Santicizer 2148

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990-01-17 to 1990-10-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OTS 798.2650 (90-Day Oral Toxicity in Rodents)

Version / remarks:

EPA TSCA Guildelines, 40 CFR PART 798.2650

Deviations:

not specified

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Phenol

EC Number:

203-632-7

EC Name:

Phenol

Cas Number:

108-95-2

Molecular formula:

C6H6O

IUPAC Name:

phenol

Constituent 2

Reference substance name:

1-chlorododecane

Molecular formula:

C12H25Cl

IUPAC Name:

1-chlorododecane

Constituent 3

Reference substance name:

1-Dodecanol

Cas Number:

112-53-8

Molecular formula:

C12H26O

IUPAC Name:

1-Dodecanol

Constituent 4

Reference substance name:

1-Tetradecanol

Cas Number:

112-72-1

Molecular formula:

C14H30O

IUPAC Name:

1-Tetradecanol

Constituent 5

Reference substance name:

triphenyl phosphate

Cas Number:

115-86-6

Molecular formula:

C18H15O4P

IUPAC Name:

triphenyl phosphate

Constituent 6

Reference substance name:

-

EC Number:

431-760-5

EC Name:

-

Cas Number:

27460-02-2

Molecular formula:

C24H35O4P

IUPAC Name:

dodecyl diphenyl phosphate

Constituent 7

Reference substance name:

diphenyl tetradecyl phosphate

Cas Number:

142474-86-0

Molecular formula:

C26H39O4P

IUPAC Name:

diphenyl tetradecyl phosphate

Constituent 8

Reference substance name:

Didodecyl phenyl phosphate

Cas Number:

56827-93-1

Molecular formula:

C30H55O4P

IUPAC Name:

Didodecyl phenyl phosphate

Test material form:

liquid

Test animals

Species:

rat

Strain:

other: Crl:CD®BR

Details on species / strain selection:

Rats were chosen as the appropriate test species because they have been used historically in safety evaluation studies and are recommended by appropriate regulatory agencies.

Sex:

male/female

Details on test animals or test system and environmental conditions:

A total of 64 male and 63 female Sprague-Dawley rats, Crl:CD®BR, was received on March 13, 1990, from Charles River Laboratories, Inc., Raleigh, North Carolina.
The animals were approximately 4 weeks of age at the time of receipt.

At initiation of dosing, the rats were approximately 6 weeks of age with body weights ranging from 184.1 to 223.7 g for males and from 145.3 to 189.4 g for females
All animals were acclimated to the laboratory environment for approximately 2 weeks and examined for general physical condition and any clinical signs of disease by a staff veterinarian prior to release from quarantine.

Rats were housed in stainless-steel, hanging, wire-mesh cages (2 per cage); following randomization, the animals were housed individually.

During the quarantine and study periods, the room temperature and relative humidity were recorded twice daily. Environmental controls were set to maintain the temperature and humidity at 72±6°F and 50±20%, respectively. An artificial light cycle of 12 hours light and 12 hours dark was maintained by an automatic timing device.

Administration / exposure

Route of administration:

oral: gavage

Details on route of administration:

The oral gavage route was chosen because potential human exposure is by the oral route.

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
The desired amount of the test material was weighed on an appropriate balance into a beaker and then transferred into a precalibrated beaker. The original beaker was then washed with the vehicle and the wash was poured into the precalibrated beaker in order to ensure that all the residual test material was transferred. Additional corn oil was added to the test material in the precalibrated beaker to attain the desired volume, and the test material and corn oil were mixed on a magnetic stirrer for approximately 30 minutes. The mixtures were then transferred into clear jars for dosing. Dosing formulations were mixed weekly.

The vehicle control and test material were adminstered in the same week as they were formulated. Dose mixtures were removed from refrigeration 1 hour prior to dosing and stirred continuously during dosing. The dose administered was calculated and adjusted weekly for each animal based on the most recently recorded body weight.

VEHICLE
- Justification for use and choice of vehicle (if other than water): Corn Oil, justification not specified
- Concentration in vehicle: 0, 25, 70, or 200 mg/mL for Groups 1, 2, 3, and 4, respectively.
- Amount of vehicle (if gavage): 10 mL/Kg
- Lot/batch no. (if required): 9G 25 14:25
- Purity: assumed to be 100%

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Verification of the concentration of dosing mixtures was performed on samples collected during Weeks 1 and 4 of study. The analytical chemistry methods are appended to the Analytical Chemistry Report

Duration of treatment / exposure:

at least 28 days

Frequency of treatment:

daily

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0 mg/kg bw/day (nominal)

Remarks:

Group 1 (Control)

Doses / concentrations 2

Dose / conc.:

250 mg/kg bw/day (nominal)

Remarks:

Group 2 (Low dose)

Doses / concentrations 3

Dose / conc.:

700 mg/kg bw/day (nominal)

Remarks:

Group 3 (Mid dose)

Doses / concentrations 4

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Remarks:

Group 4 (High dose)

No. of animals per sex per dose:

10/rats/sex/dose

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
- Rationale for animal assignment (if not random): Rats were selected for the study using a computer generated weight-randomization procedure which assigned them to treatment groups by eliminating the animals with extreme body weights (± 2 S.D. of the mean body weight).
- Fasting period before blood sampling for clinical biochemistry: Not specified

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: All rats observed twice daily for mortality and moribundity

DETAILED CLINICAL OBSERVATIONS: Yes. Clinical observations for obvious indications of a toxic and/or pharmacologic effect were performed 1 to 2 hours postdose and effects and other pertinent observations recorded.
- Time schedule: 1 to 2 hours post dose

BODY WEIGHT: Yes
- Time schedule for examinations: Individual body weights were recorded prior to initiation of dosing, at weekly intervals thereafter through week 4, and at termination.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes. Individual food consumption was measured weekly.

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Not specified

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Ophthalmoscopic examinations were performed on each animal prior to treatment and during Week 4 (prior to scheduled necropsy) using an indirect ophthalmoscope and 1% Mydriacyl® for pupil dilation
- Dose groups that were examined: all animals

HAEMATOLOGY: Yes
- Time schedule for collection of blood: During the week prior to initiation of dosing (week -1) and during the last week of treatment (week 4)
- Anaesthetic used for blood collection: Yes (ketamine)
- Animals fasted: Yes overnight fast
- How many animals: Not specified
- Parameters checked in table [No.2] were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: During the week prior to initiation of dosing (week -1) and during the last week of treatment (week 4)
- Animals fasted: Yes overnight fast
- How many animals: Not specified
- Parameters checked in table [No.3] were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

All animals not selected for the study were sacrificed on Day 8 of the study by CO2 inhalation and exsanguination

A necropsy was performed on the one animal which was designated an unscheduled death

After at least 28 days of treatment, all surviving rats were weighted, anesthetised with sodium pentobarbital, and exsanguinated. A necropsy was conducted on each animal

A necropsy included an examination of the following:
External surface of the body
All orifices
Cranial cavity
Carcass
External surface of the brain; the external surface of the spinal cord and cut surfaces of the brain and spinal cord were examined at the time of tissue trimming, should histopathology require
Nasal cavity and paranasal sinuses
Thoracic, abdominal, and pelvis cavities and their viscera
Cervical tissues and organs

Statistics:

Weekly (weeks 1-4) and total (weeks 1-4) food consumption, clinical pathology data (except cell morphology data), and organ weight data of the control group were compared statistically to the data of the compound treated groups of the same sex. If variances of untransformed data were heterogenous, the data were transformed to achieve variance homogeneity. When the series of transformations was unsuccessful in achieving variance homogeneity, analyses were performed on rank transformed data. Group comparisons were routinely performed at the 5% two-tailed probability level.

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Most of the observations noted for the nasal-orbital area in rats of both sexes of all dose groups were the result of trauma induced by blood collection on Week 4.

Urine stains were noted during cageside observations and weekly physical examinations. Although urine stains were noted among all groups, the observation occurred at a higher incidence in Group 4, suggesting a treatment-related effect (Table 2).

Pre- and post-dose incidences of salivation were observed in the Group 4 males and females (Table 3). Due to the inconsistent distribution over time, the noted salivation, although related to treatment, was judged to be a direct effect of the compound on the oral cavity as the result of dosing technique and/or conditioned response of the rats to dosing.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

No compound-related deaths were observed through the study period. One Group 3 female (04934) died during Week 4 following scheduled blood collection; the death being attributed to the blood collection procedure and was considered to be accidental.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Mean body weights were comparable between treated and contro groups for both sexes at all intervals.

Food consumption and compound intake (if feeding study):

not specified

Description (incidence and severity):

Mean food consumption values were significantly increased as compared to control values for Group 4 animals at weeks 2 and 3, Group 4 females at week 4, and Group 3 females at week 3. Significant increases compared to control values were observed in the total food consumption values (weeks 1-4) for Group 4 animals and Group 3 females. Notably, increased food consumption in treated animals was not accompanied by increased body weight gain.

Food efficiency:

not examined

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

not specified

Ophthalmological findings:

effects observed, non-treatment-related

Description (incidence and severity):

No treatment-related ophthalmoscopic abnormalities were observed.

1 Male (Group 1 04881) - scarring of the left cornea and retinal degeneration of the left fundus
1 female (Group 2 04917) observed scarring of the left cornea

Haematological findings:

no effects observed

Description (incidence and severity):

No significant differences were observed in treated groups when compared with concurrent control animals. There was no evidence of an effect that could be attributed to treatment with the test material.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

No significant differences were observed in treated groups when compared with concurrent control animals. There was no evidence of an effect that could be attributed to treatment with the test material.

Week 4 cholinesterase values were increased substantially fro Group 1-4 females as compared to week -1. Such increases are not unusual for maturing female rats of this strain, and the lack of a similar response in male rats was also considered typical.

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

The absolute and relative liver weight values were significantly increased as compared to control values for Group 4 animals. Additionally, the mean liver-to-terminal body weight value of the Group 3 males was significantly increased as compared to control.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Observations noted in the liver of animals sacrificed at termination included pale or pale area, cyst, and raised area. In addition, a mass was observed in the liver of one Group 2 female rat. Findings in the kidney included pale, dilated pelvis, and cyst. Neither the incidence nor distribution of the liver or kidney findings among the groups indicated a treatment-related effect. All other observations noted for the animals sacrificed at termination are considered to be incidental. The Group 3 female that died (accidental death) during week 4 had no observations at necropsy.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

All lesions noted during the terminal sacrifice were considered to be incidental findings or part of spontaneous disease complexes pf laboratory rats. There was no microscopically discernible increase in the incidence or severity of these lesions in the treated animals. The lesions were typical of those expected in a group of laboratory rats of that age.

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Effect levels

1

Key result

Dose descriptor:

NOEL

Effect level:

250 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Systemic Toxicity

2

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 700 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Systemic Toxicity

Target system / organ toxicity

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

2 000 mg/kg bw/day (nominal)

System:

hepatobiliary

Organ:

liver

Treatment related:

yes

Dose response relationship:

yes

Relevant for humans:

not specified

Any other information on results incl. tables

Table 4. Number of Animals Exhibiting Urine Stains^a
Week(s)	Group 1 (Control)		Group 2 (250 mg/Kg/day)		Group 3 (700 mg/Kg/day)		Group 4 (2000 mg/Kg/day)
	Male	Female	Male	Female	Male	Female	Male	Female
1	0	0	0	0	0	0	1	0
2	0	0	0	0	0	1	2	2
3	1	0	0	0	0	0	4	1
4^b	1	0	1	0	1	0	3	0
1-4	1	0	1	0	1	1	6	2

^a Number of animals observed to have urine stains at least once during the designated interval

^b Week 4 includes 2 days of Week 5 (until termination)

 

Table 5. Number of Animals Exhibiting Salivation^a
Week(s)	Pre-dose		Post-dose
	Male	Female	Male	Female
1	10	10	0	0
2	4	4	4	2
3	0	0	0	3
4	0	0	1	0
1-4	10	10	4	3

^a Number of animals observed pre- or post-dose salivation at least once during the designated interval

Table 6. Mean body weight change (g) – 28 day tox study in rats with XP2563 – males

Group and dose level (mg/kg)		Mean body weight change (g)
		Week 0-1	Week 1-2	Week 2-3	Week 3-4^a	Weeks 0-4
1 – 0.000	Mean	62.7	49.0	44.8	24.3	181.0
	sd	5.77	8.00	4.79	4.88	13.82
	N	10	10	10	10	10
2 – 250.000	Mean	58.4	46.5	41.9	24.0	170.8
	sd	6.76	8.80	7.23	8.40	19.33
	N	10	10	10	10	10
3- 700.000	Mean	60.7	52.4	41.5	21.1	175.8
	sd	8.26	8.85	8.00	12.55	25.58
	N	10	10	10	10	10
4 – 2000.000	Mean	54.7	51.2	47.5	18.5	181.9
	sd	4.37	7.27	6.93	9.70	22.55
	N	10	10	10	10	10

   

Table 7. Mean body weight change (g) – 28 day tox study in rats with XP2563 – females

Group and dose level (mg/kg)		Mean body weight change (g)
		Week 0-1	Week 1-2	Week 2-3	Week 3-4^a	Weeks 0-4
1 – 0.000	Mean	26.3	17.8	22.9	7.3	74.4
	sd	5.36	7.04	4.71	5.68	8.57
	N	10	10	10	10	10
2 – 250.000	Mean	29.1	19.3	20.8	7.4	76.8
	sd	5.47	4.46	2.24	9.12	9.16
	N	10	10	10	10	10
3- 700.000	Mean	28.6	20.4	21.1	12.3	83.0
	sd	6.12	3.33	6.42	4.65	9.41
	N	10	10	10	9	9
4 – 2000.000	Mean	25.3	19.3	19.7	9.6	74.0
	sd	11.63	8.21	7.20	7.66	14.49
	N	10	10	10	10	10

a – animals were fasted overnight prior to blood collection during Week 4

 

Table 8. Mean food consumption and standing deviations (g/wk) – 28 day tox study in rats with XP2563 – males

Group and dose level (mg/kg)		Mean food consumption and standing deviations (g/wk)				Mean total food consumption and sd (g)
		Week 1	Week 2	Week 3	Week 4^a	Weeks 1-4
1 – 0.000	Mean	156.6	154.4	147.1	125.5	583.6
	sd	10.79	16.73	12.52	10.53	43.24
	N	10	10	10	10	10
2 – 250.000	Mean	152.9	148.3	149.7	127.5	578.4
	sd	9.35	11.55	13.75	12.36	37.78
	N	10	10	10	10	10
3- 700.000	Mean	156.0	160.3	152.4	126.0	594.7
	sd	9.01	9.62	16.14	11.05	33.86
	N	10	10	10	10	10
4 – 2000.000	Mean	157.1	170.6	170.3	138.6	636.6*
	sd	6.79	13.7	13.30	15.37	41.68
	N	10	10	10	10	10

 

Table 9. Mean food consumption and standing deviations (g/wk) – 28 day tox study in rats with XP2563 – females

Group and dose level (mg/kg)		Mean food consumption and standing deviations (g/wk)				Mean total food consumption and sd (g)
		Week 1	Week 2	Week 3	Week 4^a	Weeks 1-4
1 – 0.000	Mean	104.5	100.5	100.2	86.4	391.8
	sd	11.36	15.21	11.64	8.71	43.02
	N	10	10	10	10	10
2 – 250.000	Mean	112.9	112.4	108.2	93.5	429.9
	sd	11.09	10.34	9.85	8.98	25.24
	N	10	10	9	10	9
3- 700.000	Mean	112.9	114.8	121.3*	104.6	454.0*
	sd	10.48	12.00	19.02	28.89	64.72
	N	10	10	10	9	9
4 – 2000.000	Mean	115.8	127.4*	125.6*	107.1*	482.2*
	sd	19.38	25.08	17.67	14.47	54.41
	N	10	9	10	10	9

a – animals were fasted overnight prior to blood collection during Week 4

* Significantly different from control values, p≤0.05

Table 10. Gross Pathological Incidence Summary
Organ and Key Word(s) or Phrase	Number of Animals Affected
	Males				Females
	Control	250 mg/Kg/day	700 mg/Kg/day	2000 mg/Kg/day	Control	250 mg/Kg/day	700 mg/Kg/day	2000 mg/Kg/day
Number	10	10	10	10	10	10	9	10
Liver
Number Examined	10	10	10	10	10	10	9	10
Not Remarkable	9	10	8	8	9	8	9	10
Pale Area	1	0	1	1	0	0	0	0
Cyst	0	0	0	0	1	0	0	0
Pale	0	0	0	0	0	1	0	0
Raise Area	0	0	1	1	0	0	0	0
Mass	0	0	0	0	0	1	0	0
Kidney
Number Examined	10	10	10	10	10	10	9	10
Not Remarkable	10	9	6	8	9	10	8	10
Cyst	0	0	2	0	0	0	1	0
Pelvis Dilated	0	0	1	1	0	0	0	0
Pale	0	1	1	1	1	0	0	0

Table 11. Absolute Liver Weight, Mean Liver to Terminal Body Weight, and Mean Liver to Brain Weight Observations
Organ	Males				Females
	Control	250 mg/Kg/day	700 mg/Kg/day	2000 mg/Kg/day	Control	250 mg/Kg/day	700 mg/Kg/day	2000 mg/Kg/day
Number	10	10	10	10	10	10	9	10
Absolute Liver Weight
Number in Group	10	10	10	10	10	10	9	10
Mean	11.49	11.22	11.97	12.70*	7.46	7.94	7.94	8.93*
Standard Deviation	0.80	1.28	1.26	1.22	1.14	0.64	0.61	0.93
Liver to Terminal Body Weight
Number in Group	10	10	10	10	10	10	9	10
Mean	3.022	3.191	3.352*	3.606*	3.311	3.402	3.423	3.965*
Standard Deviation	0.137	0.222	0.209	0.199	0.405	0.228	0.203	0.387
Liver to Brain Weight
Number in Group	10	10	10	10	10	10	9	10
Mean	5.137	5.301	5.708	6.081*	3.809	3.917	4.042	4.435*
Standard Deviation	0.496	0.592	0.706	0.485	0.561	0.301	0.401	0.502

* Significantly different from control p≤0.05

Applicant's summary and conclusion

Conclusions:

Oral administration of XP2563 to rats at a dose level of 2000 mg/kg/day for at least 28 days was associated with an increased incidence of urine stains and increases in absolute and relative liver weights. Increased food consumption was observed at the 700 and 2000 mg/kg/day dose levels. Under the conditions of this study, and dose level of 700 mg/kg/day elicited increases in food consumption only, and therefore is considered to be the no-observable-adverse-effect-level (NOAEL); the dose of 250 mg/kg/day did not elicit any consistent or apparent treatment-related changes; therefore, 250 mg/kg/day is considered to be the no-observable-effect-level (NOEL)

Executive summary:

80 young adult rats were stratified by weight, randomly assigned to 1 of 4 groups (10 rats/sex/group), and dosed daily, by oral gavage, with XP2563 or corn oil at a dose volume of 10.0 ml/kg for at least 28 days. Group assignments were as follows: Group 1 (vehicle control), Group 2 (250 mg/kg/day), Group 3 (700 mg/kg/day), Group 4 (2000 mg/kg/day).

Clinical observations, periodic body weight and food consumption determinations, clinical pathology tests, ophthalmoscopic examinations, selected organ weights, and microscopic examination of selected tissues and organs were utilised to detect treatment-related effects.

There were no treatment-related deaths during the study. One Group 3 female (04934) died during Week 4 following scheduled blood collection; the death is attributable to the blood collection procedure and is considered to be accidental. No compound-related effects were noted in body weights, clinical pathology tests, ophthalmoscopic examinations, gross necropsy findings, or microscopic examination of selected tissues and organs.

Treatment-related clinical signs included an increased incidence of urine stains in Group 4 animals. In addition, pre- and postdose salivation was noted in several Group 4 animals. It is thought that the salivation was a direct result of the test material on the oral cavity due to the dosing technique and/or a conditioned response to the dosing procedure. Treatment-related increases in mean food consumption values were noted for Group 4 animals at Weeks 2 and 3; Group 4 females at Week 4; and Group 3 females at Week 3, total food consumption values (Weeks 1-4) were significantly higher than controls for Group 4 animals and Group 3 females. In addition, significant treatment-related increases were noted in the mean absolute and relative liver weight values for Group 4 animals. However, the changes in liver weight could not be correlated with any microscopic finding in this tissue or with any changes in clinical pathology parameters diagnostic of hepatic dysfunction.

In conclusion, oral administration of XP2563 to rats at a dose level of 2000 mg/kg/day for at least 28 days was associated with an increased incidence of urine stains and increases in absolute and relative liver weights. Increased food consumption was observed at the 700 and 2000 mg/kg/day dose levels. Under the conditions of this study, and dose level of 700 mg/kg/day elicited increases in food consumption only, and therefore is considered to be the no-observable-adverse-effect-level (NOAEL); the dose of 250 mg/kg/day did not elicit any consistent or apparent treatment-related changes; therefore, 250 mg/kg/day is considered to be the no-observable-effect-level (NOEL).