4-(1-oxo-2-propenyl)-morpholine

Endpoint summary

Description of key information

Oral:
A 28-day repeated dose toxicity study in Rats by Oral Gavage Administration was performed according to EC B.7 / OECD 407. The only treatment-related finding in the study was an adaptive liver change for high dosage group females at 50 mg/kg/day. The NOAEL was determined to be 50 mg/kg bw/day.
A 13-week Toxicity and Reproductive Screening Study in Rats by Oral Gavage Administration was conducted based OECD 408 and OECD 422. Based on the findings of this study the no-effect-level for general systemic toxic is considered to be 20 mg/kg/day and no-effect-level for neurobehavioral toxicity is 75 mg/kg/day. Other than lower bodyweight gain, particularly towards the end of the treatment period, treatment of test item at 75 mg/kg/day for 13 weeks was generally well tolerated by both male and female rats. Thus, the NOAEL should be > 75 mg/kg/day.

Inhalation:
Exposure of rats to the substance at daily doses of 0.0124, 0.0297 and 0.1238 mg/L for 5 days per week for 13 weeks, produced efects on bodyweight gain, food consumption and white blood cell parameters.
In addition changes consistent with local irritation were seen in the nasal turbinates of rats exposed to the substance. Minimal focal seminiferous tubular atrophy was evident in males at all exposure levels.
A no - observable efect level (NOEL) was not established in this study.

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 17 March to 05 August 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Specific details on test material used for the study:

Batch number: 60513F07
Purity: >99.5%

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles rive UK Ltd, England
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 28 days
- Weight at study initiation: 72 to 87 g
- Fasting period before study:
- Housing: initially cased in groups of 3 or 5 according to sex in metal cages with wire mesh floors
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16.5 - 21.5°C
- Humidity (%): 24 - 63%
- Air changes (per hr): 19 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours artificial light in each 24 hours period

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
The test substance was initially prepared in a suitable vehicle (distilled water). A series of formulations was prepared by serial dilution of the high dose level.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The chemical stability of test substance formulations was assessed prior to the start of treatment and was found to be satisfactory for 7 days when stored at 4°C in the dark and for 3 hours at ambient temperature.
Concentration analyses of formulations prepared for administration on day 1 were also performed.

Duration of treatment / exposure:

28 days

Frequency of treatment:

once daily

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

No. of animals per sex per dose:

5 males and 5 females

Control animals:

yes, concurrent vehicle

Observations and examinations performed and frequency:

CLINICAL SIGN OBSERVATIONS: Yes
- Time schedule: all animals were observed six times on day 1 and three times daily thereafter for signs of ill health, behavioural changes or toxicosis.

BODY WEIGHT: Yes
- Time schedule for examinations: all rats were weighed prior to dosing on day 1 and subsequently at weekly intervals throught the study.

FOOD CONSUMPTION: Yes
- Time schedule: the quantity of food consumed in each cage was measured at weekly intervals throughout the study.

WATER CONSUMPTION: Yes
- Time schedule for examinations: daily monitoring by visual appraisal was maintained throughout the dosing period.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: prior to termination at week 4
- Anaesthetic used for blood collection: Yes, light ether
- Animals fasted: Yes, overnight prior to collection
- How many animals: all 40 animals
- Parameters examined:
Packed cell volume, Haemoglobin, Red blood cell count, Platelet count, Total while blood cell count; Thrombotest, Different white blood cell count: Neutrophils, Lymphocytes, Eosinophils, Basophils, Monocytes; Polychromasia, Hypochromasia, Anisocytosis, Rouleaux formation.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: prior to termination at week 4
- Animals fasted: Yes, overnight prior to collection
- How many animals: all 40 animals
- Parameters examined:
Glucose, Total protein, Albumin, Globulin, Albumin/Globulin ratio, Urea nitrogen, Creatinine, Alkaline phosphatase, Glutamic-pyruvic transaminase, Glutamic-oxaloacetic transaminase, Total bilirubin, Sodium, Potassium, Calcium, Inorganic phosphorus, Chloride, Cholesterol

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
The macroscopic appearance of the tissues of all rats was recorded and samples of the following tissues were preserved in 10% buffered formalin:
adrenals, aorta, brain, caecum, colon, duodenum, eyes, femur, head, heart, ileum, jejunum, kidneys, larynx, liver, lungs, lymph nodes, mammary glands, oesophagus, ovaries, pancreas, pharynx, pituitary, prostate, rectum, salivary gland, sciatic nerve, seminal vesicles, skeletal muscle, skin, spleen, sternum, stomach, testes including epididymis, thymus, thyroid, tongue, trachea, urinary bladder, uterus, vagina

HISTOPATHOLOGY: Yes
Fixed tissue samples required for microscopic examination were prepared by embedding in paraffin wax, sections were cut at 4 um and stained with haematoxylin and eosin.
Microscopic examination of prepared slides were carried out for all rats of control group and high dosage group killed on day 29.
Examinations were extended following documented approval from the sponsor, to include the liver (female) of the intermediate and low dosage groups following observations of treatment-related change for animals of high dosage group.

Other examinations:

Organ weight:
The following organs from each animal were dissected free of fat and weighed:
adrenals, brain, kidneys, liver, ovaries, spleen, testes

Statistics:

All statistical analsyses were carried out separately for males and females using individual animal as basic experiment unit.
The following sequence of statistical tests was used for bodyweight gains, 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 values different from the mode was analysed by Fisher ’ s exact test ( Fisher 1950) folowed by Mantel ’ s test for a trend in proportions (Mantel 1963). Otherwise:
Bartlett ' s test (Bartlet 1937) was applied to test for heterogeneity of variance between treatments. If significant heterogeneity was found at the 1% level, 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 followed by Williams ’ test ( Williams 1971/2) for a dose - related response.
Where significant heterogeneity of variance was present and could not be removed by a logarithmic transformation , the Kruskal - Wallis analysis of ranks (Kruskal and Wallis 1952/3) was used. This analysis was followed by the non - parametric equivalent of Williams ’ test ( Shirley ’ s test ( Shirley 1977)).
Covariate analysis of organ weight data (with final bodyweight as covariate) was also performed using adjusted weights for organs where a correlation between organ weight and bodyweight was established at the 10% level of significance (Angervall and Carlstrom 1963).
Significant differences between control animals and those treated with test substance were expressed at the 5%(* P <0.05) or 1%(** P <0.01) level .

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

A small slightly reddened graze was noted on left shoulder of one female rat receiving 15 mg/kg/day from days 13 to 18.

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

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

no effects observed

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no statistically significant differences from control in any of the haematological
parameters measured that were considered to be related to treatment .
Statistically significantly higher than control total white blood cell count was recorded for male rats receiving 15 or 50 mg/kg/day. There was wide variation in individual values and overlap between the groups , this difference from control was not considered to be related to treatment .

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no statistically significant differences from control in any of the biochemical parameters
measured that were considered to be related to treatment at this stage .
Total protein was statistically significntly lower than for control for female rats treated at
50 mg/kg/day. Globulin was also lower than control for these rats and also for male rats treated at 50 or 15 mg/kg/day with consequently higher than control A/G ratio for all treated groups of rats . These differences from control were all smal in magnitude and there was no dosage - relationship . A treatment - related effect on protein was considered unlikely .
Minor differences from control in sodium (males at 50 mg/kg/day and females at 50 or
15 mg/kg/day), potassium and calcium (females at 50 mg/kg/day) were recorded. These small differences were considered to be chance occurrences and not an effect of treatment .

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Statistically significantly higher than control liver weight was recorded for female rats receiving
50 mg/kg/day.
There were по other statistically significant differences from control in any of the organ weights .

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Liver - Minimal centrilobular hepatocyte enlargement was seen in 2/5 female rats receiving
50 mg/kg/day. This correlates to the increased liver weights recorded for this dose group . No changes were seen in the liver of female rats receiving 4.5 mg/kg/day or 15 mg/kg/day or in any male rats from any of the dose groups .

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

gross pathology

histopathology: non-neoplastic

Critical effects observed:

yes

Lowest effective dose / conc.:

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

System:

hepatobiliary

Organ:

liver

Treatment related:

yes

Dose response relationship:

not specified

Relevant for humans:

not specified

Conclusions:

The only treatment-related finding in the study was an adaptive liver change for high dosage group females, 50 mg/kg/day was considered to represent the NOAEL in the rat for the substance, 15 mg/kg/day represents the NOEL.

Executive summary:

This study is performed to assess the systemic toxicity of the substance to the rat, according to OECD Guideline 407 under GLP.

The substance was administered to groups of rats for 28 days at dosage levels of 50, 15 and 4.5 mg/kg/day. Control animals received the vehicle, distilled water, alone.
The target organ for female rats of the high dosage group was the liver. Minimal centrilobular hepatocyte enlargement was seen microscopically with an associated increase in liver weight. This liver finding was considered to be adaptive and related to metabolism of the test substance. A similar effect was not seen in male rats of the high dosage group. There were no other treatment - related effects and the rats were clinically normal. Therefore this high dosage was considered to represent the no - observed - adverse - effect level (NOAEL) for the substance in the rat.
There were no treatment － related effects seen at the intermediate dosage level and therefore 15 mg/kg/day was considered to represent the no - observed effect level (NOEL) in the rat.

Reference 2

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2000-08-23 to 2001-03-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1998

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Version / remarks:

1996

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.6200 (neurotoxicity screening battery)

Version / remarks:

1998

Deviations:

no

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

Lot No.: 0600605-P
Purity: 99.50%

Species:

rat

Strain:

other: CD

Details on species / strain selection:

The rat was chosen because of its acceptance as a predictor of toxic change in man and the requirement for a rodent species by regulatory agencies. The CD strain was used because of the historical control data available in this laboratory for the general toxicity, neurobehavioral and reproductive parameters recorded in this study.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Limited
- Females (if applicable) nulliparous and non-pregnant: not specified
- Age at study initiation: 30 ± 1 days
- Weight at study initiation: Males: 119 to 185 g; Females: 131 to 174 g
- Housing: housed (TR18 cages) in groups of five of the same sex, unless reduced by mortality or isolation. TR18 cages were obtained from Arrowmight Biosciences, Hereford and consisted of stainless steel bodies with lids and floors of stainless steel grid. These cages were suspended in batteries over trays lined with absorbent paper that was changed at appropriate intervals.
- Diet: An expanded rodent diet, Rat and Mouse No. 1 Maintenance Diet, ad libitum
- Water: Water, taken from the public supply was freely available via polyethylene or polycarbonate bottles fitted with sipper tubes.
- Acclimation period: 9 days

DETAILS OF FOOD AND WATER QUALITY:
Both diet suppliers provided a Certificate of Analysis with every batch of diet. Both diets contained no added antibiotic or other chemotherapeutic or prophylactic agent.
The quality of the water supply is governed by regulations published by the Department of the Environment. Certificates of analysis were routinely received from the supplier.
No contaminants were reasonably expected to be present in water, diet or bedding at levels known to be capable of interfering with the progress or outcome of this study. No other specific contaminants that were likely to have been present in the diet or water were analysed, as none that may have interfered with or prejudiced the outcome of the study was known.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-24°C
- Humidity (%): 51-67%
- Air changes (per hr): Each animal room was kept at positive pressure with respect to the outside by its own supply of filtered fresh air which was passed to atmosphere and not re-circulated, providing approximately 15 air changes per hour.
- Photoperiod (hrs dark / hrs light): a 12-hour light: 12-hour dark cycle with the lights on at 06:00 GMT.

IN-LIFE DATES: From: 2000-08-23 To: 2000-12-06

Route of administration:

oral: gavage

Details on route of administration:

Animals received the test substance formulations by oral gavage at a volume-dosage of 10 mL/kg bodyweight. All animals were dosed in ascending dosage order once daily at approximately the same time each day. The volume administered to each animal was calculated from the most recently recorded scheduled bodyweight. Control animals received the vehicle at the same volume dosage over the same treatment period.

Vehicle:

water

Remarks:

reverse osmosis (RO) water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Formulations were prepared by stirring test item with an appropriate amount of reverse osmosis (RO) water until it dissolved. This solution was then diluted to the required volume and magnetically stirred for at least 5 minutes. Formulations were prepared on a weekly basis and any samples taken for analysis were taken from the bulk formulation.

VEHICLE
- Concentration in vehicle: 0.5, 2.0 or 7.5 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analytical procedure validation, the homogeneity and stability during ambient temperature storage for 3 hours, and refrigerated storage for 10 days were confirmed for test item in aqueous formulations at 0.5 mg/mL and 7.5 mg/mL. Samples of each formulation prepared for administration on one occasion during Weeks 1, 6 and 12 of the study were analysed for test material content and found to be satisfactory.

Duration of treatment / exposure:

13 weeks, except that females of the Reproductive sub-group were administered for two weeks prior to pairing, throughout pairing and gestation until Day 6 of lactation.

Frequency of treatment:

Once daily

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

No. of animals per sex per dose:

Toxicity sub-group: 10 animals per sex per dose
Neurotoxicity sub-group: 5 animals per sex per dose
Reproductive sub-group: 10 females per dose

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
In the 7-day preliminary study it was concluded that 150 mg/kg/day was unsuitable for repeated administration over 28 days due to effects observed on bodyweights and progression of clinical signs. A high dosage of 50 mg/kg/day was subsequently investigated in the 28-day study and was assessed to be the Lowest Observed Adverse Effect Level (LOAEL) with 15 mg/kg/day as the No Observed Adverse Effect Level (NOAEL). In view of the minimal effects observed at 50 mg/kg/day in the 28-day study, it was considered that this might be regarded as too cautious a choice for this study. A high dosage lying between 50 and 150 mg/kg/day was considered more appropriate. 75 mg/kg/day represents a 50% increase from the dosage used in the 28-day study and is exactly half of the dosage considered to be too high in the 7-day study.
The lower dosage represents a four fold interval with the low dosage of 5 mg/kg/day anticipated to be a no-observed effect level equating to the low dosage group (4.5 mg/kg/day) used in the 28-day study.
- Rationale for animal assignment: using a pseudo-random procedure to yield groups with approximately equal mean bodyweights.
- Fasting period before blood sampling for clinical biochemistry: overnight

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Animals and their cages/cage trays were inspected at least twice daily for evidence of reaction to treatment or ill-health.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weighed on the day that treatment commenced, weekly thereafter, and at necropsy.

FOOD CONSUMPTION: Yes
- Time schedule: With the exception of Toxicity sub-group males during the period of pairing with Reproductive subgroup females, food consumption was recorded weekly, from the commencement of treatment

OPHTHALMIC EXAMINATION: Yes
- Time schedule for examinations: During Week 13 of treatment, prior to orbital sinus blood sampling
- Dose groups that were examined: all Control and high dosage Toxicity sub-group animals

HAEMATOLOGY AND BLOOD CHEMISTRY: Yes
- Time schedule for collection of blood: During Week 13
- Anaesthetic used for blood collection: Yes (Isoflurane)
- Animals fasted: overnight
- How many animals: all animals in the Toxicity sub-group
- Parameters checked:
Samples using EDTA as an anticoagulant were examined using a Technicon H-l haematology analyser for the following characteristics:
Haematocrit (Hct), Haemoglobin concentration (Hb), Erythrocyte count (RBC), Total and differential leucocyte count (WBC), Platelet count (Plt), Mean cell haemoglobin concentration (MCHC), Mean cell haemoglobin (MCH), Mean cell volume (MCV)
Blood film - Romanowsky stain, examined by light microscopy for abnormal morphology and unusual cell types, including normoblasts.
Using citrate as an anticoagulant, samples were examined for Prothrombin time (PT).
All samples using lithium heparin as an anticoagulant were examined for:
Alkaline phosphatase (Alk. Phos), Alanine amino-transferase (ALT), Aspartate amino-transferase (AST), Gamrna-glutamyl transpeptidase (gGT), Omithine carbamyl transferase (OCT), Glucose (Gluc), Total bilirubin (Bili. Total), Total cholesterol (Chol Total), Creatinine (Creat), Urea, Total protein (Total Prot), Albumin (Alb), Albumin/globulin ratio (AlG Ratio), Sodium (Na), potassium (K) and Chloride (Cl), Calcium concentration (Ca Total), Inorganic phosphorus (Phos)

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:
Home cage observations: Before commencement of treatment (Week -1) and during Weeks 1, 2, 4, 8 and 12, at approximately the same time of day.
In the hand and standard arena observations: Before commencement of treatment (Week -1) and during Weeks 1, 2, 4, 8 and 12, at approximately the same time of day, after removal from the home cage
Manipulations: Reflexes and responses were assessed before commencement of treatment (Week -1) and during Week 12, at approximately the same time of day.
Motor activity: assessed before commencement of treatment (Week -1) and during Week 12, immediately following the manipulation tests.
- Dose groups that were examined: All Neurotoxicity sub-group animals and 5 males and 5 females from the Toxicity sub-group
- Battery of functions tested: Home cage observations, In the hand and standard arena observations, Manipulations, Motor activity

Sacrifice and pathology:

GROSS PATHOLOGY: Yes.
- Toxicity sub-group animals:
Toxicity sub-group animals were killed, following the 13 week treatment period, by carbon dioxide inhalation and subjected to a detailed necropsy. The necropsy procedure included a review of the history of each animal and a detailed examination of the external features and orifices, the neck and associated tissues and the cranial, thoracic, abdominal and pelvic cavities and their viscera. The requisite organs were weighed after being dissected free of adjacent fat and other contiguous tissue External and cut surfaces of the organs and tissues were examined as appropriate, abnormalities and interactions were noted and the required tissue samples and any abnormalities preserved in appropriate fixative.
- Neurotoxicity sub-group animals:
Following the 13 week treatment period, Neurotoxicity sub-group animals were administered sodium pentobarbitone by intra-peritoneal injection to induce deep anaesthesia. The animals were then killed by exposure of the heart and perfusion of Karnovskis fixative via the aorta. Perfusion fixation was used to ensure the highest order of preservation of nervous tissue.
The necropsy procedure included a review of the history of each animal and a detailed examination of the external features and orifices, the neck and associated tissues and the cranial, thoracic, abdominal and pelvic cavities and their viscera. The brain was weighed. External and cut surfaces of the organs and tissues were examined as appropriate, abnormalities and interactions were noted and the required tissue samples and any abnormalities preserved in appropriate fixative.

HISTOPATHOLOGY: Yes
- Toxicity sub-group animals:
With the exception of the brain, optic nerves, sciatic nerves and spinal cord, organs (including abnormalities) preserved at macroscopic necropsy were processed for all decedents and for animals from the Control and high dosage groups (Groups 3 and 2). Tissue samples were dehydrated, embedded in paraffin wax and sectioned at approximately four to five micron thicknesses. Staining was with haematoxylin and eosin, except testes, which were stained with periodic acid/schiff (PAS). Only one skeletal muscle was sample was processed.
Tissues examined: Adrenals, Epididymides, Femur, Heart, Kidneys, Liver, Lungs, Sternum, Stomach, Thyroid, Uterus
- Neurotoxicity sub-group animals:
Processing of tissue, samples was undertaken for animals from Control and high dosage groups (Groups 3 and 2).
Tissues examined: Brain, Dorsal root ganglia, Dorsal and ventral root fibres, Sciatic nerve, Spinal cord, Eyes and optic nerves (both), Skeletal (gastrocnemius) muscle (right), Sciatic nerve, Tibial nerve

Statistics:

- Bodyweights, Bodyweight changes, Organ weights:
Homogeneity of variance was tested using Bartlett's test (Bartlett, 1937). Whenever this was found to be statistically significant a Behrens-Fisher test (Cochran and Cox, 1957) was used to perform pairwise comparisons, otherwise a Dunnett's test (Dunnett, 1955/64) was used.
- Functional Observation Battery numerical data:
If the data consisted predominantly of one particular value (relative frequency of the mode exceeds 75%), the proportion of animals with different values from the mode was analysed using Fisher's Exact test. Otherwise, Bartlett's test was performed to test for variance heterogeneity between groups. Where significant (1% level) heterogeneity was found, the data were logarithmically transformed and re-tested for heterogeneity. If no statistically significant heterogeneity of variance was detected (with or without logarithmic transformation), a one way analysis of variance was carried out. If the analysis of variance showed evidence (at the 5% level) of differences between the groups, Student's t-test was used to test for differences between treatment groups and the Control group. If heterogeneity was significant and could not be stabilised by logarithmic transformation, the Kruskal-Wallis test on ranks was performed on the untransformed data. If the Kruskal-Wallis test showed evidence (5% level) of differences between the groups, the Wilcoxon Rank-Sum test was used to test for differences between the treatment groups and the Control group.
- Macropathology and micropathology: Fisher's Exact test

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

Clinical signs associated with treatment were restricted to post dose salivation for both sexes at 75 mg/kg/day. For Toxicity and Neurotoxicity sub-group animals approximately half the males and the majority of females were affected, although generally only for isolated occasions. The incidence of post dose salivation tended to be higher during the latter half of the treatment period and the lower frequency observed in the Reproductive sub-group females probably reflects their shorter treatment period. Post dose salivation is frequently observed in animals dosed via the oral gavage route and is generally considered to reflect distaste of the dosing formulation.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

There were two unscheduled deaths on the study; while both were among males receiving 20 mg/kg/day, neither death was considered to be related to treatment.
Animal number 52 was noted to have maloccluded teeth during Week 1 of the study. Although the teeth were regularly trimmed to try to prevent this having a detrimental effect on the animal's health, by Week 5 of the study it was considered necessary to kill the animal for humane reasons. It is likely that this condition pre-dated allocation to the study but was not apparent due to the small size of the animal.
Animal number 48 was noted to have Iimited use of a swollen left hindlimb during Week 8. Although the animal was isolated and rehoused in a cage with a solid-bottomed floor, the condition deteriorated and it was considered necessary to kill this animal for humane reasons during Week 11. Necropsy and histopathology confirmed the swelling and inflammation of the left hindpaw and showed atrophy of the muscle in the left hindlimb. No other similar problems were observed in animals on the study including those receiving 75 mg/kg/day and it is considered that this occurrence is coincidental and unrelated to treatment.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

For Toxicity and Neurotoxicity sub-group animals at 75mg/kg/day, combined overall bodyweight gain to Week 13 was lower than Control for both sexes, with differences in bodyweight attaining statistical significance towards the end of the treatment period.
Bodyweight gain of Toxicity and Neurotoxicity sub-group females at 5 and 20 mg/kg/day, although slightly lower than the concurrent Control, was not considered to have been affected by treatment and bodyweight gain of males in the equivalent group showed no intergroup difference.

For Reproductive sub-group females at 75mg/kg/day there was a suggestion of lower gain, compared with Control, during the two week pre-pairing period. Cumulative bodyweight gain was also slightly lower for females during gestation at this dosage but, although bodyweight at Day 1 of lactation was still lower than Control subsequent weight gain to Day 7 of lactation was superior.
Bodyweight gain of Reproductive sub-group females at lower dosages during the pre-pairing period, during gestation and during the first week of lactation was not considered to have been affected by treatment.

Food consumption and compound intake (if feeding study):

effects observed, non-treatment-related

Description (incidence and severity):

There was no marked effect of treatment on combined food consumption of Toxicity and Neurotoxicity sub-group males and females at any of the dosages investigated, although a lower intake was noted for males at 75 mg/kg/day towards the end of the study when compared with Control values.
Food consumption of Reproductive sub-group females was not obviously affected by treatment during the two week pre-pairing period or during gestation and lactation.

Food efficiency:

effects observed, treatment-related

Description (incidence and severity):

At 75 mg/kg/day the efficiency of food utiIisation was generally lower than Control for both sexes, although the effect was more marked in males, particularly in the latter half of the treatment period, and reflected the lower overall bodyweight gain observed at this dosage.
Food conversion efficiency at 5 and 20 mg/kg/day was not obviously affected by treatment.

Ophthalmological findings:

no effects observed

Description (incidence and severity):

Ophthalmic examination during Week 13 of Toxicity sub-group Control animals and those receiving 75 mg/kg/day did not reveal any adverse effects of treatment.

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Haematology investigations in Toxicity sub-group males and females during the last week of treatment did not reveal any consistent differences indicative of an obvious adverse effect of treatment, values obtained being essentially similar in all groups.
It was noted for males that white blood cell count was slightly higher than Control, principally due a slight increase in lymphocyte count. These differences were slight and were not considered to be of toxicological significance.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

Blood chemistry investigations in Toxicity sub-group males and females during the last week of treatment did not indicate any obvious adverse effect of treatment.
Blood glucose levels were noted to be lower than Control for males at 75 mg/kg/day and for females at all dosages. However intergroup differences were small, showed no clear dosage relationship and were not considered to be of toxicological significance.

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Intergroup difference in absolute and bodyweight-relative organ weights of Toxicity sub-group animals did not indicate any adverse effect of treatment. A slight reduction in absolute brain weight, but with a concomitant increase in bodyweight-relative values, was noted for males at 75 mg/kg/day and was considered to reflect the lower bodyweight observed at this dosage.
Other occasional differences (e.g. lower absolute heart and adrenal weights for males at 75 mg/kg/day) were not consistent for both sexes and were not considered to be of toxicological significance.
Brain weights for Neurotoxicity sub-group animals were consistent with that observed for Toxicity sub-group animals, with males at 75 mg/kg/day again showing a slight reduction in absolute brain weight and an increase in bodyweight-relative values.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

Macroscopic observations at necropsy of Toxicity and Neurotoxicity sub-group animals following 13 weeks of treatment were unremarkable and did not indicate any obvious adverse effect of treatment.
Macroscopic observations al necropsy of Reproductive sub-group females on Day 7 of lactation were limited to a misshappen liver for one female receiving 75 mg/kg/day.

Neuropathological findings:

no effects observed

Description (incidence and severity):

Home cage, in the hand and arena observations, manipulations and motor activity showed no findings considered to be of neurotoxicological significance.

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

Microscopic examination was confined to Toxicity and Neurotoxicity sub-group animals. Findings observed were of a type and severity commonly seen in animals of this age at this laboratory and there were no findings considered to be related to treatment.

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Remarks on result:

other: for general systemis toxic

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

neuropathology

Remarks on result:

other: for neurobehavioral toxicity

Dose descriptor:

NOAEL

Effect level:

> 75 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

food efficiency

gross pathology

haematology

histopathology: non-neoplastic

mortality

neuropathology

ophthalmological examination

organ weights and organ / body weight ratios

Critical effects observed:

no

Conclusions:

Other than lower bodyweight gain, particularly towards the end of the treatment period, treatment of test item at 75 mg/kg/day for 13 weeks was generally well tolerated by both male and female rats. While this bodyweight effect precludes 75 mg/kg/day from being classified as an overall no-effect level, this dosage was considered to be a no effect level for neurobehavioral toxicity.
Based on the findings of this study the no-effect-level for general systemic toxic is considered to be 20 mg/kg/day.

Executive summary:

The study was performed to assess the overall toxic potential, including a screen for reproductive effects, of test item when administered daily by oral gavage to the CD rat according to OECD 422 and 408. Animals on the study were distributed to three sub-groups (Toxicity, Neurotoxicity and Reproductive), with dosages of 0 (Control), 5, 20 and 75 mg/kg/day being investigated in each sub-group. The Toxicity sub-group consisted of 10 males and 10 females per group and these animals received 13 weeks of continuous daily treatment with ophthalmic, haematology and blood chemistry investigations being conducted during the final week of treatment. Organ weights were recorded at termination and tissues preserved and processed for microscopic examination. The Neurotoxicity sub-group consisted of 5 males and 5 females per group; these animals received 13 weeks of continuous daily treatment and were subjected to periodic neurobehavioural screening. At necropsy these animals were perfused with fixative to allow a full microscopic examination of the nervous system. The pool of animals assessed for neurobehavioural effects was increased to 10 per sex per group by subjecting 5 males and 5 females from the Toxicity sub-group to the same procedures. The Reproductive sub-group consisted of 10 females per group and animals were given continuous daily treatment until termination. All Control groups received the vehicle alone on the same occasions as the treated animals.

 

There were two deaths among males at 20 mg/kg/day, neither death was considered to be related to treatment.

Clinical signs associated with treatment were restricted to post dose salivation for both sexes at 75 mg/kg/day. This sign was generally observed on isolated occasion with a higher incidence in the latter half of the treatment period for Toxicity and Neurotoxicity sub-group animals.

At 75 mg/kg/day, combined bodyweight gain to Week 13 of Toxicity and Neurotoxicity sub-group animals was lower than Control for both sexes, with differences in bodyweight attaining statistical significance towards the end of the treatment period. For Reproductive sub-group females there was a suggestion of lower gain, compared with Control, during the two week pre-pairing period. Cumulative bodyweight gain was slightly lower for females during gestation and bodyweight at Day 1 of lactation was also lower.

At 5 and 20 mg/kg/day bodyweight gain of Toxicity, Neurotoxicity and Reproductive sub-group animals was unaffected by treatment.

There was no clear adverse effect of treatment observed on food intake at any of the dosages investigated. At 75 mg/kg/day food conversion efficiency was generally lower than Control, particularly for males during the last few weeks of treatment, reflecting the lower overall bodyweight gain observed at this dosage. At 5 and 20 mg/kg/day food conversion efficiency was not obviously affected by treatment.

Ophthalmic examination during Week 13 of Toxicity sub-group Controls and animals receiving 75 mg/kg/day did not reveal any adverse effects of treatment.

Haematology and blood chemistry investigations in Toxicity sub-group animals during the last week of treatment did not indicate any obvious adverse effect of treatment.

Neurobehavioural screening showed no findings considered to be of neurotoxicological significance, at any of the dosages investigated.

Occasional intergroup differences in absolute and bodyweight-relative organ weights of Toxicity subgroup animals were considered to reflect the effect on overall bodyweight and did not indicate any adverse effect of treatment.

Macroscopic necropsy of Toxicity, Neurotoxicity and Reproductive sub-group animals did not reveal any adverse effect of treatment.

Microscopic examination of Toxicity and Neurotoxicity sub-group animals at 75 mg/kg/day did not reveal any changes considered to be related to treatment.

Other than lower bodyweight gain, particularly towards the end of the treatment period, treatment of test item at 75 mg/kg/day for 13 weeks was generally well tolerated by both male and female rats. While this bodyweight effect precludes 75 mg/kg/day from being classified as an overall no-effect level, this dosage was considered to be a no effect level for neurobehavioral toxicity.

Based on the findings of this study the no-effect-level for general systemic toxic is considered to be 20 mg/kg/day.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

75 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

GLP study

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 07 November 2001 to 27 February 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Specific details on test material used for the study:

Batch number: 06104056
Purity: 99.68%

Species:

rat

Strain:

other: Crl:CD BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles river UK Limited
- Age at study initiation: 9 weeks
- Weight at study initiation: 257-346 g for males and 182-228 g for females
- Fasting period before study:
- Housing: housed 5 of same sex to a cage in suspended stainless steel cages fitted with mesh front, back and floor with stainless steel sheet sides.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 19 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 13-23°C
- Humidity (%): 26-60%
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours dark per 24 hours

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

snout only

Vehicle:

air

Mass median aerodynamic diameter (MMAD):

5.4 µm

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: ADG snout-only exposure chambers
- System of generating particulates/aerosols: the test aerosol was generated using a stainless steel jet atomiser supplied with the substance by a syringe pump.
- Air flow rate: 30 L/minute
- Method of particle size determination: once each day using a cascade impactor operated at airflow of 2 L/minute

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Analytical method: HPLC
- Column: Lichrospher 60 RP-select B, 125 mm*4.0 mm i.d, 5 um
- Mobile phase: Methanol/water 25:75 v/v
- Detector: UV 235 nm

Duration of treatment / exposure:

13 weeks, 5 days per week

Frequency of treatment:

daily, 6 hours a day

Dose / conc.:

0.012 mg/L air (nominal)

Dose / conc.:

0.03 mg/L air (nominal)

Dose / conc.:

0.12 mg/L air (nominal)

No. of animals per sex per dose:

10 males and 10 females

Control animals:

yes, concurrent vehicle

Observations and examinations performed and frequency:

CLINICAL OBSERVATIONS: Yes
- Time schedule: daily, before exposure, during exposure, as each animal return to home cage, as late as possible in working day

BODY WEIGHT: Yes
- Time schedule for examinations: on the day treatment commenced, weekly thereafter, and prior to necropsy

FOOD CONSUMPTION: Yes
- Food consumption for each animal: weekly

WATER CONSUMPTION AND COMPOUND INTAKE: Yes
- Time schedule for examinations: daily

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: before start of dosing, during week 13 of dosing
- Dose groups that were examined: all rats

HAEMATOLOGY: Yes
- Time schedule for collection of blood: in week 13
- Anaesthetic used for blood collection: Yes, isoflurane
- Animals fasted: Yes, overnight
- How many animals: all rats
- Parameters checked: Haematocrit (Hct), Haemoglobin (Hb), Erythrocyte count (RBC), Mean cell haemoglobin concentration (MCHC), Mean cell volume (MCV), Mean cell haemoglobin (MCH), Total
leucocyte count (WBC), Platelet count (Plt), Reticulocyte count (Retic)

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: in week 13
- Animals fasted: Yes, overnight
- How many animals: all rats
- Parameters checked: Glucose-hexokinase mediated assay (Gluc), Total protein (Total Prot), Albumin (Alb), Urea, Creatinine (Creat), Alkaline phosphatase (ALP), Alanine amino-transferase (ALT), Aspartate amino-transferase (AST), Total bilirubin (Bili.), Sodium (Na), potassium (K) and Chloride (Cl), Calcium (Ca), Inorganic phosphorus (Phos), Cholesterol (Chol), Triglycerides (Trig)

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, all rats were subjected to a detailed macroscopic examination.
All superficial tissues were examined visually and by palpation and the cranial roof removed to allow observation of the brain, pituitary gland and cranial nerves. After ventral mid - line incisions and san reflection, all subcutaneous tissues were examined. The condition of the thoracic viscera was noted, with due attention to the thymus, lymph nodes and heart.
The abdominal viscera were examined before and after removal; the urinary biadder was examined externally and by palpation.
The gastro - intestinal tract was examined as a whole and the stomach, caecum and portions of duodenum, jejunum, ileum, colon and oesophagus were incised and examined. The lungs were removed and all pleural surfaces examined. The liver was sectioned at intervals of a few millimetres; the idneys were incised and examined. Any abnormalities in the appearance and size of the gonads, adrenals, uterus, intra - abdominal lymph nodes and accessory reproductive organs were recorded.

HISTOPATHOLOGY: Yes
Histopathological examinations were performed on all scheduled tissues for all rats in control and high dose groups, and from respiratory tract (lungs) of low and inter dose groups. Tissue samples were embedded in paraffin wax and sectioned at approximately four to five micron thicknesses, processed and stained with haematoxylin and eosin.
Tissues examined: Adrenals, alimentary tract, aorta-thoracic, brain, Epididymides, eyes, Femur, harderian glands, head, Heart, Kidneys, lachrymal glands, larynx, Liver, Lungs, lymph nodes, mammary area-caudal, nasal turbinates, optic nerves, ovaries, pancreas, putuitary, prostate, salivary glands, Sciatic nerves, seminal vesicles, skeletal muscle-thigh, skin, Spinal cord, spleen, Sternum, testes, thymus, Thyroids, tongue, trachea, urinary bladder, uterus, vagina.

Other examinations:

Organ weight:
The following organs from each animal were dissected free of fat and weighed:
adrenals, brain, heart, kidneys, liver, lungs including bronchi, ovaries, spleen, testes

Statistics:

All statistical analyses were performed separately for males and females.
Data relating to food and water consumption were analysed on a cage basis. For all other parameters the analyses were perfomed using the individual animal as the experimental unit. Bodyweight data were analysed using weight gains. The following sequence of statistical tests was used for bodyweight, food and water consmption, clinical pathology and organ weight data.
If 75% of the data were the same value, then a frequency analysis was applied.

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

Signs seen in all groups during daily post-dose observations included red staining around eyes, wet fur and brown staining, these are consistent with method of exposure.

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Over 13 weeks, reductions in bodyweight gain were evident in all treated groups compared with control, with statistical significance being attained for high dose males.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Over 13 weeks, reductions in food consumption were evident in all treated male groups compared with control, with statistical significance being attained for high dose males.

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

effects observed, non-treatment-related

Description (incidence and severity):

Slight reduction in water consumption for inter dose males was evident, however this did not attain statistical significance.

Ophthalmological findings:

no effects observed

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

Total white blood cells, lymphocytes, eosinophils, basophils, monocytes, and large unstained cells were statistically significantly lower for treated females than control.

Clinical biochemistry findings:

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Bodyweight adjusted spleen weights, absolute mean ovary weights were statistically significantly lower for inter and high dose females than control. Absolute lung and bronchi weights were statistically significantly lower for treated females than control. These changes are small and only evident in one sex, considered to be no toxicological importance.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Incidence and distribution of all findings were considered to fall within background range.

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Nasal turbinates:
In the squamous epithelium, increased incidences of inflammatory cells in the lamina propria and epithelium were noted in several rats inthe male and female groups exposed to 0.1238 mg/L compared to controls.
In the respiratory epithelium, compared to controls, an increased incidence in inflammatory cells in the lamina propria was noted in females exposed to 0.1238 mg/L. Males exposed to 0.1238 mg/L exhibited increased incidences of respiratory epithelial hyperplasia, goblet cell hyperplasia and pseudogland formation compared to controls. Squamous metaplasia was identified in a single male treated with 0.1238 mg/L.
In the transitional epithelium, squamous metaplasia was seen in two males exposed to 0.1238 mg/L.
In the olfactory epithelium, dose - related epithelial hyperplasia, disorganisation, vacuolation and dilated ducts and atrophy of Bowman ’ s glands were seen in both male and female animals exposed to the substance at all levels. Eosinophilic inclusions in olfactory epithelium were increased in severity in some males and females exposed to 0.1238 mg/L.
Inflammatory cell infiltration in the vomeronasal organ was also seen ina single animal exposed to 0.1238 mg/L.

Testes:
Slightly increased incidences of seminiferous tubular atrophy were noted in males exposed to the substance at all levels, no effect on testicular weights.

Key result

Dose descriptor:

NOAEC

Effect level:

0.03 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

gross pathology

histopathology: non-neoplastic

Dose descriptor:

NOEC

Based on:

test mat.

Sex:

male/female

Basis for effect level:

gross pathology

histopathology: non-neoplastic

Remarks on result:

not determinable

Critical effects observed:

yes

Lowest effective dose / conc.:

0.124 mg/L air

System:

respiratory system: upper respiratory tract

Organ:

nasal cavity

Treatment related:

yes

Dose response relationship:

not specified

Relevant for humans:

not specified

Conclusions:

Exposure of rats to the substance at daily doses of 0.0124, 0.0297 and 0.1238 mg/L for 5 days per week for 13 weeks, produced efects on bodyweight gain, food consumption and white blood cell parameters. In addition changes consistent with local irritation were seen in the nasal turbinates of rats exposed to the substance. Minimal focal seminiferous tubular atrophy was evident in males at all exposure levels.
A no - observable efect level (NOEL) was not established in this study.

Executive summary:

The substance was administered to three groups of CD rats by inhalation via a snout only exposure system,6 hours per day, 5 days per week for 13 weeks. The achieved mean exposure leveis were 0.0124, 0.0297 and 0.1238 mg/L.
Dosage related reductions in bodyweight gain were evident for treated rats. However these were only statistically significant for males at the 0.1238 mg/L exposre level. Dosage related reductions in mean food consumption were evident for treated males, with statistical significance also being atained at the 0.1238 mg/L exposure level.
Dosage related reductions were also evident in certain white blood cell parameters for treated rats. These were statistically significant for females but not for males.
Histopathological examination of selected tissues following exposure of rats to the substance for 13 weeks revealed several treatment - related changes. Changes consistent with local irritation were seen in the nasal turbinates of rats exposed to the substance.
In rats, exposed to 0.1238 mg/L, increased levels of inflammatory cells in the lamina propria and epithelium of the squamous epithelium were seen in both sexes. In males, epithelial hyperplasia, goblet cell hyperplasia and pseudogland formation in the respiratory epithelium and squamous metaplasia of the transitional epithelium were noted; in females, an increased incidence of inflammatory cells in the lamina propria of the respiratory epithelium was seen. Inflammatory cell infiltration in vomeronasal organ was seen in a single male.
Dose - related changes in the olfactory epithelium, namely, epithelial hyperplasia, disorganisation, vacuolation, dilated ducts and atrophy of Bowman's glands, were noted in both sexes at all three exposure levels.
Overall, males tended to be more severely affected than females in the respiratory epithelium, whereas the severity and/or incidence of olfactory findings seemed to be marginally higher in females compared to males.
In the testes, increased incidences of minimal focal testicular seminiferous tubular atrophy were recorded at all exposure levels. The effect of this finding on fertility is unclear.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEC

0.03 mg/L

Study duration:

subchronic

Experimental exposure time per week (hours/week):

30

Species:

rat

Quality of whole database:

GLP study

System:

respiratory system: upper respiratory tract

Organ:

nasal cavity

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The substance has a Harmonised classification under CLP00 of Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). The substances Harmonised Classification for the STOT RE endpoint is “STOT RE 2 H373”.