Diisopropyl adipate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

Reproductive Toxicity Study:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0.1262, 0.3786, 0.7572 and 1.2619 ml/kg bw. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses. The following parameters of adverse effects were investigated, embryonic-fetal toxicity, as evidenced by resorptions and stillbirths, gross (external) malformations of fetuses, skeletal malformations, visceral abnormalities, and fetal size (weight). In all evaluations. both viable and nonviable fetuses were considered. After treatment it was observed that, only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group. No effects on the estrous cyclicity of the maternal animals was observed. Also, no effects on the reproductive parameters was observed. In fetal examinations, no effects on the body weights and the viability of the fetus was observed. Also, no significant effects on gross abnormalities except some sporadic cases of skeletal and visceral malformations were observed in the fetus treated with the test chemical.  Thus, based on all the observations and results, it was concluded that the NOAEL for the test chemical was 1.269 ml/Kg bw.

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from a peer reviewed journal.

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD 414 (PreNatal Developmental Toxicity Screening Test)

Principles of method if other than guideline:

The above experiment was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals.

GLP compliance:

not specified

Justification for study design:

No Data Available

Specific details on test material used for the study:

- Appearance: Colourless Liquid
- Molcular weight: 230.302 g/mol
- Substance type: Organic

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:

TEST ANIMALS
- Source: No Data Available
- Age at study initiation: No Data Available
- Weight at study initiation: Females: 175-225 g.
- Fasting period before study: No Data Available
- Housing: The test animals were housed in the individual cages.
- Use of restrainers for preventing ingestion (if dermal): no
- Diet (e.g. ad libitum): Food was provided ad libitum.
- Water (e.g. ad libitum): Fresh tap was provide ad libitum.
- Acclimation period: No Data Available

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22-27°C
- Humidity (%): No Data Available
- Air changes (per hr): No Data Available
- Photoperiod (hrs dark / hrs light): No Data Available

Route of administration:

intraperitoneal

Vehicle:

unchanged (no vehicle)

Details on exposure:

Details on exposure
PREPARATION OF DOSING SOLUTIONS: The test chemical was administered to the animals in at four dosage levels: one-thirtieth, one-tenth, one-fifth, and one-third of their acute LD-50 values.

DIET PREPARATION
- Rate of preparation of diet (frequency): No Data Available
- Mixing appropriate amounts with (Type of food):No Data Available
- Storage temperature of food: No Data Available

VEHICLE
- Justification for use and choice of vehicle (if other than water): No Data Available
- Concentration in vehicle: No Data Available
- Amount of vehicle (if gavage): No Data Available
- Lot/batch no. (if required): No Data Available
- Purity: No Data Available

Details on mating procedure:

Details of mating
- M/F ratio per cage: (1:5) Five female rats were housed with one male.
- Length of cohabitation: Mating was conducted on 13 days.
- Proof of pregnancy: [vaginal plug / sperm in vaginal smear] referred to as [day 0 / day 1] of pregnancy: The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0, with the following day being Day 1 of the gestation period.
- After ... days of unsuccessful pairing replacement of first male by another male with proven fertility. No Data Available
- Further matings after two unsuccessful attempts: [no / yes (explain)] No Data Available
- After successful mating each pregnant female was caged (how): The female rats were moved to individual cages, where they were kept undisturbed except for specified injections.
- Any other deviations from standard protocol: No Data Available

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No Data Available

Duration of treatment / exposure:

No Data Available

Frequency of treatment:

No Data Available

Details on study schedule:

No Data Available

Remarks:

0.1262, 0.3786, 0.7572 and 1.2619 ml/kg bw intraperitoneally

No. of animals per sex per dose:

There were 31 groups, each composed of five female rats.

Control animals:

not specified

Details on study design:

No Data Available

Positive control:

No Data Available

Parental animals: Observations and examinations:

On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.

Oestrous cyclicity (parental animals):

Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metestrus, or diestrus) was determined according to cell types found in the vaginal smear.

Sperm parameters (parental animals):

No Data Available

Litter observations:

The following parameters of adverse effects were investigated:
(a) embryonic-fetal toxicity, as evidenced by resorptions and stillbirths,
(b) gross (external) malformations of fetuses,
(c) skeletal malformations.
(d) visceral abnormalities, and
(e) fetal size (weight).

In all evaluations. both viable and nonviable fetuses were considered

Postmortem examinations (parental animals):

On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.

Postmortem examinations (offspring):

(b) gross (external) malformations of fetuses,
(c) skeletal malformations.
(d) visceral abnormalities were observed.

Statistics:

No Data Available

Reproductive indices:

Implantation Index, Resorption Index, Uterine Index.

Offspring viability indices:

Fetal viability index.

Clinical signs:

not specified

Dermal irritation (if dermal study):

not specified

Mortality:

not specified

Body weight and weight changes:

not specified

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

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

not specified

Reproductive performance:

no effects observed

The number of resorptions observed in the animals were sporadic and thus were not considered as treatment related.

Dose descriptor:

NOAEL

Effect level:

1.262 other: ml/Kg

Based on:

test mat.

Sex:

female

Basis for effect level:

gross pathology

reproductive performance

Remarks on result:

other: Not Specified

Critical effects observed:

not specified

System:

other: Not Specified

Clinical signs:

not specified

Dermal irritation (if dermal study):

not specified

Mortality / viability:

no mortality observed

Description (incidence and severity):

No mortality was observed at any treated dose levels of the tes chemical.

Body weight and weight changes:

no effects observed

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:

effects observed, non-treatment-related

Description (incidence and severity):

No significant effects on gross abnormalities except some sporadic cases of skeletal and visceral malformations were observed in the fetus treated with the test chemical.

Histopathological findings:

not specified

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1.127 other: ml/Kg

Based on:

test mat.

Sex:

male/female

Basis for effect level:

viability

mortality

body weight and weight gain

gross pathology

Remarks on result:

other: Not Specified

Critical effects observed:

not specified

System:

other: Not Specified

Reproductive effects observed:

not specified

Treatment related:

not specified

Conclusions:

Based on all the observations and results, it was concluded that the NOAEL for the test chemical was 1.269 ml/Kg bw.

Executive summary:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0.1262, 0.3786, 0.7572 and 1.2619 ml/kg bw. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses. The following parameters of adverse effects were investigated, embryonic-fetal toxicity, as evidenced by resorptions and stillbirths, gross (external) malformations of fetuses, skeletal malformations, visceral abnormalities, and fetal size (weight). In all evaluations. both viable and nonviable fetuses were considered. After treatment it was observed that, only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group. No effects on the estrous cyclicity of the maternal animals was observed. Also, no effects on the reproductive parameters was observed. In fetal examinations, no effects on the body weights and the viability of the fetus was observed. Also, no significant effects on gross abnormalities except some sporadic cases of skeletal and visceral malformations were observed in the fetus treated with the test chemical.  Thus, based on all the observations and results, it was concluded that the NOAEL for the test chemical was 1.269 ml/Kg bw.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

119 mg/kg bw/day

Study duration:

chronic

Species:

rat

Quality of whole database:

The data is K2 level as the data has been obtained from reliable publication.

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 Summaries:

The summaries of the data from the reproductive toxicity studies is as follows:

Reproductive Toxicity Study 1:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0.1262, 0.3786, 0.7572 and 1.2619 ml/kg bw. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses. The following parameters of adverse effects were investigated, embryonic-fetal toxicity, as evidenced by resorptions and stillbirths, gross (external) malformations of fetuses, skeletal malformations, visceral abnormalities, and fetal size (weight). In all evaluations. both viable and nonviable fetuses were considered. After treatment it was observed that, only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group. No effects on the estrous cyclicity of the maternal animals was observed. Also, no effects on the reproductive parameters was observed. In fetal examinations, no effects on the body weights and the viability of the fetus was observed. Also, no significant effects on gross abnormalities except some sporadic cases of skeletal and visceral malformations were observed in the fetus treated with the test chemical.  Thus, based on all the observations and results, it was concluded that the NOAEL for the test chemical was 1.269 ml/Kg bw.

Reproductive Toxicity Study 2:

In a reproductive toxicity study, male and femaleWistar ratswere exposed to test chemical orally in the concentration of 0 or 1000 mg/kg/day. The animals were observed for mortality, clinica signs, change in body weight, feed comsumption, hematology, gross pathology, organ weight and histopathology examination. The results of the study revealed, no substance-related toxic changes in survival, body weight and food consumption of treated rats at 1000mg/kg as compared to control.Statistically significant increase in hemoglobin count and mean corpuscular hemoglobin concentration(MCHC)were observed in male rats. During recovery, increased neutrophil and decreased lymphocyte count were observed in 1000 mg/kg /day-treated male rat as compare to control. Changes observed in neutrophils and lymphocytes was not substance-related and may due to the pre-analytical and analytical variables or incidental. No effects were observed on urinalysis,motor activity and gross pathology of treated rats.Increased absolute and relative weight of kidneys in males, and absolute kidney weight relative and ovaries weight in females. Tubular degeberation of kidneys and MNC infiltration in the lungs and trachea were observed in male and female rats treated with 1000 mg/kg/day. However, the observed changes were not substance-related since the changes were regarded to be due to inflammatory or elevation of the glomerular filtration rate and altered tubular fluid flow.No histopathological changes were observed in testes, epididymides, ovaries, mammary glands or uterus of treated rats as compared to control. Therefore, NOAEL was considered to be 1000 mg/kg/day when male and female Wistar rats were orally exposed to test chemical for 28 days by oral gavage.

Reproductive Toxicity Study 3:

The above study was performed to assess and evaluate the effects of the test chemical on the reproductive and developmental parameter of the test animals.For the test, Sprague-Dawley rats (Crj: CD, SPF), 7 weeks of age were used for both males and females. Animals were preliminarily kept for quarantine and acclimatization for one week after the arrival, and animals not abnormal in the general condition were subjected to the test. The animals were housed in a barrier room of a barrier system conditioned at a temperature of 24 ± 1 ° C., a relative humidity of 55 ± 5%, a ventilation frequency of about 15 times / hour, and a lighting 12 hours (7 am to 7 pm) They were individually housed in a cage and raised, and allowed to take solid feed (CA-1, Japan Clea) and tap water ad libitum. For the mother animals after 18th gestation, metal floorboards were laid on the floor of breeding cages and wood chips were supplied as beddings as appropriate.Both male and female animals were grouped by randomized stratified random extraction method based on the body weight measured before the administration on the administration start day (1st day of administration), and 13 male and 13 female each were prepared for each group.The dose of the test chemical was 100, 300 and 1000 mg / kg based on the results of the preliminary test (DRF studies). In the control group of rats, corn oil used as a vehicle, was administered under the same conditions as the test chemical.For each males, the doses of each dose were 14 consecutive days before the mating, 14 days of the mating period and 42 consecutive days of 14 days after the end of the mating period, and for females a cross between 14 days prior to mating and up to 14 days. It was administered orally using a gavage tube for rats once a day for the period (up to mating establishment) and until the third day of nursing after parturition throughout the gestation period.For observations, all males and females were observed daily for the duration of the study.For both males and females, body weight was measured once a week during the test period [male: administration 1, 8, 15, 22, 29, 36, 43, female: administration 1, 8, 15]. On mating females females at 0, 7, 14, and 20 days of age, body weight at 0 and 4 days after delivery (female 0 and 4 days) was measured for females delivered. For both males and females, the bait weight was measured on the same day as the body weight measurement day for all cases, and the food consumption for one week was calculated. No food intake was measured during the 2 week mating period. For mating females, food intake was measured between 0 to 7, 7 to 14, and 14 to 20 days of pregnancy, and further for delivering females at 0 to 4 days of feeding. Mating was carried out with the male and female animals in the same group living together all day for one day, from the evening of 15th administration (administration start date = 1 day of administration) for a maximum of 2 weeks. Confirmation of copulation was made every morning by examining the presence of sperm in the vaginal plug or vaginal plaque and the females confirmed to be mated were separated from the male starting from that day as the 0th day of pregnancy and raised individually.For male animals, on the day after administration 42 days, they were exsanguinated and killed under pentobarbital anesthesia and necropsied. At that time, kidney, spleen, testis and epididymis were excised and weighed. In addition, testis and epididymis were fixed in Bouin's solution, and histopathological examination was conducted for high dose administration group and control group. Among the female animals, the delivered animals were sacrificed on the fourth day of nursing, the matings were confirmed but the animals which did not deliver were exsanguinated under pentobarbital anesthesia on the 25th day of pregnancy and necropsied. At that time, the kidney and spleen were excised and weighed. Also, ovaries and uterus were also removed, ovary counted pregnancy corpus luteum under a stereomicroscope, was applied for uterus to confirm the number of implantation, and the implantation rate was calculated. Regarding the ovaries of infertile animals, further pathological examination was performed after fixation to Bouin's solution.The number of births,on the 0th day of nursing and the child's delivery rate.Was obtained. Also, the presence or absence of external abnormality in the newborn baby and gender were examined.Body weight (litter weight) was measured for each sex on a 0-day and a 4-day nursing, and average birth weight (litter weight / number of measurement children) was obtained for each abdomen.Births were sacrificed by ether inhalation on 4th day of nursing, necropsied, and the presence or absence of abnormality in the external surface and internal organs was examined. After all the observations,No dead animals were observed in any of the administration groups. n each administration group of the test chemical, from 2 days of administration, animals showing transient salivation after administration were observed. The number of animals showing salivation increased depending on the dose, in male animals, 3 in 100 mg / kg administration group, 11 in 300 mg / kg administration group and 13 in 1000 mg / kg administration group In female animals, it was found in 2 subjects in the 100 mg / kg administration group, 9 cases in the 300 mg / kg administration group and 13 mice in the 1000 mg / kg administration group. In addition, no change in general condition was observed. In males, the measured value in the 1000 mg / kg administration group was slightly low, but no significant difference was observed between the control group and the test chemical administration group. In females, no effect of the test chemical administration was observed at any time. There was no significant difference in food consumption between males and females between the control group and the test chemical administration group. In males, the specific organ weight value of the kidney significantly increased in the 1000 mg / kg administration group and the specific organ weight value of the spleen significantly increased in the group administered with 100 and 1000 mg / kg, but in the testis and epididymal weight , No significant difference was observed between the control group and the test chemical administration group. In the females, the relative weight of the kidney increased somewhat in the 1000 mg / kg administration group and the actual weight of the spleen significantly increased in the 100 mg / kg administration group, but the specific weight of the spleen included the control group and treated group. There was no significant difference between each group treated with the test chemical. In the lungs, 2 animals in the 300 mg / kg administration group, 1 animal in the 1000 mg / kg administration group received dark red spots, one animal of 100 and 1000 mg / kg administration group showed discoloration or grayish white spots. Regarding the kidney, the renal pelvic dilation was observed in each of the control group and each animal of the 300 mg / kg administration group, 100 and 1000 mg / kg administration group, and each animal of the 100 and 300 mg / kg administration groups, a depression was confirmed. For the liver, diaphragmatic hernia in the 100 mg / kg administration group, darkening in the 1000 mg / kg administration group, swelling in the 100 mg / kg administration group and 1000 mg / kg administration group with 1 white point in each group was observed. Diarrhea in the jejunum in the 300 mg / kg administration group, yellowish white nodules in the epididymis in the control group were found in each animal. However, none of the findings showed a dose-dependent relationship in its expression. In the testis, partial digestion of the seminiferous tubules and germ cell reduction were observed in one of the control group. Spermatidoblastoma was found in one epididymus in the control group, infiltration of mild lymphocytes was observed in 5 mice in the control group and 3 mice in the 1000 mg / kg administration group, but administration of the test chemical. There were no abnormal findings that could be attributed to the test chemical. No abnormal findings were found in the ovaries of infertile females, each of which was observed in each of the control group and test chemical administration group. There was no difference between the control group and the test chemical administration group at all for the copulation rate and conception rate. In addition, no significant difference was observed between the control group and the test chemical administration group for the number of days before mating and the number of estrus during that period. In fetal parameters, it was observed that, in the 1000 mg / kg administration group, the neonatal survival rate on the 4th day of nursing was significantly lower than that of the control group, but the delivery rate, the birth rate, the birth rate and the sex ratio included the control group and the treated group. There was no significant difference between the treated group and the treated group. Weight of 0 and 4 days of nursing in the 1000 mg / kg administration group showed somewhat low values, but no significant difference was observed with the control group. In morphological observation of babies, no malformations suggesting the effect of the test chemical administration were observed. Thus, based on all the observations and results, it was concluded that, the NOAEL for parental parameters was observed to be 300 mg/kg bw and for the fetal parameters it was observed to be 1000 mg/kg bw.

Effects on developmental toxicity

Description of key information

Developmental Toxicity Study:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0, 119.89, 359.67, 719.34 or 1198.805 mg/kg/day on Day 5, 10 and 15 days of gestation with the test chemical. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.The parameters resorptions, number of corpora lutea, fetal survival, mean fetal weight and gross, skeletal and visceral abnormalities were analysed. No increased level of fetal deaths was noted and no effect of teratogenicity was observed. Slight increase in gross and skeletal abnormalities was observed at concentrations above 119.89 mg/kg/day of the test chemical. The no observed adverse effect level (NOAEL) value of diisopropyl adipate was found at dose level of 119.89 mg/kg/day since at this dose no effects were observed on rat fetuses.

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from a publication.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Principles of method if other than guideline:

Embryonic-fetal toxicity and teratogenic study of the test chemical in rats

GLP compliance:

not specified

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Sprague-Dawley Inc., Madison, WI
- Age at study initiation: No data available
- Weight at study initiation: 175-225 g
- Fasting period before study:No data available
- Housing: Females were housed individually after confirmed pregnancy.
- Diet (e.g. ad libitum): Purina laboratory chow, ad libitum
- Water (e.g. ad libitum): Tap water, ad libitum
- Acclimation period: Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22-27°C
- Humidity (%): No data available
- Air changes (per hr): No data available
- Photoperiod (hrs dark / hrs light): No data available

IN-LIFE DATES: From: To: No data available

Route of administration:

intraperitoneal

Vehicle:

unchanged (no vehicle)

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No Data Available

Details on mating procedure:

- Impregnation procedure: Cohoused
- If cohoused: Yes
- M/F ratio per cage: 1 male/5 females
- Length of cohabitation: Until confirmed pregnancy
- After ... days of unsuccessful pairing replacement of first male by another male with proven fertility.N/A
- Further matings after two unsuccessful attempts: N/A
- Verification of same strain and source of both sexes: [yes / no (explain)]
- Proof of pregnancy: Presence of sperm in the vaginal smear, being Day 0 of gestation.
- After successful mating each pregnant female was caged (how): Individually and was kept undisturbed except for specified injections.
- Any other deviations from standard protocol: N/A

Duration of treatment / exposure:

Upto day 20 of gestation

Frequency of treatment:

On 5th, 10th, and 15th days of gestation

Remarks:

Doses / Concentrations:
0, 119.89, 359.67, 719.34 or 1198.805 mg/kg
Basis:

No. of animals per sex per dose:

Blunt needle (injection): 5 pregnant female rats
Distilled water: : 5 pregnant female rats
Normal saline: : 5 pregnant female rats
Cottonseed oil: : 5 pregnant female rats
Dipropyl adipate :
119. 89 mg/Kg: 5 pregnant female rats
359.67 mg/Kg: 5 pregnant female rats
719.34 mg/Kg: 5 pregnant female rats
1198.805 mg/Kg: 5 pregnant female rats

Control animals:

other: Blunt end needle

Details on study design:

No Data Available

Maternal examinations:

No Data Available

Ovaries and uterine content:

On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.

Fetal examinations:

Body weight : Mean fetal weights in the mid- and high-dose groups were significantly lower than in the control group.
Gross pathology: There was a significant increase of gross fetal abnormalities was noted in the mid and high dosed groups as compared to control.
Skeletal abnormalities: SSkeletal abnormalities occurred at only at higher dose i.e 5.3% .
Visceral abnormalities No changes were observed

Statistics:

Acute LD50 values, 95% confidence limits, and slopes were calculated by Cornfield and Mantel’s modification of Karber’s method.

Indices:

No data available

Historical control data:

No data available

Clinical signs:

not specified

Dermal irritation (if dermal study):

not specified

Mortality:

not specified

Body weight and weight changes:

not specified

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

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group.

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Details on results:

Only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group.

Number of abortions:

not specified

Pre- and post-implantation loss:

not specified

Total litter losses by resorption:

effects observed, non-treatment-related

Description (incidence and severity):

Only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group.

Early or late resorptions:

effects observed, non-treatment-related

Description (incidence and severity):

Only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group.

Dead fetuses:

not specified

Changes in pregnancy duration:

not specified

Changes in number of pregnant:

not specified

Other effects:

not specified

Details on maternal toxic effects:

Only one resorption site was ohserved in the test chemical group. No other gross pathological effects were observed in the test chemical treated group.

Dose descriptor:

NOAEL

Effect level:

119.89 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

early or late resorptions

gross pathology

maternal abnormalities

total litter losses by resorption

Remarks on result:

other: Not Specified

Abnormalities:

not specified

Fetal body weight changes:

no effects observed

Reduction in number of live offspring:

not specified

Changes in sex ratio:

not specified

Changes in litter size and weights:

not specified

Changes in postnatal survival:

not specified

External malformations:

effects observed, non-treatment-related

Description (incidence and severity):

High cases of external malformations were observed at 719.34 or 1198.805 mg/kg.

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

High cases of skeletal malformations were observed at 719.34 or 1198.805 mg/kg.

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

High cases of Visceral malformations were observed at 719.34 or 1198.805 mg/kg.

Other effects:

not specified

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:yes

Dose descriptor:

NOAEL

Effect level:

119.89 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: teratogenicity

Dose descriptor:

LOAEL

Effect level:

359.67 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: teratogenicity

Abnormalities:

not specified

Developmental effects observed:

not specified

Treatment related:

not specified

Conclusions:

The no observed adverse effect level (NOAEL) value of the test chemical was found to be 119.89 mg/kg bw/day.

Executive summary:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0, 119.89, 359.67, 719.34 or 1198.805 mg/kg/day on Day 5, 10 and 15 days of gestation with the test chemical. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.The parameters resorptions, number of corpora lutea, fetal survival, mean fetal weight and gross, skeletal and visceral abnormalities were analysed. No increased level of fetal deaths was noted and no effect of teratogenicity was observed. Slight increase in gross and skeletal abnormalities was observed at concentrations above 119.89 mg/kg/day of the test chemical. The no observed adverse effect level (NOAEL) value of diisopropyl adipate was found at dose level of 119.89 mg/kg/day since at this dose no effects were observed on rat fetuses.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

119 mg/kg bw/day

Study duration:

chronic

Species:

rat

Quality of whole database:

Data is from a Klimisch 2 database and from a reliable publication.

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

Developmental Toxicity Study Summaries:

The summaries of the data for the developmental toxicity studies is as follows:

Developmental Toxicity Study 1:

A study was performed to evaluate and assess the effect of the test chemical on the maternal animals and on the fetus of the treated maternal animals. In this study, the test chemical was administered to the test animals via the intraperitoneal route at doses of 0, 119.89, 359.67, 719.34 or 1198.805 mg/kg/day on Day 5, 10 and 15 days of gestation with the test chemical. Female rats were selected for experimentation only after observation of at least two complete 4- or 5-day estrus cycles. Occurrence of estrus was determined by daily vaginal smears, obtained by introducing 0.2 ml. of fresh, clean tap water into the vagina with a smooth. clean. sterile medicine dropper, withdrawing a part of the liquid, and transferring it to a clean slide. The slide was examined microscopically while fresh, and the stage of estrus (proestrus, metstrus, or diestrus) was determined according to cell types found in the vaginal smear. Test animals were adult, virgin female, Sprague-Dawley rats, weighing 175-225 g. Adult, male rats of this strain were utilized as the “stud pool.” Five female rats were housed with one male in a large cage at room temperature (22-27“) with foods and fresh tap water provided ad libitum. The onset of gestation was established by the presence of sperm in the vaginal smear and was designated as Day 0. with the following day being Day 1 of the gestation period. At this time, the female rats were moved to individual cages, where they were kept undisturbed except for specified injections. There were 31 groups, each composed of five female rats. All treatments were administered by intraperitoneal injection on the 5th, 10th, and 15th days of gestation. On the 20th day of gestation, 1 day prior to expected parturition, the rats were sacrificed by ether inhalation. The uterine horns and ovaries were surgically exposed to permit counting and recording of the numbers of corpora lutea, resorption sites, and viable and dead fetuses.The parameters resorptions, number of corpora lutea, fetal survival, mean fetal weight and gross, skeletal and visceral abnormalities were analysed. No increased level of fetal deaths was noted and no effect of teratogenicity was observed. Slight increase in gross and skeletal abnormalities was observed at concentrations above 119.89 mg/kg/day of the test chemical. The no observed adverse effect level (NOAEL) value of diisopropyl adipate was found at dose level of 119.89 mg/kg/day since at this dose no effects were observed on rat fetuses.

Developmental Toxicity Study 2:

A study equivalent and similar to Pre-Natal Developmental Toxicity study was performed to evaluate the effects of the test chemical on the maternal animals and their fetuses. In this study, the test chemical, was administered to the Wistar rats at the dose levels of 0, 2.9, 13.0, 62.0, or 288 mg/kg-day on GDs 6-15. Body weights were determined on gestation day (GD) 0, at one or two intervals before treatment ended, on the last day of hexanedioic acid treatment, and at terminal sacrifice. Appearance, behavior, and food consumption were evaluated daily. Two to 11 days after the final test chemical administration, pregnant animals were subjected to Caesarean section and the following parameters were recorded: implantation sites, resorption sites, and live and dead fetuses. A detailed examination of the urogenital tract of each pregnant female was performed, fetal weights of live pups were recorded, and a gross examination for external congenital abnormalities was performed on all fetuses (survival of neonatal rabbits was evaluated after placing live fetuses in an incubator for 24 hours). All surviving rabbit fetuses were dissected and examined for visceral abnormalities, then cleared, stained, and examined for skeletal defects. The test chemical treatment did not affect implantation of the conceptus into the uterus, maternal or fetal survival, or the incidence of soft tissue or skeletal tissue abnormalities. Thus, based on all the observations and the results, it was concluded that the NOAEL for the test chemical is considered to be 288 mg/kg bw.

Developmental Toxicity Study 3:

A study equivalent and similar to Pre-Natal Developmental Toxicity study was performed to evaluate the effects of the test chemical on the maternal animals and their fetuses. In this study, the test chemical, was administered to the CD-1 mice at the dose levels of 0, 2.6, 12, 56, 263 mg/kg-day on GDs 6-15. Body weights were determined on gestation day (GD) 0, at one or two intervals before treatment ended, on the last day of hexanedioic acid treatment, and at terminal sacrifice. Appearance, behavior, and food consumption were evaluated daily. Two to 11 days after the final test chemical administration, pregnant animals were subjected to Caesarean section and the following parameters were recorded: implantation sites, resorption sites, and live and dead fetuses. A detailed examination of the urogenital tract of each pregnant female was performed, fetal weights of live pups were recorded, and a gross examination for external congenital abnormalities was performed on all fetuses (survival of neonatal rabbits was evaluated after placing live fetuses in an incubator for 24 hours). All surviving rabbit fetuses were dissected and examined for visceral abnormalities, then cleared, stained, and examined for skeletal defects. The test chemical treatment did not affect implantation of the conceptus into the uterus, maternal or fetal survival, or the incidence of soft tissue or skeletal tissue abnormalities. Thus, based on all the observations and the results, it was concluded that the NOAEL for the test chemical is considered to be 263 mg/kg bw.

Developmental Toxicity Study 4:

A study equivalent and similar to Pre-Natal Developmental Toxicity study was performed to evaluate the effects of the test chemical on the maternal animals and their fetuses. In this study, the test chemical, was administered to the artificially inseminated Dutch-belted rabbits at the dose levels of 0, 2.9, 13.0, 62.0, or 288 mg/kg-day on GDs 6-15. Body weights were determined on gestation day (GD) 0, at one or two intervals before treatment ended, on the last day of hexanedioic acid treatment, and at terminal sacrifice. Appearance, behavior, and food consumption were evaluated daily. Two to 11 days after the final test chemical administration, pregnant animals were subjected to Caesarean section and the following parameters were recorded: implantation sites, resorption sites, and live and dead fetuses. A detailed examination of the urogenital tract of each pregnant female was performed, fetal weights of live pups were recorded, and a gross examination for external congenital abnormalities was performed on all fetuses (survival of neonatal rabbits was evaluated after placing live fetuses in an incubator for 24 hours). All surviving rabbit fetuses were dissected and examined for visceral abnormalities, then cleared, stained, and examined for skeletal defects. The test chemical treatment did not affect implantation of the conceptus into the uterus, maternal or fetal survival, or the incidence of soft tissue or skeletal tissue abnormalities. Thus, based on all the observations and the results, it was concluded that the NOAEL for the test chemical is considered to be 250 mg/kg bw.

Justification for classification or non-classification

Based on available data it can be concluded that the test chemical may not classified as toxic to reproduction as well as developmental toxicity according to CLP regulation.