Registration Dossier

Administrative data

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Additional information

Data from Vinyl Neodecanoate was read across to Vinyl Neononanoate due to structural similarity. The reproductive NOAEL from the rat oral gavage O.E.C.D. 422 screening study is 1000 mg/kg/day. Consumer exposure to Vinyl Neononanoate is not anticipated. Therefore, a consumer DNEL is not required. The O.E.C.D. 416 "Two-Generation Reproduction Toxicity Study" as per REACH Annex IX, Section 8.7.3 is proposed.


Short description of key information:
Data from Vinyl Neodecanoate was read across to Vinyl Neononanoate due to structural similarity. Vinyl Neodecanoate was evaluated in a GLP, O.E.C.D. 422 Combined repeated-dose, developmental/reproductive toxicity study by the oral gavage route of administration. Based on the findings from this study Vinyl Neodecanoate is not a reproductive toxicant or developmental in laboratory rats. The NOAEL for adult animals and reproductive/developmental effects was the high dose of 1000 mg/kg/day.

Effects on developmental toxicity

Description of key information
It is concluded from the lack of developmental effects seen in the OECD 414 rabbit developmental toxicity study and confounding effects of maternal toxicity seen in the OECD 414 rat study that vinyl neononanoate is not classified as a reproductive/developmental hazard.
Link to relevant study records

Referenceopen allclose all

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to O.ECc.D. test guideline 414 with GLP compliance.
Reference:
Composition 0
Qualifier:
according to
Guideline:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Deviations:
no
GLP compliance:
yes
Limit test:
no
Test material information:
Composition 1
Species:
rat
Strain:
Sprague-Dawley
Details on test animals and environmental conditions:
Sprague Dawley - Hsd:SD rats were acquired from Harlan Laboratories. Only female rats were assigned to the study; male rats were used for mating purposes only. The females were a minimum of 12 weeks old at the time of the initiation of the cohabitation period. At the initiation of the cohabitation period, females weighed 206-279 grams.

Upon arrival and until cohabitation, males were individually housed and females were group-housed, a maximum of five females per cage. During cohabitation, one or two females were placed with a male breeder. Following cohabitation, males and females were housed individually. Study animals were acclimated to their housing for 8 days prior to their first day of dosing.

The animal room was maintained at a temperature of 21.0 to 23.7°C and relative humidity of 43.9 to 65.8%. The light cycle within the animal room was set to maintain 12 hours light/12 hours dark. All animals had access to Harlan Teklad Rodent Diet (certified) or equivalent ad libitum. Water was available ad libitum to each animal via an automatic watering device.
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
The test substance formulations and control corn oil were administered to presumed pregnant females once daily beginning on the day of confirmed mating (Gestation Day 0) through presumed Gestation Day 19 inclusive. Each female rat received a daily total volume (ml) based on each animal’s most recent body weight and a dose volume of 4 ml/kg. Doses were administered using a 16-gauge stainless steel gavage needle attached to an appropriate size syringe. The test substance formulations and the corn oil vehicle were maintained on a stir plate during dose administration.
Analytical verification of doses or concentrations:
no
Details on mating procedure:
Animals were mated by placing one male and one or two females in a breeding cage until the females were determined to be Day 0 of gestation. This was determined by the examination of vaginal smears made daily to determine if sperm were present in a smear of vaginal contents or by the presence of a copulatory plug in situ.
Duration of treatment / exposure:
Once daily beginning on the day of confirmed mating (Gestation Day 0) and continuing through presumed Gestation Day 19 inclusive. Dose administration was performed at approximately the same time each day.
Frequency of treatment:
Once per day.
Duration of test:
Beginning on the day of confirmed mating (Gestation Day 0) and continuing through presumed Gestation Day 19 inclusive.
No. of animals per sex per dose:
24 females per group.
Control animals:
yes, concurrent vehicle
Details on study design:
All adult females were sacrificed by CO2 asphyxiation. Fetuses were euthanized by an intrathoracic injection of a barbiturate overdose. Surviving females were sacrificed on Day 20 of gestation. The uterus, ovaries and placenta, in addition to any gross lesions, were retained in 10% neutral buffered formalin. A complete gross necropsy was performed on all adult females assigned to study groups. The necropsy included the examination of the following:
• the external body surface
• all orifices
• the cranial, thoracic and abdominal cavities and their contents
Maternal examinations:
Mortality/morbidity was recorded twice daily (a.m. and p.m.). Animals were also observed for mortality/morbidity once prior to schedule sacrifice. During the treatment period (presumed Gestation Days 0 through19 inclusive), females were observed for clinical signs of toxicity a minimum of twice daily (prior to dose administration and a minimum of once post-dose – approximately 1-2 hours post-dose). Females were also observed prior to the scheduled cesarean on presumed Gestation Day 20.

Female body weights were collected during the treatment perio when each female was weighed on presumed Gestation Day 0 (after evidence of mating was observed and the female was assigned to a study group), on presumed Gestation Day 3 and on presumed Gestation Days 6 through 19 inclusive. On each scheduled occasion of body weight assessment, females were weighed prior to dose administration. Females were also weighed prior to the scheduled cesarean on presumed Gestation Day 20.

Feed Consumption was made whenfFull feeder weights and/or feeder weigh backs were recorded for each female for interval Days 0-3, 3-6, 6-9, 9-12, 12-15, 15-18 and 18-20 of gestation.

Ovaries and uterine content:
The uterus of each presumed pregnant female was excised, weighed and examined for early and late resorptions. The number of implantation sites and the number of viable and non-viable fetuses were recorded. The total number of corpora lutea were recorded for each ovary. Fetuses were examined externally, sexed and weighed Dead fetuses and early and late resorptions were placed in 10% neutral buffered formalin for possible histopathological evaluation. The uterus, ovaries and placenta, were retained in 10% neutral buffered formalin. The uterus were stained with 10% ammonium sulfide to assess the presence of implantation sites.
Fetal examinations:
Approximately 50% of fetuses determined to be viable were euthanized and an incision was made in the abdominal area of each of these fetuses prior to fixation to allow perfusion of the tissues. These fetuses were placed in 70% isopropyl alcohol for subsequent skeletal evaluation. The remaining fetuses determined to be viable were euthanized and were placed in Bouin’s fixative for subsequent whole body visceral evaluation using an adaptation of Wilson’s sectioning technique. Approximately one-half of the fetuses in each litter were eviscerated, cleared and examined for skeletal alterations after staining with alizarin red S.
Statistics:
Cesarean data were hand-tabulated and statistically evaluated using SYSTAT version 9.01 developed by SPSS, Inc. The number of early and late resorptions, the number of viable and nonviable fetuses, the total number of implantations sites, the number of corpora lutea per ovary and the percent of pre- and post-implantations losses were compared across groups using the Kruskal-Wallis non parametric ANOVA test. If a significant effect occurred (p<0.05), the Wilcoxon (Mann-Whitney U) test was used for pair-wise comparisons of each treated group to the control group. Male-to-female sex ratios were compared using the Chi-Square test.
Continuous data (fetal anomaly data) were analyzed using Bartlett’s Test of Homogeneity of Variances and the Analysis of Variance , when appropriate [i.e. Bartlett’s Test was not significant (p > 0.001)]. If the Analysis of Variance was significant (p ≤ 0.05), Dunnett’s Test was used to identify the statistical significance of the individual groups. If the Analysis of Variance was not appropriate [i.e. Bartlett’s Test is significant (p ≤ 0.001)], the Kruskal-Wallis Test was used (≤ 75% ties). In cases where the Kruskal-Wallis Test was statistically significant (p ≤ 0.05), Dunn’s Method of Multiple Comparisons was used to identify the statistical significance of the individual groups. If there were greater than 75% ties, Fisher’s Exact Test was used to analyze the data. Count data were evaluated using the procedures described above for the Kruskal-Wallis Test.7 Fetal alteration proportional data were analyzed using the Variance Test for Homogeneity of the Binomial Distribution.
Indices:
Male Sex Ratio, % Early Resorptions, % Late Resorptions, % Non-Viable Fetuses, % Pre-Implantation Loss and % Post-Implantation Loss
Historical control data:
No data
Details on maternal toxic effects:
Maternal toxic effects:yes

Details on maternal toxic effects:
Treatment-related clinical sign suggestive of neurotoxicity were recorded during the study for 71% of the high dose females (18 of 24 females) treated with 600 mg/kg/day of test substance. A combination of two or more of the following treatment-related signs were recorded for these 18 females: increased activity, hypersensitivity to sound and/or to touch, whole body tremors, twitching of the ears, an abnormal gait and/or stance. . None of these signs remained apparent from Gestation Day 8 onwards.
Dose descriptor:
NOAEL
Effect level:
ca. 300 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: maternal toxicity
Dose descriptor:
NOAEL
Effect level:
ca. 300 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: developmental toxicity
Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:yes

Details on embryotoxic / teratogenic effects:
The mean % early resorptions and % post-implantation loss of females treated with 600 mg/kg/day were statistically significantly increased (P < 0.01) 5-6-fold compared to the control female values. There was a reduced number of litters with viable fetuses (68% of litters compared to 100% of control litters) and an increased number of litters with nonviable fetuses (16% of litters compared to 5% of control litters). Reduced uteri weights and fetal body weights were also recorded for females treated with 600 mg/kg/day.
Dose descriptor:
NOAEL
Effect level:
300 mg/kg bw/day (actual dose received)
Sex:
male/female
Basis for effect level:
other: developmental toxicity
Abnormalities:
not specified
Developmental effects observed:
not specified

There were no adverse effects of the test substance on adult pregnant female body weight and feed consumption. There were no treatment-related gross necropsy findings observed on Gestation Day 20 for females treated with Vinyl neononanoate at doses of 100, 300 or 600 mg/kg/day. There were no treatment-related effects on any of the cesarean parameters examined for females treated with 100 or 300 mg/kg/day of test substance.

Conclusions:
The test substance, vinyl neononoanoate is a developmental toxicant in the rat at a maternally toxic dose of 600 mg/kg/day. This is based upon findings of statistically significant (P < 0.01) increased % early resorptions and % post-implantation fetal loss. Also, there wasa decrease in the mean number of viable fetuses relative to control value at the high dose of test substance. At the high dose of 600 mg/kg/day substantial maternal toxicity occured based on the observation of clinical signs of neurotoxicity in 71% of the animals. The maternal and embryo/fetal developmental NOAEL for this study is 300 mg/kg of maternal body weight.
Executive summary:

The test substance, vinyl neononoanoate was evaluated for the potential to cause developmental toxicity in an O.E.C.D. test guideline 414 study in the rat by the oral gavage route of exposure at dose levels of 0, 100, 300 and 600 mg/kg/day. The test substance, vinyl neononoanoate is a developmental toxicant in the rat at a maternally toxic dose level of 600 mg/kg/day. This is based upon findings of statistically significant (P < 0.01) increased % early resorptions and % post-implantation fetal loss at 600 mg/kg/day. Furthermore, a reduced number of litters with viable fetuses (68% of litters compared to 100% of control litters) and an increased number of litters with nonviable fetuses (16% of litters compared to 5% of control litters) was observed at the high dose level. Therefore, vinyl neononoanoate is a Reproductive toxicity Category 2, H361, "Suspected of damaging fertility or the unborn child."

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Reference:
Composition 0
Qualifier:
according to
Guideline:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Deviations:
no
GLP compliance:
yes
Limit test:
no
Test material information:
Composition 1
Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
Species: Rabbit
Stock: New Zealand White
Total Numbers: 80 females (4 groups of 20 females per group) and 24 male breeders
Gender: Female
Age Range: Females were approximately 6 to 7 months old at mating; records of dates of birth for animals used in this study are retained in the Calvert archives.
Body Weight Range: Male breeders weighed a minimum of 3.3 kg and mated females weighed a minimum of 3.4 kg
Animal Source: Covance Research Products Inc., 310 Swamp Bridge Road, Denver, PA 17517
Experimental History: Purpose-bred and experimentally na'ive at the outset of the study
Identification: Ear tag and cage card
Route of administration:
oral: gavage
Vehicle:
CMC (carboxymethyl cellulose)
Details on exposure:
Route: Oral via gavage, using a flexible feeding tube
Frequency: Animals were dosed once daily, beginning on Gestation Day 0 (day of confirmed mating) and continuing through presumed Gestation Day 28 inclusive. Dose administration was performed at approximately the same time each day (±4 hours from the previous day's dose times).
Procedure: The test substance formulations and vehicle control were administered to presumed pregnant females once daily, beginning on Gestation Day 0 (day of confirmed mating) and continuing through presumed Gestation Day 28 inclusive. The appropriate volume of formulation was withdrawn using chemicallyresistant syringes. The syringes were attached to a chemically-resistant stopcock. A 10 French flexible feeding tube was attached to the chemically-resistant stopcock, and was used to deliver the appropriate dose to each animal. Each animal received a daily total volume (ml) based on its most recent body weight and a dose volume of 5 mllkg. Following the dose, each animal immediately received a 5 ml flush of vehicle control. All formulations, including the vehicle control, were maintained on a stir plate during dose administration.


Analytical verification of doses or concentrations:
no
Details on mating procedure:
Mating was performed as outlined in Calvert's Standard Operating Procedure on natural breeding in rabbits. Evidence of mating determined Gestation Day 0 for each doe. Following mating, each doe was individually ear tagged with a unique animal number and was assigned to consecutive study groups. An effort was also made to avoid placing does mated to the same buck in the same study group Female rabbits were given the following identification numbers and identified by ear tag:

Group Number Females
1 1101-1120
2 1121-1140
3 1141-1160
4 1161-1180
Duration of treatment / exposure:
Animals were dosed once daily, beginning on Gestation Day 0 (day of confirmed mating) and continuing through presumed Gestation Day 28 inclusive. Dose administration was performed at approximately the same time each day (±4 hours from the previous day's dose times).
Frequency of treatment:
Once per day.
Duration of test:
Beginning on the day of confirmed mating (Gestation Day 0) and continuing through presumed Gestation Day 28 inclusive.
Dose / conc.:
0 mg/kg bw/day (actual dose received)
Dose / conc.:
30 mg/kg bw/day (actual dose received)
Dose / conc.:
300 mg/kg bw/day (actual dose received)
Dose / conc.:
600 mg/kg bw/day (actual dose received)
No. of animals per sex per dose:
20 females per group.
Control animals:
yes, concurrent vehicle
Details on study design:
The test substance, Vinyl neononanoate, was supplied by the Sponsor as a clear colorless liquid. The test substance was then prepared into dosing formulations for oral administration. Eighty experimentally na'lve New Zealand White female rabbits, a minimum of 6 months old and weighing 3.3 to 4.2 kg on the day of mating (deviations presented in Appendix IV), were assigned to treatment groups as outlined in the following table:

Group No./ Dose Level Concentration Dose Volume No. of
Treatment (mg/kg/day) (mg/ml) (ml/kg) Females*

Vehicle Control
(0.5% CMC/0.1 0 0 5 20
Tween 80)

Vinyl Neononanoate 30 6 5 20
Low Dose

Vinyl Neononanoate 300 60 5 20
Mid Dose

Vinyl Neononanoate 600 120 5 20
High Dose

* Twenty does were mated, in an attempt to ensure that a minimum of 16 does would be confirmed gravid during the cesarean section on presumed Day 29

Presumed pregnant females were dosed once daily beginning on the day of confirmed mating (presumed Gestation Day 0) through presumed Gestation Day 28 inclusive. Mortality/morbidity checks were performed twice daily during the gestation period. Females were also observed a minimum of twice daily (predose and one to two hours post-dose) during the gestation period. Females were weighed on Gestation Days 0 and 3 and daily from Gestation Days 6 through 29 inclusive. Food consumption was recorded daily for each female beginning on Gestation Day O. Surviving females were euthanized on presumed Gestation Day 29, and a complete gross necropsy, including the examination of the placenta, uterus and corpora lutea, was performed on each animal. The uterine weight, the total number of corpora lutea for each ovary, the total number of implantation sites, the number of early and late resorptions, and the number of viable and nonviable fetuses were also recorded. Each viable fetus was examined, weighed and sexed, and then euthanized. An examination of the viscera was performed on each fetus after euthanasia. Each fetus was then skinned and the carcass was placed in 99% alcohol for subsequent skeletal evaluation.
Maternal examinations:
Mortality/morbidity was recorded twice daily (a.m. and p.m.). Animals were also observed for mortality/morbidity once prior to schedule sacrifice. During the treatment period (presumed Gestation Days 0 through 28 inclusive), females were observed for clinical signs of toxicity a minimum of twice daily (prior to dose administration and a minimum of once post-dose – approximately 1-2 hours post-dose). Females were also observed prior to the scheduled cesarean on presumed Gestation Day 29.

Female body weights were collected during the treatment period when each female was weighed on presumed Gestation Day 0 (after evidence of mating was observed and the female was assigned to a study group), on presumed Gestation Day 3 and on presumed Gestation Days 6 through 28 inclusive. On each scheduled occasion of body weight assessment, females were weighed prior to dose administration. Females were also weighed prior to the scheduled cesarean on presumed Gestation Day 29.

Full feeder weights and/or feeder weigh backs were recorded daily for each female beginning on Geststion Day 0 for the assessment of food consumption.

Ovaries and uterine content:
The uterus of each presumed pregnant female was excised, weighed and examined for early and late resorptions. The number of implantation sites and the number of viable and non-viable fetuses were recorded. The total number of corpora lutea were recorded for each ovary. Fetuses will be individually identified by uterine location, examined externally and weighed. Dead fetuses will be placed in 10% neutral buffered formalin for possible histopathological evaluation. Photographs will be obtained for all fetal external malformations, and, for comparative purposes, representative photographs of control fetuses will also be obtained.

Each fetus will also be examined by dissection for visceral anomalies by using a modification of the microdissection technique, sexed, and the brain will be examined by mid-coronal section. Representative photographs of visceral abnormalities will be taken. After examination, each fetus will be skinned and the carcass will be fixed in 99% alcohol for subsequent skeletal evaluation.
Fetal examinations:
Approximately 50% of fetuses determined to be viable were euthanized and an incision was made in the abdominal area of each of these fetuses prior to fixation to allow perfusion of the tissues. These fetuses were placed in 70% isopropyl alcohol for subsequent skeletal evaluation. The remaining fetuses determined to be viable were euthanized and were placed in Bouin’s fixative for subsequent whole body visceral evaluation using an adaptation of Wilson’s sectioning technique. Approximately one-half of the fetuses in each litter were eviscerated, cleared and examined for skeletal alterations after staining with alizarin red S.
Statistics:
Cesarean data were hand-tabulated and statistically evaluated using SYSTAT version 9.01 developed by SPSS, Inc. The number of early and late resorptions, the number of viable and nonviable fetuses, the total number of implantations sites, the number of corpora lutea per ovary and the percent of pre- and post-implantations losses were compared across groups using the Kruskal-Wallis non parametric ANOVA test. If a significant effect occurred (p<0.05), the Wilcoxon (Mann-Whitney U) test was used for pair-wise comparisons of each treated group to the control group. Male-to-female sex ratios were compared using the Chi-Square test.
Continuous data (fetal anomaly data) were analyzed using Bartlett’s Test of Homogeneity of Variances and the Analysis of Variance , when appropriate [i.e. Bartlett’s Test was not significant (p > 0.001)]. If the Analysis of Variance was significant (p ≤ 0.05), Dunnett’s Test was used to identify the statistical significance of the individual groups. If the Analysis of Variance was not appropriate [i.e. Bartlett’s Test is significant (p ≤ 0.001)], the Kruskal-Wallis Test was used (≤ 75% ties). In cases where the Kruskal-Wallis Test was statistically significant (p ≤ 0.05), Dunn’s Method of Multiple Comparisons was used to identify the statistical significance of the individual groups. If there were greater than 75% ties, Fisher’s Exact Test was used to analyze the data. Count data were evaluated using the procedures described above for the Kruskal-Wallis Test.7 Fetal alteration proportional data were analyzed using the Variance Test for Homogeneity of the Binomial Distribution.
Indices:
Male Sex Ratio, % Early Resorptions, % Late Resorptions, % Non-Viable Fetuses, % Pre-Implantation Loss and % Post-Implantation Loss
Description (incidence and severity):
Clinical signs considered to be related to the administration of the test substance at 600 mg/kg/day consisted of scant feces, the absence of feces, the absence of urine, decreased activity and decreased muscle tone.
Dermal irritation (if dermal study):
no effects observed
Mortality:
mortality observed, treatment-related
Description (incidence):
Six adult females died prior to the scheduled cesarean on Gestation Day 29. Group 2 female No. 1131 (30 mg/kg/day) was found dead on Gestation Day 24. Group 3 female No. 1157 (300 mg/kg/day) was euthanized for humane reasons on Gestation Day 19. Group 4 female Nos. 1163, 1172, 1176 and 1177 (600 mg/kg/day) were euthanized for humane reasons on Gestation Days 15, 24, 19 and 19, respectively. The cause of death for Nos. 1131 and 1157 was determined to be a gavage error. The cause of death for the four high dose females (Nos. 1163, 1172, 1176 and 1177) was considered to be indicative of the adverse effects of Vinyl neononanoate at 600 mg/kg/day.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
A statistically significant mean weight loss was recorded for the 600 mg/kg/day dose group (– 0.06 kg) compared to the mean weight gain of the vehicle control group (0.04 kg) during the pre-implantation period (Gestation Days 0 – 6). Although not statistically significant, a lower mean weight gain was recorded for the 600 mg/kg/day group (0.03 kg) compared to the vehicle control group
(0.12 kg) during the fetal growth period (Gestation Days 19 – 29). The net result was a statistically significant lower mean weight gain during the entire gestation period (Gestation Days 0 – 29) for the 600 mg/kg/day group (0.12 kg) compared to the mean weight gain of the vehicle control group (0.30 kg) during the same period.
Description (incidence and severity):
There were no test substance-related effects on food consumption at the 30 and 300 mg/kg/day dose groups.
The mean daily food consumption of the 600 mg/kg/day dose group was lower than (with occasional statistical significance) the corresponding food consumption of the vehicle control group during the pre-implantation phase (Gestation Days 0 – 6) and the embryonic development phase (Gestation Days 6 – 19). During the fetal growth phase (Gestation Days 19 – 29), the mean daily food consumption of the 600 mg/kg/day group was generally comparable to the mean daily food consumption of the vehicle control group.
Description (incidence and severity):
There were no treatment-related gross necropsy findings observed on Gestation Day 29 for females treated with Vinyl neononanoate at doses of 30 300 mg/kg/day.
A cecum distended with gas, enlarged gallbladder, a hard and enlarged stomach filled with food and hair were observed for female No. 1167 treated with 600 mg/kg/day during the cesarean on Gestation Day 29. These necropsy findings were similar to those observed for the four females (Nos. 1163, 1172, 1176 and 1177) treated with 600 mg/kg/day euthanized early for humane reasons (refer to section 1. Adult Females Mortality/Morbidity above) and were considered to be related to the administration of the test substance at 600 mg/kg/day. Female No. 1167 also exhibited a prolonged reduced food consumption from Gestation Days 19 through 29 inclusive, and a correlating weight loss of 0.5 kg by Gestation Day 29.
Incidental findings observed during the cesarean on Gestation Day 29 consisted of a puncture wound in the right lower lung lobe of No. 1127 treated with 30 mg/kg/day. This finding was indicative of a gavage error, which most likely occurred on Gestation Day 28, since the animal’s food consumption was greatly reduced on Gestation Days 28 and 29. The liver of Female No. 1170 treated with 600 mg/kg/day had a mottled, pinkish gray pattern, which was asymmetrically and uniformly distributed throughout (nutmeg liver). The liver also penetrated throughout the parenchyma. This finding was also considered incidental, since a single animal in 600 mg/kg/day exhibited this finding.
Description (incidence and severity):
Signs of an abortion (the presence of a red substance and three fetuses on the cage tray paper) were noted for Group 4 female No. 1172 on Gestation Day 24. This animal was subsequently euthanized for humane reasons on Gestation Day 24, due to the abortion and a prolonged reduced food consumption and weight loss during the study. No other females exhibited signs of an abortion during the gestation period.
Description (incidence and severity):
There were no statistically significant differences in any of the cesarean parameters examined on this study for females treated with the test substance at 30, 300 or 600 mg/kg/day, when compared to the corresponding parameters of the vehicle control group.
Description (incidence and severity):
The pregnancy status was 90, 95, 85 and 90% for control females (Group 1), and females treated with 30 (Group 2), 300 (Group 3) and 600 (Group 4) mg/kg/day, respectively. Since adult females were dosed from Gestation Day 0 onwards on this study, the significance of the lower pregnancy rate recorded for Group 3 females is unclear. The administration of 300 mg/kg/day to adult females prior to implantation (Gestation Days 0 through 5 inclusive) could be indicative of an adverse effect on implantation. However, the pregnancy status for females treated with 600 mg/kg/day (90%) was comparable to the pregnancy status of control females, so the lower pregnancy status of females treated with 300 mg/kg/day was likely incidental and not related to treatment.
Dose descriptor:
NOAEL
Effect level:
300 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
clinical signs
mortality
other: maternal toxicity
Fetal body weight changes:
no effects observed
Description (incidence and severity):
Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): no effects observed
Reduction in number of live offspring:
no effects observed
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
no effects observed
Changes in postnatal survival:
no effects observed
External malformations:
no effects observed
Description (incidence and severity):
There were no test substance-related external malformations or variations at any dose level.
Skeletal malformations:
no effects observed
Description (incidence and severity):
There were no test substance-related skeletal malformations or variations at any dose level.
Visceral malformations:
no effects observed
Description (incidence and severity):
There were no test substance-related soft tissue malformations or variations at any dose level.
Dose descriptor:
NOAEL
Effect level:
300 mg/kg bw/day (actual dose received)
Sex:
male/female
Basis for effect level:
other: maternal toxicity induced
Abnormalities:
not specified
Developmental effects observed:
not specified

The purpose of this study was to assess the potential adverse effects of Vinyl Neononanoate on the pregnant female rabbit and on the development of the embryo and fetus consequent to exposure of the female, from mating (presumed Gestation Day 0) through the gestation period (presumed Gestation Day 29).

This study was conducted in compliance with the appropriate OECD Principles of Good Laboratory Practice [C(97)186/Final], and also allows for submission of the report under the Mutual Acceptance of Data (MAD) agreement with applicable OECD member countries.

Conclusions:
No exposure-related teratogenicity was observed at doses of ≤ 600 mg/kg/day.
Executive summary:

Female New Zealand White rabbits received Vinyl neononanoate orally once daily, at a dose of 30, 300 or 600 mg/kg/day, from Gestation Days 0 through 28 inclusive.

One female at 30 mg/kg/day was found dead and one female at 300 mg/kg/day was euthanized for humane reasons during the study. The cause of death for both animals was a punctured lung resulting from a gavage error. One abortion occurred on Gestation Day 24 for the 600 mg/kg/day dose group. A total of four females treated with 600 mg/kg/day were euthanized prior to the scheduled cesarean on Gestation Days 29, due to a prolonged reduced food consumption and associated weight loss (0.4 to 0.6 kg for each animal).

There were no treatment-related clinical signs at doses of 30 or 300 mg/kg/day. At 600 mg/kg/day, treatment-related clinical signs included the presence of scant feces, the absence of feces, the absence of urine, decreased activity and decreased muscle tone for several animals during the study.

There were no treatment-related effects on body weight at doses of 30 or 300 mg/kg/day. A mean weight loss was recorded during the pre-implantation period (Gestation Days 0 – 6) and a reduced mean weight gain was recorded during the fetal growth period (Gestation Days 19 – 29) for the 600 mg/kg/day dose group. The overall mean body weight of females treated with 600 mg/kg/day was statistically significantly lower than the mean body weight of vehicle control females on Gestation Day 29.

There were no treatment-related effects on food consumption at doses of 30 or 300 mg/kg/day. Reduced mean food consumption was recorded during the pre-implantation phase (Gestation Days 0 – 6) and the embryonic development phase (Gestation Days 6 – 19) for the 600 mg/kg/day dose group.

There were no gross lesions considered to be related to doses of 30 or 300 mg/kg/day. Gross findings and gross lesions observed for the 600 mg/kg/day dose group consisted of a cecum distended with gas, enlarged gallbladder, a hard and enlarged stomach filled with food and hair. A combination of these gross necropsy findings occurred in one female euthanized at the scheduled cesarean on Gestation Day 29, and in four other females that were euthanized for humane reasons during the study.

The pregnancy status was 90, 95, 85 and 90% for control females (Group 1), and females treated with 30 (Group 2), 300 (Group 3) and 600 (Group 4) mg/kg/day, respectively. The lower pregnancy status of females treated with 300 mg/kg/day was likely incidental and not related to treatment.

There were no statistically significant differences in any of the cesarean parameters for doses of 30, 300 or 600 mg/kg/day. However, the mean number of early resorptions (both fetal and litter incidences) and % early resorptions for females treated with 30, 300 and 600 mg/kg/day were higher than those of vehicle control females. The mean fetal incidences of early resorptions were 0.7, 0.4 and 0.6 for the 30, 300 and 600 mg/kg/day dose groups, respectively, compared to 0.2 for the vehicle control group. The mean litter incidences of early resorptions were 27.8%, 25.0% and 35.7% for the 30, 300 and 600 mg/kg/day dose groups, respectively, compared to 5.6% for the vehicle control group. Additionally, the mean uterus weight of females treated with 600 mg/kg/day was approximately 18% lower than the mean uterus weight of vehicle control females, due to the slightly lower number of mean viable fetuses for the 600 mg/kg/day dose group (7.1) compared to the vehicle control group (8.6).

There were no treatment-related fetal external, soft tissue or skeletal abnormalities (malformations or variations) at 30, 300 or 600 mg/kg/day.

Based on the above findings observed for the adult female at 600 mg/kg/day, which consisted primarily of reduced food consumption, reduced weight gain and subsequent euthanasia of several animals, No-Observed-Adverse-Effect-Level (NOAEL) for maternal exposure was considered to be 300 mg/kg/day. Since the fetal and litter incidences of increased early resorptions at doses of 30, 300 or 600 mg/kg/day were not statistically significant, the NOAEL for embryofetal development was also considered to be 300 mg/kg/day. No exposure-related teratogenicity was observed at doses of600 mg/kg/day.

Effect on developmental toxicity: via oral route
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEL
300 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
High
Additional information

The test substance, vinyl neononoanoate was evaluated for the potential to cause developmental toxicity in an O.E.C.D. test guideline 414 study in the rat by the oral gavage route of exposure at dose levels of 0, 100, 300 and 600 mg/kg/day. The test substance, vinyl neononoanoate is a developmental toxicant in the rat at a matrnally toxic dose of 600 mg/kg/day. This is based upon findings of statistically significant (P < 0.01) increased % early resorptions and % post-implantation fetal loss, and decreased number of viable fetuses relative to control at the high dose level of 600 mg/kg/day. Substantial maternal toxicity was observed at 600 mg/kg/day basd upon clinical signs of neurotoxicty in 71% of the high dose animals. The maternal and embryo/fetal developmental NOAEL for this study was 300 mg/kg/day.

In this study all litters that showed more than 3 early resorptions were from dams that showed clinical signs of neurotoxicity including hypersensitivity, in many cases increased activity and in some cases abnormal gait and or tremors, either during or just before the time of implantation (typically GD 5-6 in Sprague-Dawley rats). The frequency of these signs and the fact one high dose female was sacrificed moribund due to severity leads to the conclusion that maternal toxicity at the high dose was excessive, confounding interpretation of any specific developmental toxicity. These maternal observations were made despite the absence of formal out-of- cage assessments of clinical signs or motor activity, which might have more clearly characterized the extent of neurotoxic signs. Autonomic nervous system parameters were not evaluated, although increased body temperature and heart rate are commonly seen with increased activity (Roche et al., 2007); as noted above increased activity was documented for a number of dams at 600 mg/kg bw/day during the pre-implantation period. Any of the hypothetical autonomic system effects resulting from maternal neurotoxicity could have adverse effects on embryo survival and/or successful implantation. Only a 1.5°C elevation of temperature above normal core temperature, during the pre-implantation period, can result in increased rates of embryonic death and resorption in a wide range of species (Bell, 1987).

Hood and Miller (2006) state there is little evidence generally for correlation between excessive maternal toxicity and specific fetal malformations. However, there seems to be more evidence that maternal toxicity can lead to decreased fetal weight and decreased ossification sites (Chernoff et al., 2008); minimal effects on both parameters were seen in the current study at the maternally toxic high dose. There is relatively little in the published literature relating to the relationship between maternal toxicity and early resorptions, although it is a reasonable supposition that this absence of literature may be due to the fact that many developmental toxicity evaluations are conducted during the period of major organogenesis starting at GD 6 after implantation is complete. (The OECD Guideline, in contrast, recommends dosing from GD 0 based on the presence of sperm in vaginal lavage or a sperm plug.) Interference with implantation can contribute to an increase in early resorptions. Alternatively increased maternal temperature, or other maternal autonomic nervous system changes hypothesized in the current study based on maternal clinical signs, may lead to embryonic or fetal mortality, resulting in resorption of implanted or implanting tissue.

In the absence of mechanistic data it is not possible to definitively ascribe the developmental toxicity seen in this study to maternal toxicity for classification purposes, which is consistent with the conclusions regarding classification based on maternal toxicity in Bayer et al. ( 2011). Clearly excessive maternal toxicity and the developmental toxicity were seen at the same exposure level in this study, and the severity of effects appears consistent, with a maternal moribund sacrifice and in some cases severe clinical signs of neurotoxicity correlating with increased early post implantation loss. Bayer et al. (2011) indicates that many classification decisions hinge on the relative severity of maternal and developmental effects; in this case they appear equally severe. The data suggest that the developmental toxicity would be unlikely to be seen in the absence of maternal toxicity, and a robust maternal and developmental NOAEL at a relatively high exposure level of 300 mg/kg bw/day throughout gestation is available for risk assessment.

 

Bell, A.W. (1987) Consequences of severe heat stress for fetal development. In: Heat Stress: Physical Exertion and Environment. J.R.S. Hales and D.A.B. Richards, eds. Amsterdam:Exerpta Medica, Elsevier Science, pp. 313–333.

Beyer, B.K., Chernoff, N., Bengt, R., Danielsson, K.D., Harrouk, W., Hood, R.D., Janer, G., Liminga, U., Kim, J.H., Rocca, M., Rogers, J. and Scialli, A.R. (2011) ILSI/HESI Maternal Toxicity Workshop Summary: Maternal Toxicity and Its Impact on Study Design and Data Interpretation.Birth Defects Research(Part B) 92:36–51

Chernoff, N., Rogers, E.H., Gage, M.I., Francis, B.M. (2008) The relationship of maternal and fetal toxicology bioassays with notes on the biological significance of the ‘‘no observed adverse effect level’’.Reprod Toxicol25:192–202.

Hood, R.D., Miller, D.B. (2006) Maternally mediated effects on development. In: Hood RD, editor. Developmental and reproductive toxicology, a practical approach. 2nd ed. Boca Raton: CRC Press. p 93–124.

Roche, M., Harkin A., .Kelly, J.P. (2007) Chronic Fluoxetine Treatment Attenuates Stressor-Induced Changes in Temperature, Heart Rate, and Neuronal Activation in the Olfactory Bulbectomized RatNeuropsychopharmacology

Female New Zealand White rabbits received Vinyl neononanoate orally once daily, at a dose of 30, 300 or 600 mg/kg/day, from Gestation Days 0 through 28 inclusive.Based on the above findings observed for the adult female at 600 mg/kg/day, which consisted primarily of reduced food consumption, reduced weight gain and subsequent euthanasia of several animals, No-Observed-Adverse-Effect-Level (NOAEL) for maternal exposure was considered to be 300 mg/kg/day. Since the fetal and litter incidences of increased early resorptions at doses of 30, 300 or 600 mg/kg/day were not statistically significant, the NOAEL for embryofetal development was also considered to be 300 mg/kg/day. No exposure-related teratogenicity was observed at doses of600 mg/kg/day.


Justification for classification or non-classification

Based on the available data, Vinyl Neononanoate does not meet the criteria for Classification and Labeling as a Substance toxic to reproduction as per EU Directive 67/548/EEC Annex 6 and the CLP (Directive 1272/2008).