tert-butyl 3-oxobutanoate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

Reproductivetoxicity study

The data available for tert-butyl 3-oxobutanoate (1694-31-1) and structurally similar read across chemicals was reviewed to determine thereproductive toxicity .The NOAEL for reproductive toxicity was considered to be 1000mg/kg bw/day as No effects on reproductive parameters were observed .When male and female rats were treated withtert-butyl 3-oxobutanoate (1694-31-1).Thus, comparing this value with the criteria of CLP regulation tert-butyl 3-oxobutanoate (1694-31-1)not likely to classify as reproductive toxicant.

 

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data of read across substances

Justification for type of information:

Weight of evidence approach based on structurally similar chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

other: As mentioned below

Principles of method if other than guideline:

WoE report is based on two reproductive toxicity studies on rats 1&2. Combined Repeat Dose and Reproductive / Developmental Toxicity Screening Test of test material was performed on Sprague Dawley rats.

GLP compliance:

not specified

Limit test:

no

Justification for study design:

No data available

Specific details on test material used for the study:

- Name of test material : tert-butyl 3-oxobutanoate- Molecular formula : C8H14O3- Molecular weight : 158.196 g/mol- Smiles notation : O(C(C)(C)C)C(CC(C)=O)=O- InChl : 1S/C8H14O3/c1-6(9)5-7(10)11-8(2,3)4/h5H2,1-4H3- Substance type : Organic- Physical state : Liquid

Species:

rat

Strain:

Sprague-Dawley

Details on species / strain selection:

No data available

Sex:

male/female

Details on test animals or test system and environmental conditions:

Study 1.Details on test animals and env. conditionsTEST ANIMALS- Source: No data available- Age at study initiation: 10 weeks - Weight at study initiation: 373.2 to 428.2 g for males and 227.7 to 255.3 g for females- Fasting period before study: No data available- Housing: stainless steel hanger cage in a barrier system room- Use of restrainers for preventing ingestion (if dermal): yes/no- Diet (e.g. ad libitum): solid feed (MF, Oriental Yeast Industry ) ad libitum.- Water (e.g. ad libitum): drinking water added sodium hypochlorite (about 2 ppm), ad libitum- Acclimation period: 13 daysENVIRONMENTAL CONDITIONS- Temperature (°C): 24 ± 2°C- Humidity (%):55±10%- Air changes (per hr): 13 to 15 times - Photoperiod (hrs dark / hrs light): illumination 12 hours (7 am to 7 pm)

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

water for injection

Details on exposure:

Study 1.Details on exposurePREPARATION OF DOSING SOLUTIONS:Test material mixed water for injectionDIET PREPARATION- Rate of preparation of diet (frequency):No data available- Mixing appropriate amounts with (Type of food )- Storage temperature of food: No data availableVEHICLE- Justification for use and choice of vehicle (if other than water): Test material mixed with water for injection- Concentration in vehicle: 0,100,300,1000 mg/kg bw/day- Amount of vehicle (if gavage): 10ml/kg- Lot/batch no. (if required): water for injection- Purity: No data availableStudy 2.Details on exposurePREPARATION OF DOSING SOLUTIONS:Test material mixed with tap water to form dosing solution DIET PREPARATION- Rate of preparation of diet (frequency):No data available- Mixing appropriate amounts with (Type of food )- Storage temperature of food: No data availableVEHICLE- Justification for use and choice of vehicle (if other than water): - Concentration in vehicle: 0, 50,225,1000mg/kg bw/day- Amount of vehicle (if gavage): 10ml/kg- Lot/batch no. (if required): No data available- Purity: No data available

Details on mating procedure:

Study 1.- M/F ratio per cage:1:1 - Length of cohabitation: overnight - Proof of pregnancy: [vaginal plug / sperm in vaginal smear] referred to as [day 0 / day 1] of pregnancy:the day when the sperm or vaginal plug in the vaginal plaque was confirmed the next day was taken as the 0th gestation - After ... days of unsuccessful pairing replacement of first male by another male with proven fertility. - Further matings after two unsuccessful attempts: [no / yes (explain)] - After successful mating each pregnant female was caged (how): - Any other deviations from standard protocol:

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

Study 1.7 weeks (males for a total of 49 days before the mating and for the 35 days including the mating period, for a total of 49 days in the female, 14 days before the mating in the female, a mating period (maximum 14 days), a period of gestation and a period of 3 days of nursing,)Study 2.Males were treated daily from two weeks before mating until the end of the mating period. Females were treated daily from two weeks before mating until the 4th day of lactation

Frequency of treatment:

once per day

Details on study schedule:

No data available

Remarks:

Study 1.0, 100,300,1000mg/kg bw/dayStudy 2.0, 50,225,1000mg/kg bw/day

No. of animals per sex per dose:

Study 1.Total:960 mg/kg bw/day:12male and 12 female 100 mg/kg bw/day:12male and 12 female300 mg/kg bw/day:12male and 12 female1000mg/kg bw/day:12male and 12 femaleStudy 2.Total:800 mg/kg bw/day:10 male and 10 female 50 mg/kg bw/day:10 male and 10 female225mg/kg bw/day:10 male and 10 female1000 mg/kg bw/day:10 male and 10 female

Control animals:

yes, concurrent vehicle

Details on study design:

Study 1.Dose selectionsThe dose was set from the results of the preliminary test. That is, as a result of repeated administration of 100, 300 and 1000 mg / kg of the test substance for 2 weeks, changes in general condition, body weight, food intake, hematology test, blood biochemical examination, autopsy and organ weight by administration of the test substance Was not found. Therefore, for the dose of this study, we set 1000 mg / kg as the critical dose according to the OECD guidelines to high doses, and 300 and 100 mg / kg divided by the common ratio of about 3, respectively, as medium dose and low dose .- Rationale for animal assignment (if not random):the grouping was carried out by stratified continuous randomization method based on the body weight the day before the start of administration.

Positive control:

No data available

Parental animals: Observations and examinations:

Study 1.Parental animals observation and examinationsCAGE SIDE OBSERVATIONS: yes DETAILED CLINICAL OBSERVATIONS: twice a dayTime schedule: BODY WEIGHT: YesTime schedule for examination male was measured twice a week throughout the administration period. Females are given twicea week during the administration period and the mating period before mating, pregnancy 0 (pregnancyconfirmation date), 4, 7, 10, 14, 17 and 21 days during pregnancy, nursing 0 during delivery Day) and 4 days.FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes males were measured twice a week during the administration period excluding the matingperiod. Females were measured twice a week for the administration period before mating, 1, 4, 7, 10, 14, 17 and 21 days pregnancy during pregnancy, and on nursing days 1 and 4 during the feeding period.Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: no Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes / No / No data: No data availableWATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data Time schedule for examinations: OTHER: Hematology examination, Blood biochemical examination

Oestrous cyclicity (parental animals):

Estrous cyclicity was observed

Sperm parameters (parental animals):

No data available

Litter observations:

Study 1&2STANDARDISATION OF LITTERS- Performed on day 4 postpartum: [yes/no]- If yes, maximum of [...] pups/litter ([...]/sex/litter as nearly as possible); excess pups were killed and discarded. PARAMETERS EXAMINEDThe following parameters were examined in [F1 ] offspring:number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain, physical or behavioural abnormalities, GROSS EXAMINATION OF DEAD PUPS: yes, for external abnormalitiesASSESSMENT OF DEVELOPMENTAL NEUROTOXICITY:No data availableASSESSMENT OF DEVELOPMENTAL IMMUNOTOXICITY:No data available

Postmortem examinations (parental animals):

Study 1 & 2SACRIFICE - Male animals: All surviving animals [describe when, e.g. as soon as possible after the last litters in each generation were produced.] - Maternal animals: All surviving animals [describe when, e.g. after the last litter of each generation was weaned.] GROSS NECROPSY: yes - Gross necropsy consisted of external and internal examinations HISTOPATHOLOGY / ORGAN WEIGHTS: yes The tissues indicated in Table [#] were prepared for microscopic examination and weighed, respectively.

Postmortem examinations (offspring):

Study 1 & 2SACRIFICE On the fourth day of nursing, all the newborns were exsanguinated underether anesthesia, - These animals were subjected to postmortem examinations (macroscopic and/or microscopic examination) as follows: GROSS NECROPSY: yes - Gross necropsy consisted of external examinations ,the organ and tissue were macroscopically observed HISTOPATHOLOGY / ORGAN WEIGTHS The tissues indicated in Table [#] were prepared for microscopic examination and weighed, respectively.

Statistics:

Study 1.Weight, food consumption, hematology examination, blood biochemical examination, number of days required for copulation, sexual cycle examination (estrus frequency, estrus cycle), organ weight, pregnancy period, luteinum number, implantation number, total number of births, For the number and neonatal weight, average value and standard deviation were determined for each group, and the homogeneity of dispersion was first tested by the Bartlett method between the control group and the test substance administration group. When the variance was uniform, comparison with the control group was performed using Dunnett's multiple comparison test, and when the variance was not uniform, comparison with the control group was performed using Steel's multiple comparison test. With respect to the mating rate, receiving (a) germination rate, birth rate and neonatal sex ratio, by the χ ^ 2 test, Wilcoxon rank sum test for the stillbirth rate, birth rate and 4th day survival rate of newborn babies, pathological examination , Comparison between the control group and each administration group was conducted by Mann-Whitney's U test. In both cases the significance levels were set at 1 and 5%. The measured values for newborn babies were processed in units of stomach.

Reproductive indices:

yes

Offspring viability indices:

yes

Clinical signs:

no effects observed

Description (incidence and severity):

Study 1.No change was observed in general condition in male and female Study 2.No substance-related behavioural changes were observed in the animals of either dose group

Dermal irritation (if dermal study):

not specified

Mortality:

mortality observed, non-treatment-related

Description (incidence):

Study 1.In males, there was no death in each group.In females, one patient in the 300 mg / kg group had decreased activity, slow respiration, decreased body temperature and prone posture before the 2 nd day feeding and died on the 3rd day of nursing. No deaths occurred in the 100 and 1000 mg / kg groups,Study 2.none of the male or female parent animals died

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Study 1.There was no difference between in body weight of the control group and the sex of each treated group throughout the administration period.Study 2.Body weight and body weight change was within the normal range of the control in males and females of the treated groups during all phases of the study.

Food consumption and compound intake (if feeding study):

not specified

Description (incidence and severity):

Study 2.No substance-related influence was found on absolute and relative food consumption compared to the control at the dosages of 50, 225, and 1,000 mg/kg bw/day.

Food efficiency:

not specified

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

not specified

Description (incidence and severity):

Study 2.No substance-related influence was found on absolute and relative drinking water consumption compared to the control at the dosages of 50, 225, and 1,000 mg/kg bw/day.

Ophthalmological findings:

not specified

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not specified

Behaviour (functional findings):

no effects observed

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Study 1.In males, lymphocyte infiltration of the left ventricular endocardium was observed in one patient in the 1000 mg / kg group. In addition, in one case of macroscopically enlarged spleen, 100 mg / kg group, the following findings were observed histologically, so it was judged as myeloid leukemia. That is, in this example, the femoral bone marrow is occupied by tumor cells with poor cytoplasm and relatively bright circular to elliptical nucleus, similar tumor cells are found around the portal vein of the liver, and also in the sinuses of the lobules It was diffusely diffuse. Furthermore, in the spleen, tumor cells invaded and proliferated in the whole area, replacing the normal structure of the spleen. No neoplastic changes were observed in the mesenteric lymph nodes.In females, no change was found in any organs in each group.In one case of the 300 mg / kg group who died, hepatic focal necrosis, lung thrombus, necrosis of proximal renal tubular epithelial cells of the kidneys and bleeding into tubules were observed, and ulcers in the forestomach, Erosion of the glandular stomach, atrophy of the thymus, hypertrophy of the spherical zone and bundle of the adrenal glands were also observed.Study 2.Histopathological examination of testes and epididymis organs of males dosed with 1,000 mg/kg bw/day revealed no changes in any of the treated animals.Histopathological examination of the ovaries of females dosed with 1,000 mg/kg bw/day did not give evidence for substance-related changes in any of the treated animals.

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Reproductive function: oestrous cycle:

no effects observed

Description (incidence and severity):

Study 1.there was no difference in the number of estrus and estrus cycle with the control group in each group

Reproductive function: sperm measures:

not specified

Reproductive performance:

no effects observed

Description (incidence and severity):

Study 1.In reproductive ability tests, all but one group of 100 mg / kg group was mated, and fertility was confirmed in both cases. Therefore, in the control group, 100, 300 and 1000 mg / kg group, the mating rates were 100, 91.67, 100 and 100%, respectively, the conception rates were all 100%, no difference was observed between the control group and each group It was. Also in the number of days required for copulation, no difference was observed between the control group and each group. No abnormalities were found in the autopsy of the unexposed cases and histopathological examination of the ovaries.Study 2.At the dose levels of 50 and 225 mg/kg bw/day no influence was noted on both the number of corpora lutea or implantationsIn the high-dosed dams (1,000 mg/kg bw/day) the number of corpora lutea and implants was slightly decreased compared to the control, leading to a mean pre-implantation loss of 5.0% (concurrent control: 2.0%). Pre-coital time was similar in both control animals and those of the treatment groups Likewise, the duration of pregnancy of treated animals was within the range of the control and there was no influence on the parturition.

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

clinical signs

mortality

body weight and weight gain

haematology

clinical biochemistry

organ weights and organ / body weight ratios

gross pathology

histopathology: non-neoplastic

reproductive function (oestrous cycle)

reproductive function (sperm measures)

Remarks on result:

other: Overall no toxic effects observed

Critical effects observed:

not specified

System:

other: not specified

Organ:

not specified

Treatment related:

not specified

Dose response relationship:

not specified

Relevant for humans:

not specified

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not specified

Mortality / viability:

no mortality observed

Description (incidence and severity):

Study 1.there was no difference between the survival rate of the control group and each treated group

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Study 1.there was no difference between the body weight of the neonates on the 4th day of nursing in the neonates from the control groupStudy 2. For all dose groups under investigation the body weights of pups on the 1st and the 4th lactation day was within the range of the control

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Sexual maturation:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

no effects observed

Description (incidence and severity):

Study 1.no abnormality was observed in the neonatal exterior examination in each groupStudy 2. At external observation on lactation day 4 pups did not reveal any substance-related pathological findings

Histopathological findings:

not specified

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

not specified

Basis for effect level:

viability

clinical signs

mortality

body weight and weight gain

gross pathology

Remarks on result:

other: overall no effects on developmental parameters

Critical effects observed:

not specified

System:

other: not specified

Organ:

not specified

Treatment related:

not specified

Dose response relationship:

not specified

Relevant for humans:

not specified

Reproductive effects observed:

not specified

Treatment related:

not specified

Relation to other toxic effects:

not specified

Dose response relationship:

not specified

Relevant for humans:

not specified

Table: Reproductive performance of rats treated orally with test material in the combined repeat dose and reproductive / developmental toxicity screening test

Dose (mg/ kg)	0	100	300	1000
No. of females examined	12	12	12	12
Count of estrus	3.42 ±0.51	3.83 ±0.39	3.50 ±0.52	3.75 ±0.45
Estrous cycle	3.97 ±0.10	4.00± 0.00	4.13± 0.31	4.04± 0.14
No . of mated
Male	12	12	12	12
Female	12	12	12	12
No of copulated
Male	12(100)	11(91.67)	12(100)	12(100)
Female	12(100)	11(91.67)	12(100)	12(100)
No of impregnated	12(100)	11(100)	12(100)	12(100)
No of pregnant	12(100)	11(100)	12(100)	12(100)
Duration of mating	2.08 ± 1.16	2.91 ±1.45	2.25± 1.29	3.17 ±1.59

 

a) Values are mean ±SD.

b) Values are mean: ±S.D.(day)

c) Values in parentheses represent percentages to the number of mated animals.

d) Values in par-theses represent percentages to the number of copulated animals.

 

Table: Findings of delivery of Fo dams treated orally with methyl acetoacetate and observations on their offspring in the combined repeat dose and reproductive/ developmental toxicity screening test

 

Dose (mg/ kg)	0	100	300	1000
No. of dams	12	12	12	12
Gestational days	22.42 ±0.51	22.36 ± 0.50	22.42 ± 0.51	22.33 ±0.49
No. of corpora lutea	204 (17.00 ± 0.85)	192 (17.45 ± 1.21)	214 (17.83 ±1.11)	212(17.67± 1.78)
No. of implantations	185(15.42± 1.73)	180(16.36± 1.21)	209 (17.42±1.16)*	199(16.58 ±3.15)
No. of litter	173(14.42± 1.31)	161 (14.64± 2.11)	194(16.17 ±1.27)*	185(15.42 ± 2.91)
Gestation index	100	100	100	100
No. of stillborns
Male	1	1	1	1
Female	1	1	2	2
Total	2(1.16)	2(1.24)	3(1.55)	3(1.62)
No. of live newborns	171(14.25± 1.22)	159(14.45±2.07)	191(15.92 ±1.31)	182 (15.17 ±2.98)
Birth index	92.43	88.33	91.39	91.46
Sex ratio of live newborns	1.11(90/81)	0.69(65/94)*	1.27(107/84)	1.36(106/77)
Body weight of live newborns (g)
Male On day 0	6.3 ±0.5	6.4 ±0.6	6.2 ±0.3	6.2 ±0.5
day 4	9.6 ±1.0	9.5 ±1.2	9.2 ±0.6	9.4± 1.1
Female On day 0	6.0 ±0.5	6.0 ±0.6	5.8± 0.4	5.7 ±0.4
Female On day 4	9.1 ±1.0	9.0 ±1.0	8.5 ±0.8	8.6 ±0.7
Viability index	98.83	98.74	89.01	95.05
No. of external anomalies	0	0	0	0

*P<0.05(significantly different from control)

a) Values are mean: ±S.D.

b) Values in parentheses represent mean: ±S. D.

c) Gestation index=( Number of females with live newborns/ N umber of pregnant females) x100.

d) Values in parentheses represent percentages to the number of litters.

e) Birth index=( Number of live newborns/number of implantations)x100

f )Values in parentheses represent the number of male/female live newborns.

g) Values are mean: ±S.D.

h) Viability index=(Number of live newborns on day 4 after birth/Number of live newborns) X100.

i )n=11.

Conclusions:

No Observed Adversed Effect Level (NOAEL) was considered to be 1000mg/kg bw/day for reproductive and developmental toxicity. When male and female Sprague Dawley rats were treated with tert-butyl 3-oxobutanoate (1694-31-1) orally.

Executive summary:

Data available from different studies were reviewed to determine the reproductive toxicityof  tert-butyl 3-oxobutanoate (1694-31-1).The studies are as mentioned below:

Study 1.

Reproductive and developmental toxicity study of test material was performed in male and female Sprague Dawley rats. The test material was dissolved in water for injection and administered in dose concentration0 (Vehicle), 100, 300, and 1000 mg/kg-day via oral gavage route.The dose volume was 10 mL / kg, the males were treated for a total of 49 days before the mating and for the 35 days

including the mating period, for a total of 49 days in the female, 14 days before the mating in the female, a mating period (maximum 14 days), a period of gestation and a period of 3 days of nursing, The number of animals per group was 12 male and 12 female, and the grouping was carried out by stratified continuous randomization method based on the body weight the day before the start of administration. Mating was carried out by a method in which both male and female (12 weeks old) live together overnight, and the day when the sperm or vaginal plug in the vaginal plaque was confirmed the next day was taken as the 0^thgestation. For both males and females, observation of general condition and confirmation of life and death were conducted twice a day or more for all cases. For body weight, male was measured twice a week throughout the administration period. Females are given twice a week during the administration period and the mating period before mating, pregnancy 0 (pregnancy

confirmation date), 4, 7, 10, 14, 17 and 21 days during pregnancy, nursing 0 during delivery Day) and 4 days. Regarding food intake, males were measured twice a week during the administration period excluding the mating period. Females were measured twice a week for the administration period before mating, 1, 4, 7, 10, 14, 17 and 21 days pregnancy during pregnancy, and on nursing days 1 and 4 during the feeding period. In males, there was no death in each group and no change was observed in general condition. In females, one in the 300 mg / kg group had decreased activity, slow respiration, decreased body temperature and prone posture before the 2^ndday feeding and died on the 3rd day of nursing. No deaths occurred in the 100 and 1000 mg / kg groups, and no change was observed in the general condition. There was no difference between the control group and the sex of each group throughout the administration period. A decrease in total cholesterol was observed in the 100 mg / kg group, and a decrease in γ-GTP was observed in the case of 300 mg / kg. In male, absolute and relative weight increase of spleen was observed in 300 mg / kg group. In females, no change was observed in each group. In the sexual cycle examination, there was no difference in the number of estrus and estrus cycle with the control group in each group. The conception rates were all 100%, no difference was observed between the control group and each group It was. Also in the number of days required for copulation, no difference was observed between the control group and each group. No abnormalities were found in the autopsy of the unexposed cases and histopathological examination of the ovaries. The number of female neonates was large in the 100 mg / kg group, and the sex ratio was biased. In the 300 mg / kg group, the number of implantation traces, the total number of births and the number of neonates increased. However, in each group, there was no difference between the pregnancy period, the corpus luteum number, the birth rate, the birth rate, the newborn baby weight and the stillbirth rate with the control group, and no abnormality was observed in the neonatal exterior examination in each group. In the nursing examination, there was no difference between the survival rate and the body weight of the neonates on the 4th day of nursing in the neonates from the control group. In each group, there was no effect of administration of the test substance on pregnancy period, birth rate, birth rate, newborn baby weight and stillbirth rate, and there was no expression of external table abnormality. HenceNo Observed Adverse Effect Level (NOAEL) was considered to be 1000mg/kg bw/day for reproductive and developmental toxicity.When male and femaleSprague Dawley rats were treated withtest materialorally.

Study 2

Reproduction / Development toxicity study of test material was performed on male and female Sprague Dawley/CRL: CD®BR according to OECD Guideline 421. Test material dissolved in tap water and administered in dose concentration0, 50, 225, and 1,000 mg/kg bw/day by gavage (administration volume 10 ml/kg bw/day). Males were treated daily from two weeks before mating until the end of the mating period. Females were treated daily from two weeks before mating until the 4th day of lactation. In each dose group 10animals/sex were used. All the animals were observed for behavioral changes, Body weight, and food consumption. No substance-related behavioral changes were observed in the animals of 50, 225, and 1,000 mg/kg bw/day dose group. Body weight and body weight change was within the normal range of the control in males and females of the treated groups during all phases of the study. No substance-related influence was found on absolute and relative food consumption and on drinking water consumption compared to the control at the dosages of 50, 225, and 1,000 mg/kg bw/day. In parent males no substance-related macroscopically visible changes were revealed at necropsy in any of the treated animals. Relative testes and epididymis weights of the treated males were within the range of the control group. Histopathological examination of these organs of males dosed with 1,000 mg/kg bw/day revealed no changes in any of the treated animals. Also in parent females no substance-related pathological findings had been revealed at necropsy. Histopathological examination of the ovaries of females dosed with 1,000 mg/kg bw/day did not give evidence for substance-related changes in any of the treated animals. At the dose levels of 50 and 225 mg/kg bw/day no influence was noted on both the number of corpora lutea or implantations. In the 1000mg/kg bw /day dosed dams the number of corpora lutea and implants was slightly decreased compared to the control, leading to a mean pre-implantation loss of 5.0% (concurrent control: 2.0%). Pre-coital time was similar in both control animals and those of the treatment groups. Also the duration of pregnancy of treated animals was within the range of the control and there was no influence on the parturition. After birth, for the animals treated with 50 or 225 mg/kg bw/day there were no substance-related biological differences in comparison to the control group. The number of pups alive was not influenced, neither was sex distribution of the pups. Stillbirths or macroscopically visible malformed pups did not occur. The reproduction indices (birth index, live birth index, viability index) were not influenced and neither was maternal brood care. At the dose level of 1,000 mg/kg bw/day the number of pups at birth and during the 4-day lactation period was slightly decreased compared to the control correlating with the reduced number of implants. Hence, the mean post-implantation loss was increased to 13.2% (concurrent control: 5.9%) and the mean birth index and live birth index (both: 86.8%) were decreased compared to the indices of the concurrent control (both: 94.1) However, the mean viability index (97.6%) was in the range of the concurrent control (93.7%).For all dose groups under investigation the body weights of pups on the 1st and the 4th lactation day was within the range of the control. At external observation on lactation day 4 pups did not reveal any substance-related pathological findings. HenceNo Observed adverse Effect Level (NOAEL) was considered to be 1000mg/kg/day for reproductive and developmental toxicity.When femaleSprague Dawley rats were treated with test material orally.

Based on the data available from different studies, tert-butyl 3-oxobutanoate (1694-31-1) did not showedreproductive toxicityat dose concentration 1000mg/kg bw/day . Hence the test chemical is not likely to classify as a reproductive toxicant as per the criteria mentioned in CLP regulation.

Effect on fertility: via oral route

Endpoint conclusion:

no study available

Dose descriptor:

NOAEL

1 000 ng/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

Data is Klimicsh 2 and from authoritative database

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

Reproductive toxicity study

Data available from different studies were reviewed to determine thereproductive toxicityof  tert-butyl 3-oxobutanoate (1694-31-1).The studies are as mentioned below:

Study 1.

Reproductive and developmental toxicity study of test material was performed in male and female Sprague Dawley rats. The test material was dissolved in water for injection and administered in dose concentration0 (Vehicle), 100, 300, and 1000 mg/kg-day via oral gavage route.The dose volume was 10 mL / kg, the males were treated for a total of 49 days before the mating and for the 35 days

including the mating period, for a total of 49 days in the female, 14 days before the mating in the female, a mating period (maximum 14 days), a period of gestation and a period of 3 days of nursing, The number of animals per group was 12 male and 12 female, and the grouping was carried out by stratified continuous randomization method based on the body weight the day before the start of administration. Mating was carried out by a method in which both male and female (12 weeks old) live together overnight, and the day when the sperm or vaginal plug in the vaginal plaque was confirmed the next day was taken as the 0^thgestation. For both males and females, observation of general condition and confirmation of life and death were conducted twice a day or more for all cases. For body weight, male was measured twice a week throughout the administration period. Females are given twice a week during the administration period and the mating period before mating, pregnancy 0 (pregnancy

confirmation date), 4, 7, 10, 14, 17 and 21 days during pregnancy, nursing 0 during delivery Day) and 4 days. Regarding food intake, males were measured twice a week during the administration period excluding the mating period. Females were measured twice a week for the administration period before mating, 1, 4, 7, 10, 14, 17 and 21 days pregnancy during pregnancy, and on nursing days 1 and 4 during the feeding period. In males, there was no death in each group and no change was observed in general condition. In females, one in the 300 mg / kg group had decreased activity, slow respiration, decreased body temperature and prone posture before the 2^ndday feeding and died on the 3rd day of nursing. No deaths occurred in the 100 and 1000 mg / kg groups, and no change was observed in the general condition. There was no difference between the control group and the sex of each group throughout the administration period. A decrease in total cholesterol was observed in the 100 mg / kg group, and a decrease in γ-GTP was observed in the case of 300 mg / kg. In male, absolute and relative weight increase of spleen was observed in 300 mg / kg group. In females, no change was observed in each group. In the sexual cycle examination, there was no difference in the number of estrus and estrus cycle with the control group in each group. The conception rates were all 100%, no difference was observed between the control group and each group It was. Also in the number of days required for copulation, no difference was observed between the control group and each group. No abnormalities were found in the autopsy of the unexposed cases and histopathological examination of the ovaries. The number of female neonates was large in the 100 mg / kg group, and the sex ratio was biased. In the 300 mg / kg group, the number of implantation traces, the total number of births and the number of neonates increased. However, in each group, there was no difference between the pregnancy period, the corpus luteum number, the birth rate, the birth rate, the newborn baby weight and the stillbirth rate with the control group, and no abnormality was observed in the neonatal exterior examination in each group. In the nursing examination, there was no difference between the survival rate and the body weight of the neonates on the 4th day of nursing in the neonates from the control group. In each group, there was no effect of administration of the test substance on pregnancy period, birth rate, birth rate, newborn baby weight and stillbirth rate, and there was no expression of external table abnormality. HenceNo Observed Adverse Effect Level (NOAEL) was considered to be 1000mg/kg bw/day for reproductive and developmental toxicity.When male and femaleSprague Dawley rats were treated withtest materialorally.

Study 2

Reproduction / Development toxicity study of test material was performed on male and female Sprague Dawley/CRL: CD®BR according to OECD Guideline 421. Test material dissolved in tap water and administered in dose concentration0, 50, 225, and 1,000 mg/kg bw/day by gavage (administration volume 10 ml/kg bw/day). Males were treated daily from two weeks before mating until the end of the mating period. Females were treated daily from two weeks before mating until the 4th day of lactation. In each dose group 10animals/sex were used. All the animals were observed for behavioral changes, Body weight, and food consumption. No substance-related behavioral changes were observed in the animals of 50, 225, and 1,000 mg/kg bw/day dose group. Body weight and body weight change was within the normal range of the control in males and females of the treated groups during all phases of the study. No substance-related influence was found on absolute and relative food consumption and on drinking water consumption compared to the control at the dosages of 50, 225, and 1,000 mg/kg bw/day. In parent males no substance-related macroscopically visible changes were revealed at necropsy in any of the treated animals. Relative testes and epididymis weights of the treated males were within the range of the control group. Histopathological examination of these organs of males dosed with 1,000 mg/kg bw/day revealed no changes in any of the treated animals. Also in parent females no substance-related pathological findings had been revealed at necropsy. Histopathological examination of the ovaries of females dosed with 1,000 mg/kg bw/day did not give evidence for substance-related changes in any of the treated animals. At the dose levels of 50 and 225 mg/kg bw/day no influence was noted on both the number of corpora lutea or implantations. In the 1000mg/kg bw /day dosed dams the number of corpora lutea and implants was slightly decreased compared to the control, leading to a mean pre-implantation loss of 5.0% (concurrent control: 2.0%). Pre-coital time was similar in both control animals and those of the treatment groups. Also the duration of pregnancy of treated animals was within the range of the control and there was no influence on the parturition. After birth, for the animals treated with 50 or 225 mg/kg bw/day there were no substance-related biological differences in comparison to the control group. The number of pups alive was not influenced, neither was sex distribution of the pups. Stillbirths or macroscopically visible malformed pups did not occur. The reproduction indices (birth index, live birth index, viability index) were not influenced and neither was maternal brood care. At the dose level of 1,000 mg/kg bw/day the number of pups at birth and during the 4-day lactation period was slightly decreased compared to the control correlating with the reduced number of implants. Hence, the mean post-implantation loss was increased to 13.2% (concurrent control: 5.9%) and the mean birth index and live birth index (both: 86.8%) were decreased compared to the indices of the concurrent control (both: 94.1) However, the mean viability index (97.6%) was in the range of the concurrent control (93.7%).For all dose groups under investigation the body weights of pups on the 1st and the 4th lactation day was within the range of the control. At external observation on lactation day 4 pups did not reveal any substance-related pathological findings. HenceNo Observed adverse Effect Level (NOAEL) was considered to be 1000mg/kg/day for reproductive and developmental toxicity.When femaleSprague Dawley rats were treated withtest materialorally.

Based on the data available from different studies, tert-butyl 3-oxobutanoate (1694-31-1) did not showedreproductive toxicityat dose concentration 1000mg/kg bw/day . Hence the test chemical is not likely to classify as a reproductive toxicant as per the criteria mentioned in CLP regulation.

Effects on developmental toxicity

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Justification for classification or non-classification

Thus, comparing this value with the criteria of CLP regulation tert-butyl 3-oxobutanoate (1694-31-1)not likely to classify as reproductive toxicant.