O-isopropyl ethylthiocarbamate

Endpoint summary

Description of key information

 -NOAEL of 125 mg/kg bw/day was established based on no effects observed for Butan-1-ol (Butyl alcohol) as a main constituent of IPETC/ O-isopropyl ethylthiocarbamate. LOAEL  of 500 mg/kg bw/day was established based on clinical signs of SNC depression (ataxia and hypoactivity).
-NOAEC of 12.47 mg/m3 was established based on no effects  in rats.
- The NOAEL was 144.43 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

Butan-1-ol (Butyl alcohol) is both reagents used in the manufacture of IPETC/ O-isopropyl ethylthiocarbamate . Therefore, Butan-1-ol (Butyl alcohol) need to be considered in the assessment of IPETC/ O-isopropyl ethylthiocarbamate .

Qualifier:

equivalent or similar to guideline

Guideline:

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

Principles of method if other than guideline:

Four groups of male and female rats (30/sex/group) were administered daily by gavage 0, 30, 125 or 500 mg/kgbw/d for either 6 or 13 weeks.

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, Inc., Portage, Michigan, U.S.A.
- Age at study initiation: 36-37 d
- Mean weight at study initiation: males 90 g, females 86 g
- Housing: individually
- Diet (e.g. ad libitum): Purina Certiofied Rodent Laboratory Chow #5002 (pellet)
- Water (e.g. ad libitum): filtered municipal water
- Acclimation period: 7 days before the pretreatment week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 +/- 1
- Humidity (%): 48 +/- 9
- Photoperiod (hrs dark / hrs light): 12:12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Dosing solutions of butanol in deionized water were used.

VEHICLE
- Concentration in vehicle: not specified
- Amount of vehicle (if gavage): 10 ml/kg was the constant dosing volume

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

GC-FI

Duration of treatment / exposure:

6 (interim sacrifice) or 13 weeks

Frequency of treatment:

daily

Remarks:

Doses / Concentrations:
0, 30, 125, 500 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

30 (further 10 were sacrificed prior to dosing for determination of clinicopathological baseline levels)

Control animals:

yes, concurrent vehicle

Positive control:

no data

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: twice daily

BODY WEIGHT: Yes
- Time schedule for examinations: Body weights were recorded weekly


FOOD CONSUMPTION: Yes
-Time schedule: Food consumption was recorded weekly


OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Ophthalmic examination was conducted prior to treatment and during week 13 before final necropsy.
- Dose groups that were examined: no data


HAEMATOLOGY: Yes
- Time schedule for collection of blood: before the start of the study, during week 6 and during week 13
- Anaesthetic used for blood collection: No data
- Animals fasted: No data
- How many animals: 10 males and 10 females
- parameters: hemoglobin ( HGB), hematocrit (PCV), erythrocyte count (RBC), mean cell volume (MCV), mean cell hemoglobin (MCH),mean cell hemoglobin concentration (MCHC) total and differential leucocyte counts (WBC), estimated platelet count (PLT)


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: before the start of the study, during week 6 and during week 13
- Animals fasted: No data
- How many animals: 10 males and 10 females
- parameters: alkaline phosphatase (Alk phos) blood urea nitrogen (BUN), glutamate pyruvate transaminase (SGPT), glutamate oxalacetate transaminase (SGOT), glucose (Gluc), total protein (TP), albumin (Alb), A/G ratio (calculated), globulin (calculated), total bilirubin (Tot. bili.), sodium (Na), potassium (K ), chloride (Cl), calcium (Ca), inorganic phosphate (Phos), carbon dioxide (TCO2), total serum cholesterol (Chol), creatinine.


URINALYSIS: Yes
- Time schedule for collection of urine: before the start of the study, during week 6 and during week 13
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- parameters: pH, specfic gravity, glucose, protein, ketones, bilirubin, urobilinogen, microscopy of sediment


NEUROBEHAVIOURAL EXAMINATION: No data

Sacrifice and pathology:

GROSS PATHOLOGY: Yes: Ten male and ten female rats from each group were necropsied on study days 43 to 44 and the remaining animals on study days 92 to 93. Gross pathology of all animals was assessed and organs from animals necropsied on study days 92 to 93 were weighed.
HISTOPATHOLOGY: Yes: A complete histopathological investigation was made of all animals of the control and high-dose groups. In the low and mid-dose groups, histopathology included the liver, kidney, and heart from all animals and all gross lesions. All animals found dead or killed in extremis were also microscopically examined.

Statistics:

no data

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

no effects observed

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:

no effects observed

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
Ataxia and hypoactivity (lasting less than 1 h) were observed 2 to 3 minutes after dosing in both sexes of the high-dose group (500 mg/kg bw/d) during the final 6 weeks of dosing. Such ataxia and hypoactivity are typically seen following high oral doses of alcohols. The rapid induction/remission of these effects and the reported increased incidence after the interim kill may be due to the fact that personnel were able to collect post-dose observations more quickly since fewer animals required dosing.
No significant changes between treated groups and controls were observed concerning mortality (three rats were found dead or sacrificed in extremis, but these deaths could not be attributed to the test article.).

BODY WEIGHT AND WEIGHT GAIN
no significant changes between treated groups and controls were observed

FOOD CONSUMPTION
no significant changes between treated groups and controls were observed

OPHTHALMOSCOPIC EXAMINATION
no significant changes between treated groups and controls were observed

HAEMATOLOGY
At the interim clinical pathological evaluation, red blood cell count (RBC) packed cell volume (PCV), and hemoglobin (HGB) averages of the 500 mg/kg/day dose group females were 5% below control averages. Although these differences were statistically significant, they were small and no differences between the parameters were observed in the males of the interim evaluation or between control and treated groups of either sex at the final evaluation. Therefore, even if the lower red blood cell parameters in the 500 mg/kg/day females were an actual treatment-related effect, it was small and transitory and thus not considered as adverse.

CLINICAL CHEMISTRY
no significant changes between treated groups and controls were observed

URINALYSIS
no significant changes between treated groups and controls were observed

ORGAN WEIGHTS
no significant changes between treated groups and controls were observed

GROSS PATHOLOGY
no significant changes between treated groups and controls were observed

HISTOPATHOLOGY: NON-NEOPLASTIC
no significant changes between treated groups and controls were observed

Dose descriptor:

NOAEL

Effect level:

125 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed

Dose descriptor:

LOAEL

Effect level:

500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: clinical signs of SNC depression (ataxia and hypoactivity)

Critical effects observed:

not specified

Conclusions:

Dose or concentration at which no toxic effects were observed:
NOAEL: 125 mg/kg/day
LOAEL: 500 mg/kg/day

Executive summary:

NOAEL of 125 mg/kg bw/day was established based on no effects observed for Butan-1-ol (Butyl alcohol) as a main constituent of IPETC/ O-isopropyl ethylthiocarbamate.

LOAEL of 500 mg/kg bw/day was established based on clinical signs of SNC depression (ataxia and hypoactivity).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

125 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

repeated dose toxicity: inhalation, other

Remarks:

combined repeated dose and carcinogenicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Propan-2-ol (Isopropyl alcohol) is both reagents used in the manufacture of IPETC/O-isopropyl ethylthiocarbamate. Therefore, Propan-2-ol (Isopropyl alcohol) need to be considered in the assessment of IPETC/O-isopropyl ethylthiocarbamate

Qualifier:

according to guideline

Guideline:

other: OECD 451

Deviations:

yes

Remarks:

Not monitoring food consumption

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague Dawley Inc. Indianapolis, IN
- Age at study initiation: 28-30 days old
- Weight at study initiation: 121.2-165 g (males) and 93.6 - 124.3 g (females) on the first day of exposure
- Fasting period before study: None
- Housing: 2 per cage in stainless steel, wire mesh cages
- Diet (e.g. ad libitum): Pelleted, certified AGWAY PROLAB animal diet rat 3000 ad libitum
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 3 weeks


ENVIRONMENTAL CONDITIONS
- Temperature : 17 - 26 °C
- Humidity (%): 40-70
- Air changes (per hr): Not reported
- Photoperiod (hrs dark / hrs light): 12-12

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: Not reported

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Inhalation chamber (Wahmann Manufacting company, Timonium, MD)
- System of generating particulates/aerosols: liquid isopropanol was metered from a container by piston pump
- Temperature in air chamber: 22 +/- 4 degrees
- Air flow rate: 1000 l/min for first month and 900 l/min thereafter
- Air change rate: 14 air changes/hr for first month and 12.5 air changes/hr thereafter
- Method of particle size determination: not reported
- Treatment of exhaust air: not reported


TEST ATMOSPHERE
- Brief description of analytical method used: liquid isopropanol was metered from a container by piston pump into a heated glass evaporator and the temperature of the evaporators was maintained at the lowest level to sufficiently vaporize the test substance.
- Samples taken from breathing zone: yes

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Each exposure chamber was analyzed for isopropanol twice each hour by flame ionization gas chromatography.

Duration of treatment / exposure:

at least 104 weeks

Frequency of treatment:

6 hours/day, 5 days/week

Remarks:

Doses / Concentrations:
0, 500, 2500, 5000 ppm
Basis:
nominal conc.

No. of animals per sex per dose:

65 sex/dose for the core group and 10 sex/dose for the interm sacrifice

Control animals:

yes, sham-exposed

Details on study design:

- Rationale for animal assignment (if not random): animals were assigned to 3 exposure groups and a control group using a sacrificed randomization procedure based on body weight
- Rationale for selecting satellite groups: 10 sex/group were sacrified in the middle of the study

Positive control:

None

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice a day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly for the first 14 weeks and then every other week after

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No data

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: No data

WATER CONSUMPTION: No data

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: prior to experiment, and during weeks 71, 80, 104, and 107
- Dose groups that were examined: all rats


HAEMATOLOGY: Yes
- Time schedule for collection of blood: 13 months, 19 months, and 25 months
- Anaesthetic used for blood collection: Yes (identity) methoxyflurane
- Animals fasted: No
- How many animals: 10 sex/dose level

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: week 57
- Animals fasted: No
- How many animals: 10 sex/dose group

URINALYSIS: Yes
- Time schedule for collection of urine: week 57, 59, 74, and 104
- Metabolism cages used for collection of urine: No
- Animals fasted: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Other examinations:

None

Statistics:

The data for the 3 treatment groups and the control group were compared with Levene's test for equality of variances, analysis of variance (ANOVA), and t-tests. The nonparmetric data were statistically evaluated with the Kruskal-Wallis test followed by the Mann-Whitney U-test. Mortality was analysed by life-table analyses. Incidence data were compared using Fishers exact test.

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:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

effects observed, treatment-related

Behaviour (functional findings):

no effects observed

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
- Mortality rates for males in the 0, 500, 2500, and 5000 ppm groups were 82, 83, 91, and 100%, respectively. For females, 54, 48, 55, and 69%. No significant differences were noted for male rats from 500 or 2500 groups or any female rats.
-In males and females exposed to 5000 ppm; hypoactivity, lack of a startle reflex, and narcosis were identified. In males and females exposed to 2500 ppm; hypoactivity, and a lack of a startle reflex were observed. No effects in 500 ppm group. During non-exposure periods in males 5000 ppm group emaciation and dehydration was observed. In males and females in 5000 ppm there was greater numbers of rats with urine stains and swollen periocular tissue (females only). Females in the 2500 ppm group also had increased incidence of urine stains.

BODY WEIGHT AND WEIGHT GAIN
-Decreased body weights were observed for male rats from the 5000 ppm group in the first and second weeks of exposure, and then increased and at the end of week 6 body weights were increased significantly over the control group. Increased body weights were also noted for male rats from the 2500 ppm group.
-Decreased body weights were observed for female rats from the 5000 ppm group in the first and second weeks of exposure, and then increased and at the end of week 5 body weights were increased significantly over the control group. Increased body weights were also noted for female rats from the 500 ppm group. At week 72, all female body weights were significantly increased when compared to the control group.

URINALYSIS
-In males in the 5000 ppm group, in weeks 57, 59, 74, and 104 decrease in osmolality and increase in total protein and total volume were reported.
-In females rats in the 5000 ppm group, a decrease in osmolality and an increase in total volume was reported. At week 74, total glucose excreted in the urine was increased for females in the 5000 ppm group.


ORGAN WEIGHTS
- At the interim sacrifice, absolute and relative kidney weights were increased for male rats in the 5000 ppm group. Relative liver weights were increased for male rats in the 2500 ppm group. Concentration-related increases in absolute and relative testes weight was reported for male rats in 5000 ppm group. In females, increases in absolute and relative lung weight for rats in the 5000 ppm was reported.
-At the terminal sacrifice, increase in relative liver weight was noted for male rats in 2500 ppm group. In females, an increase in absolute and relative liver and kidney weights were noted for the 5000 ppm group.


GROSS PATHOLOGY
- At the interim sacrifice, an increase in granular kidneys in male rats from the 2500 and 5000 ppm groups were noted
- At the terminal sacrifice, an increase in granular kidneys in male rats from the 2500 ppm group was noted. Increased frequencies of gross lesions for male rats that died included increase incidence of thickened stomachs, granular kidneys, and color change of the kidneys for animals in 2500 and 5000 ppm groups.
- For females that died before the end of the study, an increased incidence of thickened stomachs was noted for animals from the 5000 ppm group and granular kidneys were noted for animals from the 2500 and 5000 ppm groups.


HISTOPATHOLOGY: NON-NEOPLASTIC
- At the interim sacrifice, male rats from the 5000 ppm group had an increased frequency of testicular seminiferous tubule atrophy.
-Increased frequencies of kidney lesions were observed in male rats in the 2500 and 5000 dose groups that died during the study. Increased in the frequency of mineralization in the heart, aorta, vasculature, stomach, larynx, trachea, lungs, kidney, cornea, and testes was noted for male rats in the 2500 and 5000 ppm dose groups that died during the study. Additionally, basophilic cell foci in the liver, splenic hemosiderosis, rhinitis, and squamous metaplasisa of the respiratory epithelium in the nasal cavity were reported for male rats in the 5000 ppm group that died during the study.
-Increased severity of glomerulosclerosis was observered in female rats in the 5000 ppm group. Renal disease was also increased in female rats in the 5000 ppm group.
- For female rats that died during the study, increased frequencies of mineralization in the heart, aorta, vasculature, stomach, larynx, trachea, lungs and kidney. Increase in myocardial degeneration, atrial thrombosis, splenic hemosiderosis, ocular keratitis, inflammatory and metaplastic changes in the nasal cavity, squamous metaplasia of the respiratory epithelium and glandular ectasia in the gastric mucosa was also evident in females in the 5000 ppm group that died during the study.


HISTOPATHOLOGY: NEOPLASTIC (if applicable)
-Dose-related increase in interstitial cell adenomas of the testis in male rats at interim sacrifice, at the terminal sacrifice, and in male rats that died during the study.

Dose descriptor:

NOEL

Effect level:

500 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: for species specific toxic effects

Dose descriptor:

NOEL

Effect level:

5 000 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: for oncogenicity effects

Dose descriptor:

NOAEL

Effect level:

5 000 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: The report allows the conclusion that there are no substance specific adverse exposure related effects. A NOAEL of 5000 ppm can be derived.

Dose descriptor:

NOAEL

Effect level:

12.47 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Concentrations of 5000 ppm is equal to 12.47 mg/m³ (molecular mass of 60.10 g/mol for Propan-2-ol)

Critical effects observed:

not specified

Conclusions:

The no-observed-effect level (NOEL) for toxic effects for both rats and mice was 500 ppm. The NOEL for oncogenicity effects for both mice and rats was determined to be greater than 5000 ppm.Propan-2-ol (Isopropyl alcohol) is both reagents used in the manufacture of IPETC/ O-isopropyl ethylthiocarbamate. Therefore, Propan-2-ol (Isopropyl alcohol) need to be considered in the assessment of IPETC/O-isopropyl ethylthiocarbamate .

Executive summary:

The inhalation toxicity of IPA( isopropyl alcohol) has been assessed in a 104-week oncogenicity study in rats . This study was conducted according to OECD test guideline 451. IPA was administered by whole-body inhalation to groups of male and female Fischer 344 rats (75 rats/sex) for6 hours/day 5 days/weekfor at least 104 weeks at nominal concentrations of 0 (control), 500, 2500, or 5000 ppm (measure concentrations of0, 504, 2509, or 5031 ppm, respectively). Ten rats/sex/group were assigned to interim sacrifice at Week 73. Animals were monitored for clinical observations, body and organ weights, ophthalmology examinations, hematology, urinalysis and urine chemistry examinations, gross pathology and microscopic examinations. Exposure of rats to IPA vapour for 104 weeks produced clinical signs of toxicity (including hypoactivity, lack of startle reflex, and/or narcosis), changes in body weight, and urinalysis and urine chemistry indicative of kidney changes (decrease in osmolality and increase in total volume and/or protein) in the 2500 and 5000 ppm groups. At terminal sacrifice, increased absolute and relative kidney weights were noted in males at 2500 ppm and females at 5000 ppm. Macroscopic changes such as granular kidney were noted in males and females of 2500 and 5000 ppm groups. A number of non-neoplastic histopathological changes were observed, with the most significant being in the kidney. The only neoplastic change observed was in male rats and was an increase in interstitial cell adenomas of the testis considered to represent marked hyperplasia and not autonomous growth. The increased incidence was considered related to the unusually low frequency of testicular tumors in the control group. No increases in the incidence of neoplastic lesions were noted for female rats. In summary, the report allows the conclusion that there no adverse exposure related effects. Therefore, from the present report, a NOAEL of 5000 ppm IPA can be derived.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEC

12.47 mg/m³

Study duration:

subacute

Species:

rat

Repeated dose toxicity: inhalation - local effects

Link to relevant study records

Reference

Endpoint:

repeated dose toxicity: inhalation, other

Remarks:

combined repeated dose and carcinogenicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Propan-2-ol (Isopropyl alcohol) is both reagents used in the manufacture of IPETC/O-isopropyl ethylthiocarbamate. Therefore, Propan-2-ol (Isopropyl alcohol) need to be considered in the assessment of IPETC/O-isopropyl ethylthiocarbamate

Qualifier:

according to guideline

Guideline:

other: OECD 451

Deviations:

yes

Remarks:

Not monitoring food consumption

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague Dawley Inc. Indianapolis, IN
- Age at study initiation: 28-30 days old
- Weight at study initiation: 121.2-165 g (males) and 93.6 - 124.3 g (females) on the first day of exposure
- Fasting period before study: None
- Housing: 2 per cage in stainless steel, wire mesh cages
- Diet (e.g. ad libitum): Pelleted, certified AGWAY PROLAB animal diet rat 3000 ad libitum
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 3 weeks


ENVIRONMENTAL CONDITIONS
- Temperature : 17 - 26 °C
- Humidity (%): 40-70
- Air changes (per hr): Not reported
- Photoperiod (hrs dark / hrs light): 12-12

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: Not reported

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Inhalation chamber (Wahmann Manufacting company, Timonium, MD)
- System of generating particulates/aerosols: liquid isopropanol was metered from a container by piston pump
- Temperature in air chamber: 22 +/- 4 degrees
- Air flow rate: 1000 l/min for first month and 900 l/min thereafter
- Air change rate: 14 air changes/hr for first month and 12.5 air changes/hr thereafter
- Method of particle size determination: not reported
- Treatment of exhaust air: not reported


TEST ATMOSPHERE
- Brief description of analytical method used: liquid isopropanol was metered from a container by piston pump into a heated glass evaporator and the temperature of the evaporators was maintained at the lowest level to sufficiently vaporize the test substance.
- Samples taken from breathing zone: yes

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Each exposure chamber was analyzed for isopropanol twice each hour by flame ionization gas chromatography.

Duration of treatment / exposure:

at least 104 weeks

Frequency of treatment:

6 hours/day, 5 days/week

Remarks:

Doses / Concentrations:
0, 500, 2500, 5000 ppm
Basis:
nominal conc.

No. of animals per sex per dose:

65 sex/dose for the core group and 10 sex/dose for the interm sacrifice

Control animals:

yes, sham-exposed

Details on study design:

- Rationale for animal assignment (if not random): animals were assigned to 3 exposure groups and a control group using a sacrificed randomization procedure based on body weight
- Rationale for selecting satellite groups: 10 sex/group were sacrified in the middle of the study

Positive control:

None

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice a day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly for the first 14 weeks and then every other week after

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No data

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: No data

WATER CONSUMPTION: No data

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: prior to experiment, and during weeks 71, 80, 104, and 107
- Dose groups that were examined: all rats


HAEMATOLOGY: Yes
- Time schedule for collection of blood: 13 months, 19 months, and 25 months
- Anaesthetic used for blood collection: Yes (identity) methoxyflurane
- Animals fasted: No
- How many animals: 10 sex/dose level

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: week 57
- Animals fasted: No
- How many animals: 10 sex/dose group

URINALYSIS: Yes
- Time schedule for collection of urine: week 57, 59, 74, and 104
- Metabolism cages used for collection of urine: No
- Animals fasted: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Other examinations:

None

Statistics:

The data for the 3 treatment groups and the control group were compared with Levene's test for equality of variances, analysis of variance (ANOVA), and t-tests. The nonparmetric data were statistically evaluated with the Kruskal-Wallis test followed by the Mann-Whitney U-test. Mortality was analysed by life-table analyses. Incidence data were compared using Fishers exact test.

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:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

effects observed, treatment-related

Behaviour (functional findings):

no effects observed

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
- Mortality rates for males in the 0, 500, 2500, and 5000 ppm groups were 82, 83, 91, and 100%, respectively. For females, 54, 48, 55, and 69%. No significant differences were noted for male rats from 500 or 2500 groups or any female rats.
-In males and females exposed to 5000 ppm; hypoactivity, lack of a startle reflex, and narcosis were identified. In males and females exposed to 2500 ppm; hypoactivity, and a lack of a startle reflex were observed. No effects in 500 ppm group. During non-exposure periods in males 5000 ppm group emaciation and dehydration was observed. In males and females in 5000 ppm there was greater numbers of rats with urine stains and swollen periocular tissue (females only). Females in the 2500 ppm group also had increased incidence of urine stains.

BODY WEIGHT AND WEIGHT GAIN
-Decreased body weights were observed for male rats from the 5000 ppm group in the first and second weeks of exposure, and then increased and at the end of week 6 body weights were increased significantly over the control group. Increased body weights were also noted for male rats from the 2500 ppm group.
-Decreased body weights were observed for female rats from the 5000 ppm group in the first and second weeks of exposure, and then increased and at the end of week 5 body weights were increased significantly over the control group. Increased body weights were also noted for female rats from the 500 ppm group. At week 72, all female body weights were significantly increased when compared to the control group.

URINALYSIS
-In males in the 5000 ppm group, in weeks 57, 59, 74, and 104 decrease in osmolality and increase in total protein and total volume were reported.
-In females rats in the 5000 ppm group, a decrease in osmolality and an increase in total volume was reported. At week 74, total glucose excreted in the urine was increased for females in the 5000 ppm group.


ORGAN WEIGHTS
- At the interim sacrifice, absolute and relative kidney weights were increased for male rats in the 5000 ppm group. Relative liver weights were increased for male rats in the 2500 ppm group. Concentration-related increases in absolute and relative testes weight was reported for male rats in 5000 ppm group. In females, increases in absolute and relative lung weight for rats in the 5000 ppm was reported.
-At the terminal sacrifice, increase in relative liver weight was noted for male rats in 2500 ppm group. In females, an increase in absolute and relative liver and kidney weights were noted for the 5000 ppm group.


GROSS PATHOLOGY
- At the interim sacrifice, an increase in granular kidneys in male rats from the 2500 and 5000 ppm groups were noted
- At the terminal sacrifice, an increase in granular kidneys in male rats from the 2500 ppm group was noted. Increased frequencies of gross lesions for male rats that died included increase incidence of thickened stomachs, granular kidneys, and color change of the kidneys for animals in 2500 and 5000 ppm groups.
- For females that died before the end of the study, an increased incidence of thickened stomachs was noted for animals from the 5000 ppm group and granular kidneys were noted for animals from the 2500 and 5000 ppm groups.


HISTOPATHOLOGY: NON-NEOPLASTIC
- At the interim sacrifice, male rats from the 5000 ppm group had an increased frequency of testicular seminiferous tubule atrophy.
-Increased frequencies of kidney lesions were observed in male rats in the 2500 and 5000 dose groups that died during the study. Increased in the frequency of mineralization in the heart, aorta, vasculature, stomach, larynx, trachea, lungs, kidney, cornea, and testes was noted for male rats in the 2500 and 5000 ppm dose groups that died during the study. Additionally, basophilic cell foci in the liver, splenic hemosiderosis, rhinitis, and squamous metaplasisa of the respiratory epithelium in the nasal cavity were reported for male rats in the 5000 ppm group that died during the study.
-Increased severity of glomerulosclerosis was observered in female rats in the 5000 ppm group. Renal disease was also increased in female rats in the 5000 ppm group.
- For female rats that died during the study, increased frequencies of mineralization in the heart, aorta, vasculature, stomach, larynx, trachea, lungs and kidney. Increase in myocardial degeneration, atrial thrombosis, splenic hemosiderosis, ocular keratitis, inflammatory and metaplastic changes in the nasal cavity, squamous metaplasia of the respiratory epithelium and glandular ectasia in the gastric mucosa was also evident in females in the 5000 ppm group that died during the study.


HISTOPATHOLOGY: NEOPLASTIC (if applicable)
-Dose-related increase in interstitial cell adenomas of the testis in male rats at interim sacrifice, at the terminal sacrifice, and in male rats that died during the study.

Dose descriptor:

NOEL

Effect level:

500 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: for species specific toxic effects

Dose descriptor:

NOEL

Effect level:

5 000 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: for oncogenicity effects

Dose descriptor:

NOAEL

Effect level:

5 000 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: The report allows the conclusion that there are no substance specific adverse exposure related effects. A NOAEL of 5000 ppm can be derived.

Dose descriptor:

NOAEL

Effect level:

12.47 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Concentrations of 5000 ppm is equal to 12.47 mg/m³ (molecular mass of 60.10 g/mol for Propan-2-ol)

Critical effects observed:

not specified

Conclusions:

The no-observed-effect level (NOEL) for toxic effects for both rats and mice was 500 ppm. The NOEL for oncogenicity effects for both mice and rats was determined to be greater than 5000 ppm.Propan-2-ol (Isopropyl alcohol) is both reagents used in the manufacture of IPETC/ O-isopropyl ethylthiocarbamate. Therefore, Propan-2-ol (Isopropyl alcohol) need to be considered in the assessment of IPETC/O-isopropyl ethylthiocarbamate .

Executive summary:

The inhalation toxicity of IPA( isopropyl alcohol) has been assessed in a 104-week oncogenicity study in rats . This study was conducted according to OECD test guideline 451. IPA was administered by whole-body inhalation to groups of male and female Fischer 344 rats (75 rats/sex) for6 hours/day 5 days/weekfor at least 104 weeks at nominal concentrations of 0 (control), 500, 2500, or 5000 ppm (measure concentrations of0, 504, 2509, or 5031 ppm, respectively). Ten rats/sex/group were assigned to interim sacrifice at Week 73. Animals were monitored for clinical observations, body and organ weights, ophthalmology examinations, hematology, urinalysis and urine chemistry examinations, gross pathology and microscopic examinations. Exposure of rats to IPA vapour for 104 weeks produced clinical signs of toxicity (including hypoactivity, lack of startle reflex, and/or narcosis), changes in body weight, and urinalysis and urine chemistry indicative of kidney changes (decrease in osmolality and increase in total volume and/or protein) in the 2500 and 5000 ppm groups. At terminal sacrifice, increased absolute and relative kidney weights were noted in males at 2500 ppm and females at 5000 ppm. Macroscopic changes such as granular kidney were noted in males and females of 2500 and 5000 ppm groups. A number of non-neoplastic histopathological changes were observed, with the most significant being in the kidney. The only neoplastic change observed was in male rats and was an increase in interstitial cell adenomas of the testis considered to represent marked hyperplasia and not autonomous growth. The increased incidence was considered related to the unusually low frequency of testicular tumors in the control group. No increases in the incidence of neoplastic lesions were noted for female rats. In summary, the report allows the conclusion that there no adverse exposure related effects. Therefore, from the present report, a NOAEL of 5000 ppm IPA can be derived.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEC

12.47 mg/m³

Study duration:

subacute

Species:

rat

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

other: published data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Dithiocarbamates are related compounds toThionocarbamate.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)

Deviations:

yes

Remarks:

Data about the area covered by the test material and occlusion are not reported.

GLP compliance:

not specified

Limit test:

no

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Interfauna U.K. Ltd., Huntingdon, Cambridgeshire, England
- Age at study initiation: 10-12 weeks on arrival
- Weight at study initiation: fehlt noch
- five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg

Type of coverage:

not specified

Vehicle:

water

Details on exposure:

TEST SITE
- Area of exposure: no data

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with water
- Time after start of exposure: 6 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 100, 300, 1000 mg/kg bw/day
- For solids, paste formed: Yes. Powder was moistened with water

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

purity of ziram was analysed

Duration of treatment / exposure:

21 days

Frequency of treatment:

daily

Remarks:

Doses / Concentrations:
100, 300, 1000 mg/kg bw/day
Basis:
nominal per unit body weight

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

Ziram (purity 98.5%) was applied to the intact skin of groups of five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg, daily for 21 consecutive days at doses of 0, 100, 300, or 1000 mg/kg bw per day. The test substance was moistened with distilled water and maintained on the backs of the rabbits for 6 h each day, after which the dressings were removed and the treated skin washed with tap-water at 30-40°C and gently blotted dry. No dermal reaction to the treatment was observed at any dose. Significant losses in body weight or low body-weight gain and reduced food consumption were recorded for female rabbits receiving 1000 mg/kg bw. The number of lymphocytes was reduced in both males and females at 1000 mg/kg bw, and alanine and aspartate transaminase activities were increased at 300 and 1000 mg/kg bw. At the highest dose, significantly increased levels of bilirubin were found in females and of cholesterol in animals of each sex. The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Positive control:

no

Observations and examinations performed and frequency:

CLINICAL SIGNS
- Time schedule: once daily

MORTALITY
- Time schedule: once daily

DERMAL IRRITATION
- Time schedule for examinations: Prior to the first application and subsequent daily (erythema and eschar / oedema formation) .

BODY WEIGHT
- Time schedule for examinations: Prior to dosing and then once weekly.

FOOD CONSUMPTION
- Time schedule for examinations: Once weekly.

HAEMATOLOGY
- Time schedule for collection of blood: For all animals at Day 20. For specified animals procedure was repeated on Day 22.
- Animals fasted: Yes
- Parameters: haematocrit, erythrocyte count, haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration, platelet count, total leukocyte count, differential leukocyte count, cell morphology, thrombotest
CLINICAL CHEMISTRY
- Time schedule for collection of blood: For all animals at Day 20. For specified animals procedure was repeated on Day 22.
- Animals fasted: Yes
- Parameters: glucose, blood urea nitrogen, creatinine, total bilirubin, total cholesterol, alanine aminotransferase (GPT), aspartate aminotransferase (GOT), alkaline phosphatase, calcium, phosphorus, sodium, potassium, chloride, albumin, total protein, albumin/globulin ratio

Sacrifice and pathology:

ORGAN WEIGHTS
From all animals sacrificed at termination.
- Organs: adrenals, liver, kidneys, testes with epididymides/ovaries

GROSS AND HISTOPATHOLOGY
All animals were sacrificed at study termination and a gross pathological examination was performed.
- Histopathology: from all animals of the control and highest dose group
- Organs: abnormal tissue, skin (treated and untreated), kidneys, liver

Statistics:

All analyses were carried out separately for male and female.
The following tests were used for food and water consumption, bodyweight, relative organ weight and clinical pathology data:
- If the data consisted predominantly of one particular value (relative frequency of the mode exceeds 75%), the proportion of animals with values different from the mode was analysed by appropriate methods. Otherwise:
- Bartlett’s test was applied to test for heterogeneity of variance between treatments. Where significant (at the 1% level) heterogeneity was found, a logarithmic transformation was tried to see if a more stable variance structure could be obtained.
- If no significant heterogeneity was detected (or if a satisfactory transformation was found), a one-way analysis of variance was carried out. If significant heterogeneity of variance was present, and could not be removed by a transformation, the Kruskal-Wallis analysis of ranks was used.
- Analyses of variance were followed by a Student’s ‘t’ test and Williams’ test for a dose-related response, although only the one thought most appropriate for the response pattern observed has been reported. The Kruskal-Wallis analyses were followed by the non-parametric equivalents of the ‘t’ test and Williams’ test (Shirleys’ test).
Where appropriate for organ weight data, analysis of covariance was used in place of analysis of variance.

Clinical signs:

no effects observed

Dermal irritation:

no effects observed

Mortality:

no mortality observed

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):

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:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

BODY WEIGHT AND WEIGHT GAIN
Bodyweight losses or reduced bodyweight gain was observed in females dosed at 1000 mg/kg bw/day.

FOOD CONSUMPTION
Reduction was measured for females dosed at 1000 mg/kg bw/day in week 1. Food consumption was also reduced in the following weeks but did not achieve statistical significance.

HAEMATOLOGY
Significant lower lymphocyte counts for females dosed at 1000 mg/kg bw/day.

CLINICAL CHEMISTRY
Liver enzymes GOT and GPT were increased in females dosed at 1000 mg/kg bw/day and in case of GOT also at 300 mg/kg bw/day.
Increased levels of bilirubin amongst females and cholesterol amongst both sexes dosed at 1000 mg/kg bw/day were also observed.

GROSS PATHOLOGY
Increased incidence of irregular cortical scarring of the kidney in all groups was not considered to be treatment-related.

Dose descriptor:

NOAEL

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Dose descriptor:

NOAEL

Effect level:

144.43 mg/kg bw/day (nominal)

Based on:

test mat.

Remarks:

Isopropyl Ethyl Thionocarbamate (IPETC)

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

not specified

On a molecular weight scaled basis, the NOAELwould be 155.2 mg/kg bw (300x 147.24) /305.84 = 144.43 mg/kg bw

Conclusions:

On a molecular weight scaled basis, the NOAEL would be 144.43 mg/kg bw (300x 147.24) /305.84 = 144.43 mg/kg bw for Isopropyl Ethyl Thionocarbamate (IPETC)
The NOAEL was 144.43 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin
Dithiocarbamates are related compounds to Thionocarbamate.

Executive summary:

Ziram (purity 98.5%) was applied to the intact skin of groups of five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg, daily for 21 consecutive days at doses of 0, 100, 300, or 1000 mg/kg bw per day. The test substance was moistened with distilled water and maintained on the backs of the rabbits for 6 h each day, after which the dressings were removed and the treated skin washed with tap-water at 30-40°C and gently blotted dry. No dermal reaction to the treatment was observed at any dose. Significant losses in body weight or low body-weight gain and reduced food consumption were recorded for female rabbits receiving 1000 mg/kg bw. The number of lymphocytes was reduced in both males and females at 1000 mg/kg bw, and alanine and aspartate transaminase activities were increased at 300 and 1000 mg/kg bw. At the highest dose, significantly increased levels of bilirubin were found in females and of cholesterol in animals of each sex. The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

144.43 mg/kg bw/day

Study duration:

subacute

Species:

rabbit

Repeated dose toxicity: dermal - local effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

other: published data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Dithiocarbamates are related compounds toThionocarbamate.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)

Deviations:

yes

Remarks:

Data about the area covered by the test material and occlusion are not reported.

GLP compliance:

not specified

Limit test:

no

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Interfauna U.K. Ltd., Huntingdon, Cambridgeshire, England
- Age at study initiation: 10-12 weeks on arrival
- Weight at study initiation: fehlt noch
- five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg

Type of coverage:

not specified

Vehicle:

water

Details on exposure:

TEST SITE
- Area of exposure: no data

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with water
- Time after start of exposure: 6 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 100, 300, 1000 mg/kg bw/day
- For solids, paste formed: Yes. Powder was moistened with water

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

purity of ziram was analysed

Duration of treatment / exposure:

21 days

Frequency of treatment:

daily

Remarks:

Doses / Concentrations:
100, 300, 1000 mg/kg bw/day
Basis:
nominal per unit body weight

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

Ziram (purity 98.5%) was applied to the intact skin of groups of five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg, daily for 21 consecutive days at doses of 0, 100, 300, or 1000 mg/kg bw per day. The test substance was moistened with distilled water and maintained on the backs of the rabbits for 6 h each day, after which the dressings were removed and the treated skin washed with tap-water at 30-40°C and gently blotted dry. No dermal reaction to the treatment was observed at any dose. Significant losses in body weight or low body-weight gain and reduced food consumption were recorded for female rabbits receiving 1000 mg/kg bw. The number of lymphocytes was reduced in both males and females at 1000 mg/kg bw, and alanine and aspartate transaminase activities were increased at 300 and 1000 mg/kg bw. At the highest dose, significantly increased levels of bilirubin were found in females and of cholesterol in animals of each sex. The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Positive control:

no

Observations and examinations performed and frequency:

CLINICAL SIGNS
- Time schedule: once daily

MORTALITY
- Time schedule: once daily

DERMAL IRRITATION
- Time schedule for examinations: Prior to the first application and subsequent daily (erythema and eschar / oedema formation) .

BODY WEIGHT
- Time schedule for examinations: Prior to dosing and then once weekly.

FOOD CONSUMPTION
- Time schedule for examinations: Once weekly.

HAEMATOLOGY
- Time schedule for collection of blood: For all animals at Day 20. For specified animals procedure was repeated on Day 22.
- Animals fasted: Yes
- Parameters: haematocrit, erythrocyte count, haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration, platelet count, total leukocyte count, differential leukocyte count, cell morphology, thrombotest
CLINICAL CHEMISTRY
- Time schedule for collection of blood: For all animals at Day 20. For specified animals procedure was repeated on Day 22.
- Animals fasted: Yes
- Parameters: glucose, blood urea nitrogen, creatinine, total bilirubin, total cholesterol, alanine aminotransferase (GPT), aspartate aminotransferase (GOT), alkaline phosphatase, calcium, phosphorus, sodium, potassium, chloride, albumin, total protein, albumin/globulin ratio

Sacrifice and pathology:

ORGAN WEIGHTS
From all animals sacrificed at termination.
- Organs: adrenals, liver, kidneys, testes with epididymides/ovaries

GROSS AND HISTOPATHOLOGY
All animals were sacrificed at study termination and a gross pathological examination was performed.
- Histopathology: from all animals of the control and highest dose group
- Organs: abnormal tissue, skin (treated and untreated), kidneys, liver

Statistics:

All analyses were carried out separately for male and female.
The following tests were used for food and water consumption, bodyweight, relative organ weight and clinical pathology data:
- If the data consisted predominantly of one particular value (relative frequency of the mode exceeds 75%), the proportion of animals with values different from the mode was analysed by appropriate methods. Otherwise:
- Bartlett’s test was applied to test for heterogeneity of variance between treatments. Where significant (at the 1% level) heterogeneity was found, a logarithmic transformation was tried to see if a more stable variance structure could be obtained.
- If no significant heterogeneity was detected (or if a satisfactory transformation was found), a one-way analysis of variance was carried out. If significant heterogeneity of variance was present, and could not be removed by a transformation, the Kruskal-Wallis analysis of ranks was used.
- Analyses of variance were followed by a Student’s ‘t’ test and Williams’ test for a dose-related response, although only the one thought most appropriate for the response pattern observed has been reported. The Kruskal-Wallis analyses were followed by the non-parametric equivalents of the ‘t’ test and Williams’ test (Shirleys’ test).
Where appropriate for organ weight data, analysis of covariance was used in place of analysis of variance.

Clinical signs:

no effects observed

Dermal irritation:

no effects observed

Mortality:

no mortality observed

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):

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:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

BODY WEIGHT AND WEIGHT GAIN
Bodyweight losses or reduced bodyweight gain was observed in females dosed at 1000 mg/kg bw/day.

FOOD CONSUMPTION
Reduction was measured for females dosed at 1000 mg/kg bw/day in week 1. Food consumption was also reduced in the following weeks but did not achieve statistical significance.

HAEMATOLOGY
Significant lower lymphocyte counts for females dosed at 1000 mg/kg bw/day.

CLINICAL CHEMISTRY
Liver enzymes GOT and GPT were increased in females dosed at 1000 mg/kg bw/day and in case of GOT also at 300 mg/kg bw/day.
Increased levels of bilirubin amongst females and cholesterol amongst both sexes dosed at 1000 mg/kg bw/day were also observed.

GROSS PATHOLOGY
Increased incidence of irregular cortical scarring of the kidney in all groups was not considered to be treatment-related.

Dose descriptor:

NOAEL

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Dose descriptor:

NOAEL

Effect level:

144.43 mg/kg bw/day (nominal)

Based on:

test mat.

Remarks:

Isopropyl Ethyl Thionocarbamate (IPETC)

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

not specified

On a molecular weight scaled basis, the NOAELwould be 155.2 mg/kg bw (300x 147.24) /305.84 = 144.43 mg/kg bw

Conclusions:

On a molecular weight scaled basis, the NOAEL would be 144.43 mg/kg bw (300x 147.24) /305.84 = 144.43 mg/kg bw for Isopropyl Ethyl Thionocarbamate (IPETC)
The NOAEL was 144.43 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin
Dithiocarbamates are related compounds to Thionocarbamate.

Executive summary:

Ziram (purity 98.5%) was applied to the intact skin of groups of five male and five female New Zealand white rabbits, weighing 2.2-2.6 kg, daily for 21 consecutive days at doses of 0, 100, 300, or 1000 mg/kg bw per day. The test substance was moistened with distilled water and maintained on the backs of the rabbits for 6 h each day, after which the dressings were removed and the treated skin washed with tap-water at 30-40°C and gently blotted dry. No dermal reaction to the treatment was observed at any dose. Significant losses in body weight or low body-weight gain and reduced food consumption were recorded for female rabbits receiving 1000 mg/kg bw. The number of lymphocytes was reduced in both males and females at 1000 mg/kg bw, and alanine and aspartate transaminase activities were increased at 300 and 1000 mg/kg bw. At the highest dose, significantly increased levels of bilirubin were found in females and of cholesterol in animals of each sex. The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

2.73 mg/cm²

Study duration:

subacute

Species:

rabbit

Additional information

Oral repeated dose toxicity

 NOAEL of 125 mg/kg bw/day was established based on no effects observed forButan-1-ol (Butyl alcohol)as a main constituent of IPETC/ O-isopropyl ethylthiocarbamate . LOAEL of 500 mg/kg bw/day was established based onclinical signs of SNC depression (ataxia and hypoactivity).

In the (Q)SAR study, NOAEL for Repeated dose oral toxicity was 250 mg/kg bw/day (No adverse effects on the highest dose tested) for Isopropyl Ethyl Thionocarbamate (IPETC) .This HESS QSAR grouping method contains simple categories for Repeated dose oral toxicity.This method is relevant for Repeated dose oral toxicity endpoints in mammals. The database include a set of 91 chemicals that have been evaluated for their repeated dose oral toxicity potential.

Inhalation repeated dose toxicity

 

The results of the study (Burleigh-Flayer H, Garman R, Neptun D, Bevan C, Gardiner T, Kapp R, Tyler T & Wright G 1997) indicate that Propan-2-ol (Isopropyl alcohol) as a main constituent of IPETC/ O-isopropyl ethylthiocarbamate has not an adverse effect at concentration of 5000 ppm on kidneys in rats. Macroscopic changes such as granular kidney were noted in males and females of 2500 and 5000 ppm groups. A number of non-neoplastic histopathological changes were observed, with the most significant being in the kidney. The only neoplastic change observed was in male rats and was an increase in interstitial cell adenomas of the testis considered to represent marked hyperplasia and not autonomous growth.

NOAEL of 5000 ppm can be derived. Concentrations of 5000 ppm is equal to 12.47 mg/m³ (molecular mass of 60.10 g/mol for Propan-2-ol)

Dermal repeated dose toxicity

 

Dithiocarbamates are related compounds to Thionocarbamate. The NOAEL was 300 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin and cholesterol levels at 1000 mg/kg bw per day for Dithiocarbamates

On a molecular weight scaled basis, the NOAEL would be 144.43 mg/kg bw (300x 147.24) /305.84 = 144.43 mg/kg bw for Isopropyl Ethyl Thionocarbamate (IPETC) .

The NOAEL was 144.43 mg/kg bw per day, on the basis of decreased body weight, body-weight gain, food consumption, and number of lymphocytes and increased bilirubin

Justification for selection of repeated dose toxicity dermal - local effects endpoint:
The generic modification from the NOAELtest (in mg/kg of body weight) to NOAELmodified (in mg/cm2/day) will be
NOAELin mg/cm2 = ((dose in mg/kg bw)x (average animal weight in kg)) / Treated surface in cm2)

NOAELtest* 2.4/127= NOAELmodified

The highest dose not causing irritation/corrosion was 144.43 mg/kg bw in twenty-one day dermal toxicity study in rabbits of Edwards et al.,1989,
the modified dose descriptor would be
NOAELmodified =144.43 mg/kg*2.4 kg/127cm2=2.73 mg/cm2

Repeated dose toxicity: via oral route - systemic effects (target organ) cardiovascular / hematological: other; other: all gross lesions and masses

Repeated dose toxicity: inhalation - systemic effects (target organ) digestive: liver; other: all gross lesions and masses

Repeated dose toxicity: dermal - systemic effects (target organ) other: skin

Justification for classification or non-classification

 

Based on the hazard assessment of IPETC/O-isopropyl ethylthiocarbamate in section 2.1 and 2.2. in IUCLID 6., available data for the substance and following the “Guidance onInformation Requirement and Chemical Safety Assessment R.8. Characterisation of dose [concentration]- response for human health”, according to the EU’s list of dangerous substances (OJEC No L200/130.7.99) and according to the criteria described in Directive 67/548 and in the CLP Regulation:

 

Directive 67/548

Repeated dose toxicity R33 Danger of cumulative effects. T; R48/23 Toxic; Toxic: danger of serious damage to health by prolonged exposure through inhalation. T; R48/23/24 Toxic; Toxic: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin. T; R48/23/24/25 Toxic; Toxic: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed. T; R48/23/25 Toxic; Toxic: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed. T; R48/24 Toxic; Toxic: danger of serious damage to health by prolonged exposure in contact with skin. T; R48/24/25 Toxic; Toxic: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed. T; R48/25 Toxic; Toxic: danger of serious damage to health by prolonged exposure if swallowed. Xn; R48/20 Harmful; Harmful: danger of serious damage to health by prolonged exposure through inhalation. Xn; R48/20/21 Harmful; Harmful: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin. Xn; R48/20/21/22 Harmful; Harmful: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed. Xn; R48/20/22 Harmful; Harmful: danger of serious damage to health by prolonged exposure through inhalation and if swallowed. Xn; R48/21 Harmful; Harmful: danger of serious damage to health by prolonged exposure in contact with skin. Xn; R48/21/22 Harmful; Harmful: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed. Xn; R48/22 Harmful; Harmful: danger of serious damage to health by prolonged exposure if swallowed.

CLP

Repeated dose toxicity STOT Rep. Exp. 1 STOT Rep. Exp. 2 H372: Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. H373: May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.

 

 

It is concluded that the substance IPETC/ O-isopropyl ethylthiocarbamate and n-butanol and propan-2-ol does not meet the criteria to be classified for human health hazards for Repeated dose toxicity