2,2-bis[(allyloxy)methyl]butyl (3-{[({2,2-bis[(allyloxy)methyl]butoxy}carbonyl)amino]methyl}-3,5,5-trimethylcyclohexyl)carbamate

Endpoint summary

Description of key information

Repeated dose toxicity: oral (28 days)

Under the conditions of the study, the NOAEL has been determined to be greater than 1000 mg/kg bw.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Section 4 of the Guidelines for the Testing of Chemicals: Health Effects (ministry of environmental protection of People's Republic of China).

Deviations:

no

GLP compliance:

not specified

Remarks:

Not specified

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Remarks:

clean grade

Details on species / strain selection:

The rat was the preferred rodent species for this study and the Sprague-Dawley strain was chosen due to its sensitivity against the known chemicals and uniformity in genetic properties.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 133 to 161 g
- Housing: There were two animals in one polycarbonate box, and the boxes were changed twice every week. The boxes were disinfected with an autoclave.
- Diet: powdered diet
- Water: The drinking water was sterilised, and rats were allowed to drink freely for drinking water during the experimental period.
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 20 to 25°C
- Humidity: 40 to 70%
- Photoperiod: 12 hrs dark / 12 hrs light

Route of administration:

other: metallic stomach catheter

Details on route of administration:

The test substance was administered orally to animals once daily by a metallic stomach catheter.

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
A prescribed amount of the test material was weighed and then diluted with corn oil to designed concentrations.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

28 days

Frequency of treatment:

Once daily

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Dose / conc.:

250 mg/kg bw/day (nominal)

Dose / conc.:

62.5 mg/kg bw/day (nominal)

No. of animals per sex per dose:

10 animals per sex per dose

Control animals:

yes, concurrent no treatment

Details on study design:

- Dose selection rationale: Groups of 1000, 250, 62.5 and 0 mg/kg-bw (high, middle, low and control group) were set up according to the result of the acute oral toxicity study.
- Animal assignment: Before the test, animals were assigned to 6 groups randomly, 10 rats per sex in each group.

Observations and examinations performed and frequency:

DETAILED CLINICAL OBSERVATIONS: Yes
Toxicological signs were recorded including the time of onset, degree and duration. Abnormalities were recorded in detail.

BODY WEIGHT: Yes
- The body weight of the rats were recorded weekly

FOOD EFFICIENCY: Yes

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- At the end of experiment, blood samples from all animals were collected for analysis of red blood cell (RBC), white blood cell (WBC), leukocyte differential count (the rate of neutrocyte (NEU%), the rate of lymphocyte (LYM%), the rate of monocyte (MONO%), the rate of basophils (BASO%), the rate of eosinophil (EOS%), platelet (PLT) counts, plasma prothrombin time (PT(INR)), activated partial thromboplatin (APTT) and hemoglobin (Hb) content.

CLINICAL CHEMISTRY: Yes
- At the end of experiment, blood samples were collected to analyse alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin total (TBIL), protein total (TP), albumin (ALB), blood urea nitrogen (BUN), creatinine (CREA), cholesterol total (CHOL), glucose (GLU), cholinesterase (CHE), Na, K, Cl, Ca and P.

URINALYSIS: Yes
- At the end of experiment, urine samples from all of the animals were collected to analyse the specific gravity, colour, pH, protein contents, crypt-blood and sugar concentrations.

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

OTHER:
Brain, heart, lung, liver, spleen, kidney, adrenal gland, testis or ovary and thymus were weighed immediately after collection.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
- All the animals were subjected to a full gross necropsy and macroscopically observed in detail at the end of experiment. All tissues collected were fixed with 10% formaldehyde for histological examination.

HISTOPATHOLOGY: Yes
- The following tissues were collected for histological examination in control and high groups: brain, heart, lung, liver, spleen, kidney, adrenal gland, testis or ovary, nervus ischiadicus, cervical, spinal cord, thymus, thyroid, pancreas, stomach, duodenum, jejunum, ileum, colon, rectum, mesenteric lymph node, prostate, epididymis, urinary bladder and uterus.

Statistics:

Data was analysed by ANOVA, and the additional high and control dosage group were analysed by t-test using SPSS10.0.

Clinical signs:

no effects observed

Description (incidence and severity):

No abnormalities were observed.

Mortality:

no mortality observed

Description (incidence):

There was no mortality during the study.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

No obvious effects were observed.

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

no effects observed

Description (incidence and severity):

No obvious effects were observed.

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

For females, the rate of BASO was increasing in both high and middle groups (p<0.05), but it had no clinical meaning.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

For females, ALT was decreasing in the high group (p<0.05) and for males CREA was descending in the high group compared with the control group (p<0.05). The results had no clinical meanings.

Urinalysis findings:

no effects observed

Description (incidence and severity):

There was no abnormality of the specific gravity, colour, sugar, pH, crypt-blood and protein.

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

For females, the weight of the thymus in the additional high group was decreasing (p<0.05) compared to the additional control group, but it had no clinical meaning.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Gross necropsy showed that there was no overt abnormality.

In the female control group, no abnormality was found in any of the organs.

In the male control group, light-grade fatty degeneration of liver cells was observed in one animal, middle-grade infiltration of inflammatory cell around pulmonary vascular was observed in one animal, light-grade infiltration of inflammatory cell in-between the prostate was observed in two animals and middle-grade infiltration was observed in one animal.

In the female, high dose group, light-grade infiltration of inflammatory cell in-between the portal area of liver was observed in one animal, local cerebral lung consolidation and middle-grade infiltration of inflammatory cell was observed in one animal, local cerebral light-grade hyperaemia in alveolar wall was observed in one animal, light-grade infiltration of inflammatory cell in-between interstitial of the urinary bladder was observed in one animal and middle-grade infiltration was observed in one animal

In the male high dose group, light-grade infiltration of inflammatory cell in-between the portal area of liver was observed in one animal, light fatty degeneration of liver cells was observed in three animals, light-grade degeneration of bladder epithelium was observed in one animal, light-grade infiltration of inflammatory cell in-between the epididymis was observed in two animals, light-grade infiltration of inflammatory cell in-between the prostate was observed in one animal and light infiltration of inflammatory cell in-between the prostate, accompanied with middle epithelial degeneration, necrosis and light-grade fibrous connective tissue hyperplasia was observed in one animal.

In the additional female control group, no abnormality was found in any of the organs.

In the additional male control group, light fatty degeneration of liver cells was observed in one animal, local cerebral alveolar filled with inflammatory and red cells found was observed in one animal, light-grade infiltration of inflammatory cell in-between the prostate was observed in one animal and middle-grade infiltration of inflammatory cell in-between the prostate was observed in two animals.

In the additional female high dose group, light-grade infiltration of inflammatory cell in-between the portal area of liver was observed in one animal and light-grade infiltration of inflammatory cell in-between lamina porpria mucosae of ladder was observed in one animal.

In the additional, male high dose group, light fatty degeneration of liver cells was observed in two animals, light-grade infiltration of inflammatory cell in-between the portal area of liver was observed in one animal, middle-grade hyperaemia and thickening of alveolar wall was observed in one animal, middle-grade infiltration of inflammatory cell in-between the prostate was observed in one animal and light-grade infiltration of inflammatory cell in-between the prostate was observed in four animals.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Key result

Dose descriptor:

NOAEL

Effect level:

> 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food efficiency

gross pathology

haematology

mortality

organ weights and organ / body weight ratios

urinalysis

Critical effects observed:

not specified

Conclusions:

Under the conditions of the study, the NOAEL for the test material has been determined to be greater than 1000 mg/kg bw.

Executive summary:

The repeat dose oral toxicity of the test material to rats was determined in accordance with Section 4 of the Guidelines for the Testing of Chemicals: Health Effects (ministry of environmental protection of People's Republic of China), in a 28 day oral study. Ten animals per sex were dosed with test material (1000, 250, 62.5 and 0 mg/kg bw) once daily for 28 days via a stomach catheter. Concentrations were selected according to the results of the acute oral toxicity study. To observe the reversibility and delayed effects, an additional high dosage group (1000 mg/kg bw) and an additional control group (0 mg/kg bw) were applied and observed for another 14 days. During the study, body weight and food consumption were recorded weekly and overt signs of toxicity (including quality of hair, general condition of eyes, mouth, teeth, nose and ears, posture, gait, behaviour or activity, character of excreta, etc.) were observed daily. At the end of the study, urine and blood samples were collected before the rats were sacrificed and organs were subsequently taken for pathological examination. The data were statistically analysed by ANOVA between groups and the t-test was used for the additional groups respectively using SPSS 10.0.

No abnormal clinical signs and no mortality was observed during treatment. No significant changes was exhibited in body weight and total food efficiency. Compared with the control group, no significant difference was observed in organ to body weight ratios, haematology analysis and routine urinary analysis. Gross necropsy and pathological detection indicated that no significant changes were exhibited in any of the groups. Compared with the additional control group, no significant difference was observed in the additional high groups for every index measured. Under the conditions of the study, the NOAEL was determined to be greater than 1000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

One study is available. The study was performed in accordance with standardised guidelines but not under GLP conditions and was assigned a reliability score of 2 in line with the principles for assessing data quality as defined by Klimisch et al. (1997).

Additional information

Repeated dose toxicity: oral (28 days)

The repeat dose toxicity of the test material to rats was determined in accordance with Section 4 of the Guidelines for the Testing of Chemicals: Health Effects (ministry of environmental protection of People's Republic of China), in a 28 day oral study. Ten animals per sex were dosed with test material (1000, 250, 62.5 and 0 mg/kg bw) once daily for 28 days via a stomach catheter. Concentrations were selected according to the results of the acute oral toxicity study.To observe the reversibility and delayed effects, an additional high dosage group (1000 mg/kg bw) and an additional control group (0 mg/kg bw) were applied and observed for another 14 days. During the study, body weight and food consumption were recorded weekly and overt signs of toxicity (including quality of hair, general condition of eyes, mouth, teeth, nose and ears, posture, gait, behaviour or activity, character of excreta, etc.) were observed daily. At the end of the study, urine and blood samples were collected before the rats were sacrificed and organs were subsequently taken for pathological examination. The data were statistically analysed by ANOVA between groups and the t-test was used for the additional groups respectively using SPSS 10.0.

No abnormal clinical signs and no mortality was observed during treatment. No significant changes was exhibited in body weight and total food efficiency. Compared with the control group, no significant difference was observed in organ to body weight ratios, haematology analysis and routine urinary analysis. Gross necropsy and pathological detection indicated that no significant changes were exhibited in any of the groups. Compared with the additional control group, no significant difference was observed in the additional high groups for every index measured. Under the conditions of the study, the NOAEL was determined to be greater than 1000 mg/kg bw.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No 1272/2008, it is considered that the substance does not require classification with respect to repeated dose toxicity on the basis of the effects seen.