver, thyroid and kidney of rats at the highest dose. The changes in the liver consisted of an increase in cytoplasmic eosinophilia in the periportal area together with vesiculation of biliary epithelial nuclei. Morphological changes were characterized by increased anisokaryosis in the proximal epithelium and occasional pyknosis associated with the accumulation of large eosinophilic inclusions. Changes in the thyroid consisted of a mild reduction in follicular size associated with an increased epithelial height. In general, these changes were more severe in the males than females, but were still mild overall.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LOAEL

8 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

16/01/1984 - 19/05/1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: - scientifically sound study - guideline compliant - only 14 d, limited amount of clinical chemical and hematology parameters tested

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)

Deviations:

yes

Remarks:

: limited haematologic, biochemical and urinary examinations

GLP compliance:

yes

Limit test:

no

Species:

other: rat and mouse

Strain:

other: Fischer 344 rats and B6C3F1 mice

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc. (Kingston, NY and Portage, MI, U.S.A. )
- Age at study initiation: 6-8 wk
- Weight at study initiation: rats: 146.9 g (male), 127.4 g (male); mice: 19.1 g (male), 16.3 g (male)
- Fasting period before study: not reported
- Housing: housed singly in stainless steel cages with wire bottoms
- Diet (e.g. ad libitum): Purina Certified Rodent Chow (Ralston Purina Co., St . Louis, MO), ad libitum
- Water (e.g. ad libitum): tap water, analyzed periodically by the City of Midland, MI
- Acclimation period: 12 d

g (male)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.2
- Humidity (%): 50
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 16/01/1984, start of exposure To: 28/01/1984

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: not applicable

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: 4.1 m³ stainless steel and glass chambers
- Method of holding animals in test chamber: Exposures were conducted in the same cages used for housing the animals.
- Source and rate of air: 800 L/min;
- Method of conditioning air: air supplied to the chambers controlled by a system designed to maintain temperature at approximately 21°C and relative humidity at approximately 50%; temperature and relative humidity recorded at the end of each exposure period.
- System of generating vapour:
metering the liquid test material at controlled rates into vaporization tubes as described by Miller et. al. (Miller , R. R., Letts, R. L.. Potts, W. J. and McKenna, M. J. (1980). Improved methodology for generating controlled test atmospheres. Am. Ind. Hyg. Assoc. J. 41:844-846.).
Vapors swept into the exposurechamber inlet ducts with compressed air and mixed and diluted with incoming air by turbulence.
compressed air supply to the vaporization tubes preheated (100°C) to facilitate complete vaporization of the liquid test material.
- Temperature, humidity, pressure in air chamber: 21 °C, 50 %, pressure not noted
- Air flow rate: 800 l/min
- Air change rate: 11.1



TEST ATMOSPHERE
- Brief description of analytical method used: IR
- Samples taken from breathing zone: yes

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- nominal concentration ( ratio of the amount of test material vaporized to the total amount of air through the chamber) calculated for each chamber for each exposure day.
actual concentration in each chamber measured approximately 1-2 times/h by Miran 1A infrared gas analyzer (wavelength = 13.75 µm).
- analytical equipment standardized daily by vaporizing measured volumes o f the test substance in Saran bags filled with a measured volume (100 L) of air, the concentration of 1,2,3-trichloropropane in each chamber determined by interpolation from a standard curve.

Duration of treatment / exposure:

4 h/d,

Frequency of treatment:

5 d in the first week, 4d in the second week

Remarks:

Doses / Concentrations:
0, 80, 240 or 780 mg/m³ (0, 13, 40 or 132 ppm)
Basis:
nominal conc.

No. of animals per sex per dose:

5

Control animals:

other: yes, but not reported whether sham-exposed or not treated

Details on study design:

- Dose selection rationale: based on a acute study (Gushow) and other data from literature
- Rationale for animal assignment (if not random): random

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: complete check: after each exposure period; check for mortality and water and food supply only: daily on weekends
- complete check: any changes in appearance were noted and recorded


BODY WEIGHT: Yes
- Time schedule for examinations: prior to the 1st , 3rd, 5th and 9th exposures.


FOOD CONSUMPTION: No


FOOD EFFICIENCY: No


WATER CONSUMPTION: No


OPHTHALMOSCOPIC EXAMINATION: No


HAEMATOLOGY: Yes
- Time schedule for collection of blood: after last exposure, collected by orbital sinus puncture immediately prior to sacrifice
- Anaesthetic used for blood collection: Yes, methoxyflurane
- Animals fasted: No
- How many animals: all
- Parameters checked in table 1 were examined.


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: after last exposure, collected at the terminal sacrifice from severed cervical blood vessels of rats and by orbital sinus puncture following light anesthesia with methoxyflurane for mice.
- Animals fasted: No
- How many animals: all
- Parameters checked in table [No.?] were examined.


URINALYSIS: Yes, in rats only
- Time schedule for collection of urine: at the morning prior to the 9th exposure
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters checked: bilirubin , glucose, ketones, occult blood, pH, protein, urobilinogen using chemstrip 7 (Bio-Dynamics/Div. o f BMC, Indianapolis, IN, U.S.A.) and specific gravity (American Optical Co., Keene, NH)


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes: rats were fasted overnight prior to the scheduled sacrifice; mice were not fasted prior to the sacrifice; see table 2

HISTOPATHOLOGY: Yes, see table 2

Statistics:

Descriptive statistics (mean and standard deviation) are reported for white blood cell differential counts and red blood cell indices. Body weights, absolute and relative organ weights, clinical chemistry data, appropriate hematology data and urinary specific gravity were evaluated by Bartlett's test for equality of variances.
Based on the outcome of Bartlett's test , exploratory data analysis was performed by a parametric or non-parametric analysis of variance (ANOVA) , followed respectively by Dunnett's test or Wilcoxon Rank-Sum test w ith a Bonferroni correction for multiple comparisons. Statistical outliers are
identified by a sequential test and excluded a t the discretion of the study di rector.
The nominal alpha levels used and test references are as follows:
Bartlett's test (Winer, 1971) a = 0.01
Parametric ANOVA (Steel and Torrie, 1960) a = 0.10
Non-Parametric ANOVA (Holl ander and
Wolfe, 1973) a = 0.10
Dunnett's test (Winer , 1971) a = 0.05, two-sided
Wilcoxon Rank-Sum test (Hollander and Wolfe, 1973) a = 0.05, two-sided
Bonferroni correction (Miller , 1966)
Outliertest (Grubbs , 1969) a = 0.02, two-sided
Since multiple, interrelated parameters are statistically compared in the same group of animals, the frequency of false positive errors may be much greater than the nominal alpha level. Thus, in addition to statistical analyses, the final toxicologic interpretation of the data also considered factors such as dose-response relationships and whether or not the findings appear to be plausible and consistent in the light of other biologic findings.

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
- Rats and mice in the 780 mg/m³ (132 ppm) group were less active than controls, and did not eat or drink normally after exposure to the test material
o significant effect in the other dose groups


BODY WEIGHT AND WEIGHT GAIN
- The mean body weights of male and female rats in all three exposure groups were decreased in a time and 1,2,3-trichloropropane concentration related manner (Table 3)
- The body weights of male and female mice were not adversely affected by the exposures to 1,2,3-trichloropropane (Table 4)


FOOD CONSUMPTION
not examined

FOOD EFFICIENCY
not examined

WATER CONSUMPTION
not examined

OPHTHALMOSCOPIC EXAMINATION
not examined

HAEMATOLOGY
- The haematology analyses for male and female rats were unremarkable, revealing no 1,2,3-trichloropropane exposure-related changes.
- Likewise for mice, there were no toxicologically significant differences between control and exposure groups, although there were slight but statistically significant increases in the mean platelet counts o f male and female mice i n the high exposure group.
CLINICAL CHEMISTRY
- The concentrations of total serum protein and albumin were significantly increased in male and female rats as well as in male and female mice in the high exposure group. The increases in total serum protein and albumin are of no toxicologic significance.
There were no exposure-related increases in the serum concentrations of marker enzymes (e.g., GOT and GPT = AST and ALT) which are usually
diagnostic of hepatic injury , and the increases in serum protein concentrations were not indicative of organ system damage.
- All other apparent changes in clinical chemistry parameters of rats and mice were considered to be reflections o f the nutritional status of the animals.

URINALYSIS
-The urinalyses revealed a significant decrease in specific gravity of urine in both male and female rats in the high exposure group. Statistically significant decreases in urinary specific gravity also occurred in females in the intermediate and low exposure groups. However, there was no apparent dose-response relationship since the mean specific gravity values for the two groups were nearly identical .
- There were no apparent effects on the other urinary parameters of male or female rats. Neither male nor female rats had evidence of renal toxicity based upon microscopic findings and, therefore, the specific gravity changes were not considered to be an adverse effect .

NEUROBEHAVIOUR
not examined

ORGAN WEIGHTS
Rats:
- There were a variety of differences in organ weights of exposure groups of male and female rats in comparison to controls (Table 5). Most of these differences were reflective of the decreases in body weights a t the time of necropsy. However, the absolute and relative liver weights of male and female rats in the 780 mg/m³ (132 ppm) exposure group were significantly higher than for controls, probably as a result of a direct 1,2,3-trichloropropane effect on the liver. Less pronounced relative liver weight changes also occurred for male and female rats in the intermediate exposure group, possibly reflective of their decreased body weights.
Mice:
- Consistent with the liver weight changes observed for rats , the absolute and relative liver weights of male and female mice in the 780 mg/m³ (132 ppm) group were alsso significantly higher than for control s (Table 6). The liver weights of mice in the intermediate and low exposure groups were not significantly different from controls. The testes weights of male mice in the high exposure group were significantly lower than for controls, but there were no associated histopathologic changes in the testes.

All other organ weight changes in mice were considered to be sporadic occurrences unrelated to exposure to 1,2,3-trichloropropane.

GROSS PATHOLOGY


HISTOPATHOLOGY: NON-NEOPLASTIC
Rats:
- fat:
Consistent with the aforementioned decreases in body weights, there were decreased amounts of abdominal fat in all rats in the intermediate and high exposure groups as well as in one male and one female rat in the low exposure group.
- thymus:
Also, the size of the thymus appeared to be decreased in most 1,2,3-trichloropropane-exposed rats; this observation was considered to be secondary to stress. The microscopic changes in the thymus suggesting some atrophy in the male rats was consistent with the observed decrease in organ weight and gross observations noted at necropsy.
- nasal tissues:
Some effects due to exposure were found i n the nasal tissue of all animals. The degenerative and inflammatory changes were limited to the olfactory epithelial lined portions of the nasal turbinates. The inflammatory process involved the mucosal layer in the olfactory epithelial region, with exudation of inflammatory cells into the lumen of the nasal cavity. In addition to the olfactory mucosal effects observed in the high exposure group, submucosal fibrosis and exostosis were also observed in most of these rats, primarily in the boney structure of the medial septum in the most posterior portion of the nasal turbinates.
- lymphoid tissues:
Likewise, some depletion of splenic lymphoid elements was also observed microscopically in the male rats. The microscopic observations in the lymphoid tissues were interpreted to be secondary and stress-related.
- liver:
The hepatocytes in the 780 mg/m³ (132 ppm) exposure group exhibited slight altered cytoplasmic staining affinity in cells surrounding the central vein. Occasional individual cells were found i n the hepatic lobule which appeared t o be undergoing necrosis. This effect was very minimal, and was not accompanied by a significant increase in serum liver enzymes which are diagnostic of hepatotoxicity.

Mice:
- nasal tissues:
As in rats , the most consistent target organ affected at all levels of exposure was the nasal tissue. The effects in mice nasal tissue were similar to those observed in the rats ; however, no fibrosis was observed in mice, and the effects, in general were less severe in mice than in rats.
- lymphoid tissues:
The 780 mg/m³ (132 ppm) mice had some evidence for stress-related decrease in lymphoid elements in the spleen and mesenteric lymph nodes, comparable to the lymphoid changes noted in rats from this exposure group.
- testes:
There were no histopathologic changes detected in the testes and therefore the previously discussed testicular weight change of male mice in the 780 mg/m³ (132 ppm) group was not considered to be toxicologically significant .
- liver:
The microscopic effects in the liver of male and female mice in the 780 mg/m³ (132 ppm) group were consistent with their increased liver weight. Based upon the microscopic findings, the elevated liver weight was due to vacuolation of the cytoplasm o f the hepatocytes, suggestive of a hydropic change. Due to the vacuolated cytoplasm, these cells also appeared microscopically to be increased in size. The livers of mice stained with PAS did not reveal a difference between control and exposed mice. There were no necrotizing liver effects and no increases in serum enzymes suggestive of hepatotoxicity in these mice.

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
no significant effect in any dose group

Dose descriptor:

LOAEC

Effect level:

80 mg/m³ air (nominal)

Sex:

male/female

Basis for effect level:

other: rat and mouse: adverse effects on the nasal epithelia in both species, more severe with rising dose, no significant effects in haematology, clinical chemistry and urinalysis

Critical effects observed:

not specified

- actual concentrations:

As a result of a calculation error, the mean daily time-weighted average (TWA) exposure concentrations (0, 13, 40 and 132 ppm) were approximately 32% higher than the intended target concentration (0, 10, 30, 100 ppm) for each exposure chamber. The mean daily nominal concentrations were in reasonable agreement with the mean daily TWA analytical concentrations. However, the nominal concentrations were approximately 10%, 7% and 23% higher than the TWA analytical concentrations for the high, intermediate, and low exposure chambers, respectively. The reason for the greater difference between nominal and analytical concentrations in the low exposure chamber is unknown.

- Table 3: body weights of rats

Days of Exposure	Sex	Exposure Concentration (ppm)
		0	13	40	132
1	Male	144.6	146.2	149.3	147.4
SD		4.8	2.8	4.6	8.5
No. of animals		5	5	5	5
3		154.7	149.1	147.3	138.3*
SD		4.2	2.7	5.2	7.4
No. of animals		5	5	5	5
5		163.0	156.1	154.4*	140.6*
SD		4.5	2.6	5.8	5.7
No. of animals		5	5	5	5
11		184.1	172.6*	169.1*	158.3*
SD		2.3	4.8	6.5	8.5
No. of animals		5	5	5	5
1	Female	127.9	127.2	127.7	126.8
SD		3.1	3.5	3.1	2.1
No. of animals		5	5	5	5
3		129.5	126.2	120.4*	115.2*
SD		4.1	2.5	3.7	3.2
No. of animals		5	5	5	5
5		130.1	128.5	123.9*	114.2*
SD		4.0	2.4	3.5	3.6
No. of animals		5	5	5	5
11		139.6	130.8*	128.5*	125.0*
SD		3.6	3.3	4.3	4.5
No. of animals		5	5	5	5

*Indicates significant difference from control by Dunnett's test, alpha = 0.05, two-sided.

- Table 4: bw mice

Days of Exposure	Sex	Exposure Concentration (ppm)
		0	13	40	132
1	Male	18.7	19.0	18.8	19.7
SD		1.2	2.2	0.9	1.3
No. of animals		5	5	5	5
3		18.5	18.5	18.7	17.8
SD		1.0	1.3	0.8	1.5
No. of animals		5	5	5	5
5		18.7	18.8	19.3	18.1
SD		1.3	1.4	1.5	1.1
No. of animals		5	5	5	5
11		19.5	20.1	20.7	21.1
SD		1.9	1.4	1.0	1.8
No. of animals		5	5	5	5
1	Female	16.5	16.1	16.3	16.1
SD		1.0	0.8	1.1	1.0
No. of animals		5	5	5	5
3		16.0	16.5	16.0	14.8
SD		1.7	0.8	1.0	1.0
No. of animals		5	5	5	5
5		15.9	17.0	16.0	15.1
SD		2.3	1.2	1.3	1.7
No. of animals		5	5	5	5
11		17.2	17.8	17.2	19.2
SD		1.3	1.3	1.4	1.7
No. of animals		5	5	5	5

No statistically significant differences from control group means by Dunnett's or Wilcoxon's tests, alpha = 0.05, two-sided.

- Table 5: exposure concentrations and chamber conditions

Target Conc. (ppm)	Analytical Concentration			Nominal	Concentration	Temp.       (^°C)^c		Rel. Hum.  (%)^c
	Analytical Conc.	Coeff of Var. b	Range of Values	Mean*SD	Range of Values
						Max.           Min.
0						23	24	39±5
10	13±0.5	4%	12-14	16±0.6	15-17	22	24	43±3
30	40±0.4	1%	39-40	43±0.9	41-44	23	24	46±3
100	132±0.6	0.5%	131-133	145± 2	141-149	23	25	44±2

^aNumbers are X ± SD daily time-weighted average (TWA) values for 9 exposures.

^bCoefficient of variation is the standard deviation of daily TWA measurements divided by the mean value (X100).

^cX ± SD of daily measurements for 9 exposure days.

- None detected.

Conclusions:

1,2,3-Trichloropropane was tested in a 14 d repeated dose inhalation study (exposure: 5d/ wk, 4 h/d) following generally TG OECD 412. Clinical chemistry and haemotological examinations were not conducted. Clinical chemistry effects were shown to be absent even at higher concentrations in accompanying study (Miller 1986 A). Histopathological changes in the nasal tissues of rats and mice were found leading to NOAECs of 6 mg/m³ (1 ppm) for the rat and 18 mg/m³ (3 ppm ) for the mouse.

Executive summary:

The present study DOW HET-K-002524-004 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity, higher doses) was conducted to asses the toxic effects of 1,2,3 -Trichloropropane for rats and mice after repeated inhalation exposure (4 h/d, 9 exposures in 14 d, concentrations: 0, 80, 240 or 780 mg/m³ (0, 13, 40 or 132 ppm)). No NOAECs were found, as histologic effects were found in the nasal tissues of rats and mice of all dose groups. In addition in rats body weight effects were observed in all dose groups.

Male and female Fischer 344 rats and B6C3F1 mice were analyzed daily for clinical signs, expect on weekends. Body weights were measured prior to the 1st, 3rd, 5th and 9th exposures. In rats urinalysis was conducted at the morning prior to the 9th exposure. Blood samples for clinical chemistry and haematology were taken after the last exposure. At the end of the study the animals were sacrificed and subjected to gross necroscopy and histological analysis of various tissues.

The primary effect of exposure in rats and mice was a microscopic degenerative and inflammatory change in the nasal olfactory mucosa. The effects were observed at all exposure levels in both species and they were concentration dependent in severity.

Male and female rats in all exposure groups gained less body weight than controls, while the body weights of mice were unaffected by the TCP exposures. Statistically significant increases in the liver weights of male and female rats and mice in the 780 mg/m³ (780 mg/m³ (132 ppm)) group were also identified.

However, there were no microscopic changes in the liver indicative of severe hepatoxicity, nor any changes in serum enzymes which were diagnostic of liver injury. In mice in the 780 mg/m³ (780 mg/m³ (132 ppm)) group, the microscopic observations indicated that the increase in liver weight was due to increased glycogen deposition, possibly resulting from a slight change in the feeding habits of the high exposure group. Since mice were not fasted prior to necropsy as are the rats, the presence of glycogen is more readily observed microscopically in the mice.

The various changes in lymphoid tissues observed in 1,2,3 -trichloropropane-exposed animals are frequently seen in stressed animals and were considered to be secondary effects.

The specific gravity of urine of male and female rats in the 780 mg/m³ (132 ppm) group was significantly lower than for controls, but the blood urea nitrogen values for those animals were not elevated and there were no gross or histopathologic changes in kidneys of either rats or mice. Hence, the decreases in urinary specific gravity were not considered to be toxicologically significant.

In conclusion, degenerative and inflammatory changes in the olfactory nasal mucosa were the primary effects in rats and mice exposed to 1,2,3 -trichloropropane vapors. Since a no-adverse-effect level was not achieved with regard to the nasal mucosa, a follow-up study was initiated to define a no-adverse-effect level using target concentrations of 0, 1, 3 or 10 ppm DOW HET-K-002524-006 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity, lower doses).

 

Reference 2

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26/08/1985 - 13/05/1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: - scientifically sound study - generally guideline compliant - missing urinalysis, clinical chemistry and haematology are covered by respective experiments in DOW HET-K-002524-004 with the same animal strains

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)

Deviations:

yes

Remarks:

: no haematology examinations, only limited biochemical and urinalysis examinations

GLP compliance:

yes

Limit test:

no

Species:

other: rat and mouse

Strain:

other: Fischer 344 rats and B6C3F1 mice

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc. (Kingston, NY and Portage, MI, U.S.A. )
- Age at study initiation: 6-8 wk
- Weight at study initiation: rats: 211.1 g (male), 140.1 g (female); mice: 24.6 g (male), 23.3 g (female)
- Fasting period before study: not reported
- Housing: housed singly in stainless steel cages with wire bottoms
- Diet (e.g. ad libitum): Purina Certified Rodent Chow (Ralston Purina Co., St . Louis, MO), ad libitum
- Water (e.g. ad libitum): tap water, analyzed periodically by the City o f Midland, MI
- Acclimation period: 7 d


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.2
- Humidity (%): 50
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: not precisely reported

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: not applicable

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: 4.1 m³ stainless steel and glass chambers
- Method of holding animals in test chamber: Exposures were conducted i n the
same cages used for housing the animals.
- Source and rate of air: 800 L/min;
- Method of conditioning air: air supplied to the chambers controlled by a system designed to maintain temperature at approximately 21°C and relative humidity at approximately 50%; temperature and relative humidity recorded at the end of each exposure period.
- System of generating vapour:
metering the liquid test material at controlled rates into vaporization tubes as described by Miller et. al. (Miller , R. R., Letts, R. L.. Potts, W. J. and McKenna, M. J. (1980) Improved methodology for generating controlled test atmospheres. Am. Ind. Hyg. Assoc. J. 41:844-846.).
Vapors swept into the exposurechamber inlet ducts with compressed air and mixed and diluted with incoming air by turbulence.
compressed air supply to the vaporization tubes preheated (100°C) to facilitate complete vaporization of the liquid test material.
- Temperature, humidity, pressure in air chamber: 21 °C, 50 %, pressure not noted
- Air flow rate: 800 l/min
- Air change rate: 11.1

TEST ATMOSPHERE
- Brief description of analytical method used: GC-FID
- Samples taken from breathing zone: yes

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The actual concentration in each chamber was measured approximately 1-2 times/hr by gas chromatography (peak height) using a Varian Model 1400 gas chromatograph with flame ionization detector using a 6'x1/8" stainless-steel column (142°C) packed with 8% Triton X-305 on 100/120 CW-HP.
The analytical equipment was standardized daily by vaporizing measured volumes o f the test substance i n Saran bags filled with a measured volume (100 L) of air. The concentration o f TCP in each chamber was then determined by interpolation from a standard curve.

Duration of treatment / exposure:

4 h/d,

Frequency of treatment:

5 d in the first week, 4d in the second week

Remarks:

Doses / Concentrations:
0, 6, 18 or 60 mg/m³ (0, 1, 3 or 10 ppm)
Basis:
nominal conc.

No. of animals per sex per dose:

5

Control animals:

other: yes, but not reported whether sham-exposed or not treated

Details on study design:

- Dose selection rationale: based on study Miller (1986 A) where 0.08 mg/L air (13 ppm) was a LOAEL
- Rationale for animal assignment (if not random): random

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: complete check: after each exposure period; check for mortality and water and food supply only: daily on weekends
- complete check: any changes in appearance were noted and recorded



BODY WEIGHT: Yes
- Time schedule for examinations: prior to the 1st , 3rd, 5th and 9th exposures.


FOOD CONSUMPTION: No


FOOD EFFICIENCY: No


WATER CONSUMPTION: No


OPHTHALMOSCOPIC EXAMINATION: No


HAEMATOLOGY: No


CLINICAL CHEMISTRY: No, as no significant findings were reported for higher concentrations in a preceding study with the same animal strains and the same study design


URINALYSIS: Yes, in rats only
- Time schedule for collection of urine: at the morning prior to the 9th exposure
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters checked: bilirubin , glucose, ketones, occult blood, pH, protein, urobilinogen using chemstrip 7 (Bio-Dynamics/Div. o f BMC, Indianapolis, IN, U.S.A.) and specific gravity (American Optical Co., Keene, NH)


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes: rats were fasted overnight prior to the scheduled sacrifice; mice were not fasted prior to the sacrifice
Weights recorded of brain, heart, liver , kidneys, thymus (rats)
HISTOPATHOLOGY: Yes: tested tissues:
liver
pancreas
peripheral nerve
adrenals
small intestine
mesenteric lymph node
epididymides
prostate
oviducts
urinary bladder
salivary glands
mediastinal lymph node
thyroid gland
larynx
eyes
lacrimal/harderian glands
oral tissues
heart
brain
spinal cord
kidneys
cecum
mesenteric tissues
seminal vesicles
uterus
cervix
lungs
thymus
aorta
parathyroid glands
skin
tongue
auditory sebac gland
gall bladder (mice only)
spleen
pituitary
bone marrow
stomach
large intestine
testes
coaguiating glands
ovaries
vagina
skeletal muscle
mediastinal tissues
esophagus
trachea
mammary gland
nasal tissues
bone

Statistics:

Body weights, absolute and relative organ weights and urinary specific gravity were evaluated by Bartlett's test for equality of variances. Based on the outcome of Bartlett's test, exploratory data analysis was performed by a parametric or non-parametric analysis of variance (ANOVA), followed respectively by Dunnett's test or Wilcoxon Rank-Sum test with a Bonferroni correction for multiple comparisons.
Statistical outliers were identified by a sequential test and excluded at the discretion of the study director.
The nominal alpha levels to be used and test references were as follows:
Bartlett's test (Winer, 1971) a = 0.01
Parametric ANOVA (Steel and Torrie, 1960) u = 0.10
Non-Parametri c ANOVA (Holl ander and
Wolfe, 1973) a = 0.10
Dunnett's test (Winer, 1971) a = 0.05, two-sided
Wilcoxon Rank-Sum test (Hollander and
Wolfe, 1973) a = 0.05, two-sided
Bonferroni correction (Miller, 1966)
Outlier test (Grubbs, 1969) a = 0.02, two-sided
Since multiple, interrelated parameters were statistically compared in the same group of animals, the frequency of false positive errors may have been much greater than the nominal alpha level. Thus, in addition to statistical analyses, the final toxicologic interpretation of the data includes factors such as dose-response relationships and whether or not the findings appear to be plausible and consistent in the light of other biologic findings.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
no significant effect in any dose group
not examined

BODY WEIGHT AND WEIGHT GAIN
no significant effect in any dose group

FOOD CONSUMPTION
not examined

FOOD EFFICIENCY
not examined

WATER CONSUMPTION
not examined

OPHTHALMOSCOPIC EXAMINATION
not examined

HAEMATOLOGY
not examined

CLINICAL CHEMISTRY
not examined

URINALYSIS
no significant effect in any dose group

NEUROBEHAVIOUR
not examined

ORGAN WEIGHTS
no significant effect in any dose group

GROSS PATHOLOGY
no significant effect in any dose group

HISTOPATHOLOGY: NON-NEOPLASTIC
rats: - very slight exposure related degenerative changes and inflammation in the olfactory epithelium of male and female rats in the 60 mg/m³ (10 ppm) group, and the thickness o f the olfactory epithelium was very slightly decreased in male and female rats in the 18 mg/m³ (3 ppm) group
- no effects on nasal tissues in the 6 mg/m³ (1 ppm) group
mice: - inflammatory reaction in the olfactory epithelial region of 60 mg/m³ (10 ppm) exposed mice, confined to the mucosa and associated with the focal change in thickness
- no effects on nasal tissues in the 16 mg/m³ (3 ppm) group

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
no significant effect in any dose group

Dose descriptor:

NOAEC

Effect level:

6 mg/m³ air (nominal)

Sex:

male/female

Basis for effect level:

other: rat: based on the absence of any adverse effects, especially absence of effects on nasal tissues

Dose descriptor:

NOAEC

Effect level:

18 mg/m³ air (nominal)

Sex:

male/female

Basis for effect level:

other: mouse: based on the absence of any adverse effects, especially absence of effects on nasal tissues

Dose descriptor:

LOAEC

Effect level:

18 mg/m³ air (nominal)

Sex:

male/female

Basis for effect level:

other: rat: thickness o f the olfactory epithelium was very slightly decreased in both sexes, degenerative changes and inflammation in this tissue at higher concentrations

Dose descriptor:

LOAEC

Effect level:

60 mg/m³ air (nominal)

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

not specified

- table 1: exposure concentrations and chamber conditions

Target Conc. (ppm)	Analytical concentration			Nominal Concentration		Temp. (°C) (c)
	Analytical concentration (a)	Coefficient of variation (b)	Rangeof	Mean ± SD	Rangeof	Max.	Min.	Rel. Hum. (%) (c)
0			-			21.1	19.6	64.7
1	1.0±0.0	0%	0	0.9±0.1	0.8- 1.0	20.2	21.4	66.3
3	2.9±0.2	7%	2.5-3.2	2.6±0.2	2.3- 2.7	20.0	21.0	68.6
10	9.7±0..3 (d)	3%	9.2-10.0	12.1±0.9	11.0-13.2	20.6	21.6	69.3

(a) Numbers are X ± SD daily time-weighted average (TWA) values for 9 exposures.

(b) Coefficient of variation is the SD of the daily TWA measurements divided by X (X100).

(c) X ± SD of daily measurements for 9 exposure days.

(d) On day 8, the 10 ppm exposures were conducted for. only 4.5 hours instead of 6 hours as a result of an operational error.

- None

Conclusions:

1,2,3-Trichloropropane was tested in a 14 d repeated dose inhalation study (exposure: 5d/ wk, 4 h/d) following generally TG OECD 412. Clinical chemistry and haemotological examinations were not conducted no effects were found even at higher concentrations in an accompanying study (Miller 1986 A). Histopathological changes in the nasal tissues of rats and mice were found leading to NOAECs of 6 mg/m³ (1 ppm) for the rat and 18 mg/m³ (3 ppm ) for the mouse.

Executive summary:

The present study DOW HET-K-002524-006 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity lower doses) was a follow up study to DOW HET-K-002524-004 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity, higher doses) and conducted to asses the NOAEC for 1,2,3 -Trichloropropane for rats and mice after repeated inhalation exposure (4 h/d, 9 exposures in 14 d, concentrations: 0, 6, 18 or 60 mg/m³ (0, 1, 3 or 10 ppm)). NOAECs of 6 mg/m³ (1 ppm) for the rat and 18 mg/m³ (3 ppm ) for the mouse were found, the corresponding LOAECs are 18 mg/m³ (3 ppm) for the rat and 60 mg/m³ (10 ppm) for the mouse.

Male and female Fischer 344 rats and B6C3F1 mice were analyzed daily for clinical signs, expect on weekends. Body weights were measured prior to the 1st , 3rd, 5th and 9th exposures. In rats urinalysis was conducted at the morning prior to the 9th exposure. At the end of the study the animals were sacrificed and subjected to gross necroscopy and histological analysis of various tissues.

Body weights, organ weights and urinalyses were unaffected by the TCP exposures. Histopathologic examinations of the nasal tissues revealed very slight exposure-related changes in the olfactory epithelium of rats in the 3 ppm and 10 ppm groups, as well as in mice in the 10 ppm group. Similar effects on the olfactory epithelium had previously been found in rats and mice exposed to 13 ppm TCP vapors in a previous study; more pronounced effects on nasal tissues occurred in animals exposed t o 40 or 132 ppm (DOW HET-K-002524-004 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity, higher doses)).

Reference 3

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: - pre OECD, but generally compliant to OECD TG 413 as at 1981 - GLP compliant - study only available as summary from the SIDS report

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 413 (Subchronic Inhalation Toxicity: 90-Day Study)

GLP compliance:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, NY, U.S.A.
- Age at study initiation: 51 d
- Weight at study initiation: not reported in SIDS report summary
- Fasting period before study: no
- Housing: doubly housed
- Diet (e.g. ad libitum): Purina Rodent Chow 5001; Purina Co., St. Louis, Mo., U.S.A.
- Water (e.g. ad libitum): ad libitum, except for the exposure periods, when water was withheld from the animals
- Acclimation period: >= 12 d


ENVIRONMENTAL CONDITIONS
- not reported in SIDS report study summary or Johannsen 1988

Route of administration:

inhalation: vapour

Type of inhalation exposure:

not specified

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: not applicable

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: stainless steel and glass exposure chambers, volume: 10 m³
- Source of air: filtered outside air
- Method of holding animals in test chamber: not reported in SIDS report study summary or in Johannsen 1988
- System of generating vapour: Vapor was generated by placing the test material into a bubbler through which nitrogen was metered. The resultant vapor passed through an in-line trap into the supply air portal. Adjusting the flow of nitrogen through the bubbler controlled the amount of material vaporized.
- Temperature, humidity, pressure in air chamber: not reported in SIDS report summary or in Johannsen 1988
- Air flow rate: 3 m³/min
- Air change rate: 18/h


TEST ATMOSPHERE
- Brief description of analytical method used: gas chromatography and electron capture detection
- Samples taken from breathing zone: not reported in SIDS report summary or in Johannsen 1988

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

1,2,3-trichloropropane, was drawn through the impinger at accelerated flow rates of 1.0 L/min for 10 min and 10 L/min for 5 min for the 0.5 and 1.5 ppm chambers, respectively. Aliquots of the acetone solution were analyzed by gas chromatography and electron capture detection. Actual chamber calculations were determined.
- The amount of test material delivered was determined by weighing the test material container before and after each exposure. This, divided by the total volume of air, yielded the nominal exposure concentration.

Duration of treatment / exposure:

13 wks, 5 d/wk, 6 h/d (=65 exposures)

Frequency of treatment:

5 d/wk

Remarks:

Doses / Concentrations:
0, 0.5, 1.5 ppm (= 0, 3.0, 9 mg/m³)
Basis:
nominal conc.

Remarks:

Doses / Concentrations:
0, 0.5 ± 0.01, 1.54 ± 0.02 ppm
Basis:
analytical conc.

No. of animals per sex per dose:

15

Control animals:

yes

Details on study design:

- Dose selection rationale: The dose setting was based on the results of a 4 wk range finding study (Johannsen 1988)
- no further details reported in SIDS report study summary or in Johannsen 1988

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- checked for signs of toxicity, morbidity, and mortality.


DETAILED CLINICAL OBSERVATIONS: Yes, full physical assessment
- Time schedule: weekly


BODY WEIGHT: Yes
- Time schedule for examinations: Determined individually from 2 weeks prior to exposure through termination, including the first day of exposure (Day 0).


FOOD CONSUMPTION:
- No


FOOD EFFICIENCY:
- No


WATER CONSUMPTION: No


OPHTHALMOSCOPIC EXAMINATION: No


HAEMATOLOGY: Yes
- Time schedule for collection of blood: Determined at weeks 7 and 13 in 10/sex/group
- Anaesthetic used for blood collection: No data
- Animals fasted: Yes, over night
- How many animals: 10/sex/dose
- Parameters checked in table 1 were examined.


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Determined at weeks 7 and 13 in 10/sex/group
- Animals fasted: Yes, over night
- How many animals: 10/sex/dose
- Parameters checked in table 1 were examined.


URINALYSIS: No


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, Full compliment of tissues were fixed and examined, organweights determined (see table 2)
HISTOPATHOLOGY: Yes, (see table 2)

Other examinations:

no

Statistics:

Body weight, hematology, clinical chemistry, organ weight, organ/body weight, and organ/brain weight values were statistically evaluated using the F-test and Student's F-test (Snedecor, G. S. and W. G. Cochran, Statistical Methods. 1967) or Dunnett's test (1955 and 1964).

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY
Animals of both sexes in the treatment groups displayed increased incidence of lacrimation throughout the test. There were no compound-related deaths.

BODY WEIGHT AND WEIGHT GAIN
There were no compound-related effects on body weight gain.

FOOD CONSUMPTION
not examined

FOOD EFFICIENCY
not examined

WATER CONSUMPTION
not examined

OPHTHALMOSCOPIC EXAMINATION
not examined

HAEMATOLOGY
Statistically increased erythrocyte counts, accompanied by increased hemoglobin (low-dose), in males in both dose groups at week 7 was not confirmed at week 13 and therefore was not deemed toxicologically relevant. There were no other significant findings.

CLINICAL CHEMISTRY
Decreases in bilirubin (direct and total) and lactic dehydrogenase values in dosed males at both time intervals were sporadic, not significant in a dose-related manner and were not considered toxicologically relevant. Fasting glucose values were increased in high-dose males and females, but were significant in females only.

URINALYSIS
not examined

NEUROBEHAVIOUR
not examined

ORGAN WEIGHTS
Increases in mean and absolute lung weights in treated males were significant at the high dose only. However, these weight changes occurred with decreased mean terminal body weights for these males. Increased mean absolute and relative ovarian weights in mid- and high-dose females were significant in high-dose females only. There were no other organ weights changes related to treatment.

GROSS PATHOLOGY
There were no significant changes associated with treatment.

HISTOPATHOLOGY: NON-NEOPLASTIC
not examined

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
There were no significant changes associated with
treatment.

Dose descriptor:

NOAEC

Effect level:

1.5 ppm

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

not specified

Conclusions:

The toxicity of 1,2,3-trichloropropane towards Sprague-Dawley rats was tested in a repeated dose inhalation bioassay (13 wks, 6 h 5 d/week; 0, 0.5, 1.5). Altered fasted glucose levels and ovarian weight effects were found in high dose females, increased absolute and relative lung weights in high dose males. As no adverse effects were reported concerning the histopathology of these tissues the highest dose = 1.5 ppm was reported as the NOAEC by the SIDS report on TCP.

Executive summary:

In the present study (Monsanto 1983) Sprague-Dawley rats were exposed to vapors of 1,2,3 -trichloropropane for 13 wks (5 d/wk, 6 h/d,; 0, 0.5, 1.5 ppm = 0, 3.0, 9.0 mg/m³) following generally OECD TG 413.

Based on the derived results the highdose = 1.5 ppm (= 9 mg/m³) is reported as NOAEC by the SIDS report of 2004 on 1,2,3 -trichloropropane.

The animals were checked twice daily for viability and appearance, and a physical assessment and bodyweight determination were carried out weekly. Blood samples for haematology and clinical chemistry and urine samples were taken after week 7 and at study termination in all groups (animals fastened over night prior to blood withdrawl). After final sacrifice animals were subjected to gross necroscopy, Absolute and relative organ weights (organ-body wt) were measured and a full compliment of tissues were fixed and examined histologically.

No mortality was reported in any dose group. As clinical signs increased incidence of lacrimation throughout the test in all treated animals was reported. No adverse effects on body weights were detected in any dose group. Aberrations in erythrocyte counts were only seen at the interim blood withdrawl and therefore not regarded at adverse. While decreased bilirubin values were sporadic and not treatment related, fasting glucose values were raised significantly in females of the high dose group. Mean and absolute lung weights were increased significantly in treated males of the high dose group that showed decreased mean terminal body weights. Mean absolute and relative ovarian weights were raised in mid- and high-dose females reaching statistical significance in high-dose animals. But as there was no such dose dependent effect in the study by Rusch (1979) at higher doses in the same animal strain under comparable exposure conditions, these findings are regarded as not substance related. There were no other organ weights changes related to treatment.

No adverse effects are reported for gross necroscopy or histopathological analysis.

Reference 4

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: - pre OECD, but generally compliant to OECD TG 413 - GLP compliant - histology incomplete, no NOAEC determinable (according to the SIDS report summary) - study only available as summary from the SIDS report and as summary from Johannsen et al 1988

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 413 (Subchronic Inhalation Toxicity: 90-Day Study)

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Wilmington, MA, U.S.A.
- Age at study initiation: 7 wks
- Weight at study initiation: not reported in SIDS report summary or Johannsen 1988
- Fasting period before study: no
- Housing: not reported in SIDS report summary or Johannsen 1988
- Diet (e.g. ad libitum): Purina Rodent Chow 5001; Purina Co., St. Louis, Mo., U.S.A.
- Water (e.g. ad libitum): ad libitum, except for the exposure periods, when water was withheld from the animals
- Acclimation period: >= 12 d


ENVIRONMENTAL CONDITIONS
- Temperature (°C): not reported in SIDS report summary or Johannsen 1988
- Humidity (%): not reported in SIDS report summary or Johannsen 1988
- Air changes (per hr): not reported in SIDS report summary or Johannsen 1988
- Photoperiod (hrs dark / hrs light): not reported in SIDS report summary or Johannsen 1988

Route of administration:

inhalation: vapour

Type of inhalation exposure:

not specified

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: not applicable

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: stainless steel and glass exposure chambers, total volume of one cubic meter with an effective volume of 760 liters.
- Method of holding animals in test chamber: not reported in SIDS report summary or Johannsen 1988
- Source and rate of air: source not reported in SIDS report summary or Johannsen 1988
- Method of conditioning air: not reported in the SIDS report summary
- System of generating vapour: Vapor was generated by bubbling dry air through the test material in gas washing bottles. Adjusting the flow of air through the gas-washing bottle controlled the amount of material vaporized. The resulting vapor was then fed into a port on the chamber air intake line and diluted to the exposure concentration with room air.
- Temperature, humidity, pressure in air chamber:
- Air flow rate: conflicting information: 130 L/min according to SIDS report study summary , 144 l/min according to Johannsen 1988
- Air change rate: 7.8 air changes/h (SIDS) or 5.3 (Johannsen)
- Treatment of exhaust air: not reported in the SIDS report study summary or Johannsen 1988
- Source and rate of air: not reported in the SIDS report study summary or Johannsen 1988

TEST ATMOSPHERE
- Brief description of analytical method used: IR measurement
- Samples taken from breathing zone: no data

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

- chamber air concentrations measured at least 3 times/day chamber using a Miran model II A infrared analyzer (Wilks Instrument Co., Darien, Conn.) by comparison of absorption to calibration curves (wavelength = 10.9 µm; pathlength = 8.55).

Duration of treatment / exposure:

6 h /day, 5 d/wk for 13 wks

Frequency of treatment:

5 d/wk

Remarks:

Doses / Concentrations:
0, 5, 15 and 50 ppm (0, 30, 90 and 300 mg/m³).
Basis:
no data

Remarks:

Doses / Concentrations:
0, 4.5 ± 0.2, 15.0 ± 0.3, 49.0 ± 1.0 ppm
Basis:
analytical conc.

No. of animals per sex per dose:

15 rats per sex and dose, probably 15 additional animals in controls and high dose groups as hematology was performed for these groups after 7 weeks and after 13 weeks with 15 respectively (unclear from the SIDS report summary)

Control animals:

yes

Details on study design:

- Dose selection rationale: Based on the results of a 4 wk range finding study
- no further details reported in SIDS report study summary or in Johannsen 1988

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily


DETAILED CLINICAL OBSERVATIONS: Yes, full physical assessment
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: Determined individually from 2 weeks prior to exposure through termination, including the first day of exposure (Day 0).

FOOD CONSUMPTION:
Not stated in the original report


FOOD EFFICIENCY:
Not stated in the original report


WATER CONSUMPTION:
Not reported in the SIDS report summary


OPHTHALMOSCOPIC EXAMINATION:
Not reported in the SIDS report summary

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Determined at week 7 in 15/sex/control and high-dose groups; and at week 13 in 15/sex/group (all groups).
- Anaesthetic used for blood collection: No data
- Animals fasted: after week 7: no; after week 13: yes
- How many animals: 15 per dose group
- Parameter examined: hemoglobin, hematocrit, erythrocyte count, clotting time, and total and differential leukocytes.


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Determined at week 7 in 15/sex/control and high-dose groups; and at week 13 in 15/sex/group (all groups).
- Anaesthetic used for blood collection: No data
- Animals fasted: after week 7: no; after week 13: yes
- How many animals: 15 per dose group
- Parameters examined: serum glutamic pyruvic transaminase (ALT), alkaline phosphatase, BUN, and glucose.

URINALYSIS: Yes
- Time schedule for collection of urine: Determined at week 7 in 15/sex/control and high-dose groups; and at week 13 in 15/sex/group (all groups).
- Anaesthetic used for blood collection: No data
- Animals fasted: after week 7: no; after week 13: yes
- How many animals: 15 per dose group
- Parameters examined: appearance, specific gravity, pH, protein, bilirubin, ketones, glucose, occult blood, and microscopic examination of urinary sediment.


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes: Full compliment of tissues were fixed and examined. Absolute and relative organ weights (organ-body wt) were measured.
HISTOPATHOLOGY: Yes: High-dose and control animals only were selected for histopathological exam from a full compliment of tissues.

Other examinations:

no data

Statistics:

Body weight, hematology, clinical chemistry, organ weight, organ/body weight, and organ/brain weight values were statistically evaluated using the F-test and Student's F-test (Snedecor, G. S. and W. G. Cochran, Statistical Methods. 1967) or Dunnett's test (1955 and 1964).

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY
- Red nasal discharge and moist rales were more frequently observed in mid- and high- dose animals; also, excessive lacrimation and yellow staining of the anogenital fur were considered treatment related.
- No mortality was reported

BODY WEIGHT AND WEIGHT GAIN
- Mean body weight values for 1,2,3-trichloropropane test group females in the mid- and high-doses were significantly depressed (compared to controls) beginning at weeks 7 and 2, respectively.

FOOD CONSUMPTION
- not analysed

FOOD EFFICIENCY
- not analysed

WATER CONSUMPTION
- not analysed

OPHTHALMOSCOPIC EXAMINATION
- not analysed

HAEMATOLOGY
- The only differences noted were increased leukocyte values in mid- (week 13) and high-dose (week 7/13) males/females. All other values were unremarkable or sporadic and unrelated to dose. Week 7 values were non-fasted; week 13 values were fasted.

CLINICAL CHEMISTRY
- The only significant difference noted was increased serum glutamic pyruvic transaminase values in mid- (week 13) and high-dose (week 7/13) females. All other values were unremarkable or sporadic and unrelated to dose. Week 7 values were non-fasted; week 13 values were fasted.

URINALYSIS
- There were no compound-related differences observed.

NEUROBEHAVIOUR
- not analysed

ORGAN WEIGHTS
Statistically significant increases in absolute and relative liver weights of males (all dosed groups) and females (mid- and high-doses). The mean liver/brain weight ratios were significantly elevated in all dosed males and in high-dose females. Ovarian weights were significantly reduced in in the 15 ppm group, but not in the 50 ppm group. Therefore this is regarded not treatment related

GROSS PATHOLOGY
There were no obvious compound related effects observed.

HISTOPATHOLOGY: NON-NEOPLASTIC
High-dose and control animals only were selected for histopathological exam from a full compliment of tissues. Microscopic examination revealed treatment related findings in the liver and lungs of the high-dose males and lungs and spleen of high-dose females. Therefore this tissues were analysed in all animals of all dose groups:
lungs: peribronchial lymphoid hyperplasia
5 ppm: mild, 6/15 males, 5/15 females
15 ppm: mild to marked in males, less severe in females, 11/15 males, 4/15 females
50 ppm: mild to marked, 10/15 males, 6/15 females
liver: mild centrilobular to midzonal hepatocellular hypertrophy, males only
5 ppm: 13/15
15 ppm: 15/15
50 ppm: 15/15
spleen: mild to marked extramedullary hematopoiesis (severity dose dependent), in females only
0 ppm (control): 5/15
5 ppm: 7/15
15 ppm: 9/15
50 ppm: 13/15

Dose descriptor:

NOAEC

Remarks on result:

not determinable

Remarks:

no NOAEC identified

Dose descriptor:

LOAEC

Effect level:

5 ppm

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

not specified

Conclusions:

The toxicity of 1,2,3-trichloropropane towards Sprague-Dawley rats was tested in a repeated dose inhalaton bioassay (13 wks, 6 h 5 d/week; 0, 5, 15, 50 ppm). Liver weight effects were found in males in all dose-groups. Due to the lack of histology data for the mid- and the high-dose groups it cannot be decided whether these effects are to be regarded adverse at both dose levels. Therefore a derivation of a NOAEC is not possible.

Executive summary:

In the present study (Rusch 1979) Sprague-Dawley rats were exposed to vapors of 1,2,3 -trichloropropane for 13 wks (5 d/wk, 6 h/d,; 0, 5, 15, 50 ppm = 0, 30, 90 and 300 mg/m³) following generally OECD TG 413.

Based on the derived results the determination of a NOAEC or a LOAEC is not possible due to the lack of histology data for the mid- and the high-dose group.

The animals were checked twice daily for viability and appearance, and a physical assessment and bodyweight determination were carried out weekly. Blood samples for haematology and clinical chemistry and urine samples were taken after week 7 in the control and the high dose groups and at study termination in all groups. Week 7 values were non-fasted; week 13 values were fasted. After final sacrifice animals were subjected to gross necroscopy, Absolute and relative organ weights (organ-body wt) were measured and a full compliment of tissues were fixed and examined histologically.

No mortality was reported in any dose group. As clinical signs red nasal discharge and moist rales were more frequently observed in mid- and high- dose animals and excessive lacrimation and yellow staining of the anogenital fur were considered treatment related. Mean body weight values for 1,2,3-trichloropropane test group females in the mid- and high-doses were significantly depressed (compared to controls) beginning at weeks 7 and 2, respectively. In haematological examinations the only differences noted were increased leukocyte values in mid- (week 13) and high-dose (week 7/13) males/females. All other values were unremarkable or sporadic and unrelated to dose. The only significant difference in clinical chemical parameters noted was increased serum glutamic pyruvic transaminase values in mid- (week 13) and high-dose (week 7/13) females. All other values were unremarkable or sporadic and unrelated to dose. No compound-related effects were found in urinalysis in any of the dose groups. Regarding organ weights statistically significant increases in absolute and relative liver weights of males (all dosed groups) and females (mid- and high-doses) were reported. The mean liver/brain weight ratios were significantly elevated in all dosed males and in high-dose females. Other changes were not considered biologically significant. Histopathological examinations revealed treatment related findings in the liver and lungs of all treated males and lungs and spleen of all treated females. They consisted of mild centrilobular to midzonal hepatocellular hypertrophy (liver), mild to marked peribronchial lymphoid hyperplasia (lung), and mild to marked extramedullary hematopoiesis and the severity of all this effects was raised dose dependently. Upon gross necroscopy no coumpound related effects were noted.

Due to the lack of histology data for the mid- and the high-dose groups it cannot be decided whether the organ weight effects are to be regarded adverse at these dose levels. Therefore a derivation of a NOAEC is not possible.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEC

6 mg/m³

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

- Repeated dose toxicity, oral: The LOAEL(rat subchronic) of 8 mg/Kg bw/day is based on the findings in Hazleton (1983) / key (120d study on F344 rats) where increased liver weights were found down to 8 mg/kg/day in males, which is the lowest concentration tested, and at 16 mg/kg/d in females. Liver and kidneys were identified as main target organs reflected by multifocal necrosis, necrosis of individual hepatocytes, the presence of sinusoidal pigment and bile duct chronic inflammation and hyperplasia (liver) and tubular regenerative hyperplasia and hyperbasophilia and megalocytosis (kidneys) at doses of 125 mg/Kg and higher (lower doses not analysed histologically). The histopathologic findings are mirrored by significant effects in clinical chemistry parameters indicative for liver and kidney lesions starting at 16 and 32 mg/Kg respectively.

In contrast to these findings Merrick (1991) / (Sprague Dawley rat, 90 d repeated dose study, gavage, OECD 408) reports cardiopathic effects of 1,2,3-trichloropropene in the rat down to a concentration of 1.47 mg/Kg bw/d but this lesion shows a very uncommon dose response correlation. In addition the complete absence of cardiac effects in a 120 d gavage study (see above), in all subchronic inhalation studies (see chapter 7.5.3) and even in a 2 year chronic gavage study at comparable dose levels (see chapter 7.7: National Toxicology Program (1993) / Rat and Mouse (3 - 30 and 6 - 60 mg/Kg bw/d, respectively)) renders the correlation between the cardiopathic effects and the 1,2,3 -trichloropropane exposition questionable. Beside this unclear finding the study also showed liver effects (raised ALT and AST levels at 117.94 mg/Kg bw in female rats only; raised values in males were compromised by very high ALT and AST levels in male controls, mirrored by uncommon histopathological findings in this control group). Villeneuve (1985) / (rat, repeated dose toxicity, subchronic, 90 d feeding study) is only available as short summary, lacking histopatholigical data but marking also the liver and the kidneys as primary target organs for repeated dose toxicity of 1,2,3-trichloropropane.

So it can be summarized that liver and kidneys are main target organs of subchronic repeated dose toxicity of 1,2,3-trichloropropane with effects down to 8 mg/Kg bw/day in the rat. The cardiopathic findings of (1991) are disregarded. As the noted effects at 8 mg/Kg bw/day are only liver weight changes and as significant changes in clinical chemical parameters are seen only at 16 mg/Kg (and higher) 1,2,3-trichloropropane should be classified as STOT RE2 concerning oral repeated dose toxicity.

As 1,2,3-trichlororpropane will be classified as genotoxic carcinogen and therefore a strict DMEL will be derived, the corresponding risk management measures will surely be sufficient to cover the risk that stems from the oral toxicity of 1,2,3-trichloropropane after repeated exposure for both workers and general public.

 

- Repeated dose toxicity, dermal: No study on dermal toxicity of 1,2,3 -trichloropropane after repeated dermal exposure could be retrieved. Given the low quotient of acute oral to acute dermal toxicity a high bioavailability via the dermal route should be expected, that is nevertheless somewhat lower than via the oral route. As the distribution of 1,2,3-trichloropropane is swift comparable systemic effects as seen in oral repeated dose studies are to be expected also for the dermal route of exposure but a somewhat higher doses. Given the results from skin irritation, very likely no local effects are to be expected at doses that would inflict systemic effects. Therefore 1,2,3-trichloropropane should be classified as STOT RE2 concerning dermal repeated dose toxicity.

As 1,2,3-trichlororpropane will be classified as genotoxic carcinogen and therefore a strict DMEL will be derived, the corresponding risk management measures will surely be sufficient to cover the risk that stems from the dermal toxicity of 1,2,3-trichloropropane after repeated exposure for both workers and general public.

 

- Repeated dose toxicity, inhalation: The NOAEC of 6 mg/m³ (1.0 ppm) is based on the absence of treatment related effects on the nasal tissues in rats as described in DOW HET-K-002524-006 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity lower doses). Histopathologic examinations of the nasal tissues revealed very slight exposure-related changes in the olfactory epithelium of rats in the 3 ppm and 10 ppm groups, as well as in mice in the 10 ppm group. Similar effects on the olfactory epithelium had previously been found in rats and mice exposed to 13 ppm TCP vapors in a previous study; more pronounced effects on nasal tissues occurred in animals exposed t o 40 or 132 ppm (DOW HET-K-002524-004 / (F344 rat and B6C3F1 mouse, 14d repeated dose inhalation toxicity, higher doses)). In the latter study liver weight effects were seen at 780 mg/m³ (132 ppm) in rats. A comparable NOAEC of 9 mg/m³ (1.5 ppm) that is nevertheless based on liver effects can be deduced from Monsanto (1983) / key (Sprague-Dawley rats, 13 wks repeated dose inhalation study) in combination with Rusch (1979) / key (Sprague-Dawley rats, 13 wks repeated dose inhalation study). Both studies have been carried out with the same strain under comparable exposure conditions. In the former study no adverse effects were seen at the high dose of 9 mg/m³ while in the latter liver weights at 5 ppm and corresponding histologic findings were seen in: Histopathological examinations revealed treatment related findings in the liver and lungs of all treated males and lungs and spleen of all treated females. They consisted of mild centrilobular to midzonal hepatocellular hypertrophy (liver), mild to marked peribronchial lymphoid hyperplasia (lung), and mild to marked extramedullary hematopoiesis and the severity of all this effects was raised dose dependently.

So it can be summarized that nasal tissues, liver and kidneys are main target organs of subchronic repeated dose toxicity of 1,2,3-trichloropropane after inhalation with effects 1.0 ppm in the rat. only liver weight changes and as significant changes in clinical chemical parameters are seen only at 16 mg/Kg (and higher) 1,2,3-trichloropropane should be classified as STOT RE1 concerning repeated dose inhalation toxicity.

As 1,2,3-trichlororpropane will be classified as genotoxic carcinogen and therefore a strict DMEL will be derived, the corresponding risk management measures will surely be sufficient to cover the risk that stems from the inhalation toxicity of 1,2,3-trichloropropane after repeated exposure for both workers and general public.

Repeated dose toxicity: via oral route - systemic effects (target organ) digestive: liver; urogenital: kidneys

Repeated dose toxicity: inhalation - systemic effects (target organ) digestive: liver; respiratory: nose; urogenital: kidneys

Justification for classification or non-classification

Based on the above stated results on oral and dermal repeated dose toxicity 1,2,3-trichloropropane should be classified as STOT RE2 (H373: May cause damage to liver and kidneys through prolonged or repeated exposure via the oral or the dermal route) concerning oral or dermal exposure. Based on the above stated results on repeated dose inhalation toxicity 1,2,3-trichloropropane should be classified as STOT RE1 (H372: Causes damage to nasal tissues, liver and kidneys) through prolonged or repeated exposure via inhalation) concerning repeated inhalative exposure.