Isopropenyl acetate

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on test type (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD Guideline study report

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Isopropenyl acetate

EC Number:

203-562-7

EC Name:

Isopropenyl acetate

Cas Number:

108-22-5

Molecular formula:

C5H8O2

IUPAC Name:

isopropenyl acetate

Details on test material:

Identification: Isopropenyl acetate
Test Item Name for Report: Isopropenyl acetate
Chemical Name: 1-Propen-2-ol, acetate
CAS Number 108-22-5
Description: liquid, colorless
Stability of Test Item in Vehicle: 7 days
Storage Conditions: Room temperature (20 ±5 °C)
Safety Precautions: Routine hygienic procedures (gloves, goggles, face
mask).

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Animals: Rat, HanRcc: WIST(SPF)
Rationale: Recognized by international guidelines as a recommended test system.
Breeder: Harlan Laboratories Ltd., Laboratory Animal Services, Wölferstrasse 4, 4414 Füllinsdorf / Switzerland
Number of Animals: 40 males: 10 per group; 40 females: 10 per group
Age (at Start of Treatment): 11 weeks
Body Weight Range(at Start of Treatment):Males: 284 to 326 g; Females: 187 to 223 g
Identification: Cage card and individual animal number (ear tattoo).
Randomization: Computer-generated random algorithm. In addition body weights (recorded on the day of allocation were taken into consideration in order to ensure similar mean body weights in all groups.
Acclimatization: Under test conditions after health examination. Only animals without any visible signs of illness were used for the study.

Conditions: Standard laboratory conditions. Air-conditioned with 10 - 15 air changes per hour, continuously monitored environmental conditions (temp. range: 22 ± 3 °C; relative humidity range: 30 - 70%). There was 12-hour fluorescent light / 12-hour dark cycle with music during the light period.
Accommodation: Individually in Makrolon type-3 cages with wire mesh tops and sterilized standard softwood bedding (‘Lignocel’J. Rettenmaier & Söhne GmbH & CoKG, 73494 Rosenberg / Germany, imported by Provimi Kliba SA, 4303 Kaiseraugst / Switzerland, ). During the pre-pairing period, cages with males were interspersed amongst those holding females to promote the development of regular estrus cycles.
Diet: Pelleted standard Kliba Nafag 3433 (batch no. 15/09) rodent maintenance diet (Provimi Kliba SA, 4303 Kaiseraugst / Switzerland) was available ad libitum.
Water: Community tap-water from Füllinsdorf was available ad libitum in water bottles.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: weekly


DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): vehicle
- Storage temperature of food: room temperature (20 ± 5 °C) in glass beakers


VEHICLE
- Justification for use and choice of vehicle (if other than water): solubility and non-toxicity
- Concentration in vehicle: to ensure a dose volume of 5 mL/kg body weight
- Amount of vehicle (if gavage): 5 mL/kg body weight
- Lot/batch no. (if required): 37899577
- Purity: not given

Details on mating procedure:

During the pairing period, females were housed with sexually mature males (1:1) in special
automatic mating cages i.e. with synchronized timing to initiate the nightly mating period, until
evidence of copulation was observed. This system reduced the variation in the copulation times
of the different females. The females were removed and housed individually if:
- the daily vaginal smear was sperm positive, or
- a copulation plug was observed.
The day of mating was designated day 0 post coitum.
All dams were allowed to give birth and rear their litters (F1 pups) up to day 4 post partum.
Day 0 was designated as the day on which a female had delivered all her pups.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The samples received were dissolved in acetone by sonication for 5 minutes and then diluted to volume with dilution solvent. The sample solutions were further diluted with dilution solvent into the calibration range.
GC: AGILENT 6890
Column: VF 5 MS Varian, 30 m x 0.25 mm, 1.0 μm film thickness
Carrier Gas: Helium, 1.0 mL/min, constant flow
Injection: 1 μL, splitless
Detector: FID
Temperatures: Injector: 250 °C
Detector: 325 °C
Oven: 40 °C for 1 min at 10 °C/min to 100 °C
100 °C for 0 min at 30 °C/min to 300 °C
300 °C for 5 min

Duration of treatment / exposure:

28 days (males), 49 days (females)

Frequency of treatment:

once daily

Details on study schedule:

not applicable

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 50, 200 and 1000 mg/kg bw
Basis:
nominal conc.

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Pretest with the same concentrations
- Rationale for animal assignment (if not random): random

Positive control:

not applicable

Examinations

Parental animals: Observations and examinations:

Viability / Mortality: Twice daily
Clinical Signs: Daily cage-side clinical observations (once daily, during acclimatization and up to day of necropsy). Additionally females were observed for signs of difficult or prolonged parturition, and behavioral abnormalities in nesting and nursing.
Food Consumption: Males: Weekly during pre-pairing and after pairing periods.
Females: Pre-pairing period days 1 - 8 and 8 - 14 of the pre-pairing period; gestation days 0 - 7, 7 - 14 and 14 - 21 post coitum, and days 1 - 4 post partum. No food consumption was recorded during the pairing period.
Body Weights: Recorded daily from treatment start to day of necropsy.

Oestrous cyclicity (parental animals):

not reported

Sperm parameters (parental animals):

Parameters examined in [P] male parental generations:
[testis weight, epididymis weight]

Litter observations:

Pup Data: The litters were examined for litter size, live births, still births and any gross anomalies. The sex ratio of the pups was recorded. Pups were weighed individually (without identification) on days 0 (if possible), 1 and 4 post partum.

Postmortem examinations (parental animals):

All parent animals and pups were examined macroscopically for any structural changes, either at the scheduled necropsy or during the study if death occurred.
For the parent animals, special attention was directed to the organs of the reproductive system. The number of implantation sites and corpora lutea was recorded for all dams with litters. The uteri of non-pregnant females were placed in a solution of ammonium sulfide to visualize possible hemorrhagic areas of implantation sites

The testes and epididymides of all parental males were weighed as pairs.

Postmortem examinations (offspring):

Dead pups, except those excessively cannibalized, were examined macroscopically.

Statistics:

The following statistical methods were used to analyze food consumption, body weights and
reproduction data:
• Means and standard deviations of various data were calculated.
• The Dunnett-test (many to one t-test) based on a pooled variance
estimate was applied if the variables could be assumed to follow a normal distribution
for the comparison of the treated groups and the control groups for each sex.
• The Steel-test (many-one rank test) was applied instead of the
Dunnett-test when the data could not be assumed to follow a normal distribution.
• Fisher's exact-test was applied if the variables could be
dichotomized without loss of information.

Reproductive indices:

From the on-line recorded reproduction data, the following parameters were calculated: fertility indices, mean precoital time, post-implantation losses, mean litter size, pup sex ratios and viability indices.

Offspring viability indices:

For reproduction data, group mean values were calculated both on a litter basis and on a percentage per group basis. Mean pup weights were calculated from the individual weights both on a per group and on a per litter basis.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

no effects observed

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

Details on results (P0)

General Tolerability
No deaths occurred before scheduled termination. No test item-related adverse clinical signs were observed during the study at any dose level.
At the dose levels of 200 and 1000 mg/kg/day, salivation was observed in males and females. This observation was considered to be a sign of discomfort caused by the test item but not an adverse effect.

Food Consumption
Food consumption was not affected by the treatment with the test item at any dose level neither in males nor in females.

Body Weights
Body weights and body weight gain were not affected by the treatment with the test item at any dose level neither in males nor in females.

Reproduction and Breeding Data
Except for one female at the dose level of 50 mg/kg/day, all females were mated, became pregnant and gave birth. Mating performance, fertility, gestation and parturition were not affected by the treatment with the test item at any dose level.

Organ Weights
Weights of testes and epididymides were not affected by the treatment with the test item at any dose level.

Macroscopical Findings and Histopathological Examinations
No gross lesions attributed to treatment with the test item were noted at any dose level. No test item-related histopathology findings were noted neither in males nor in females treated with the test item at the highest dose. No test item-related histopathology findings were noted during examination of reproductive organs of female which did not become pregnant and its male partner at the dose level of 50 mg/kg/day.

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

other: salviation in 200 and 1000 mg/kg bw group

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings:

no effects observed

Details on results (F1)

Litter Size at First Litter Check and Postnatal Loss During Lactation
Number of pups at first litter check and viability of pups up to day 4 post partum were considered not to be affected by the treatment with the test item at any dose level. Sex ratios at first litter check and on day 4 post partum were considered not to be affected by the treatment with the test item at any dose level.

Findings at First Litter Check and during Lactation
No abnormal findings were noted at first litter check and during the first 4 days post partum at any dose level.

Pup Weights to Day 4 Post Partum
Pups body weights and body weight gain to day 4 post partum were not affected by the treatment with the test item at any dose level.

Macroscopical Findings
No findings were noted at macroscopic examination of pups at any dose level.

Effect levels (F1)

Dose descriptor:

NOEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

other: overall effects

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Study Sequence	Females	Males
Acclimatization	7 days minimum	7 days minimum
First Test Item Administration	Day 1 of pre-pairing	Day 1 of pre-pairing
Pre-Pairing	14 days	14 days
Pairing	14 days maximum	14 days maximum
Gestation	Approximately 21 days	-
Treatment Ends	On day 3 post partum	On day before sacrifice
Necropsy	On day 4 post partum	After 28 days of treatment

Applicant's summary and conclusion

Conclusions:

No effects on for reproduction/development of rats were noticed up to the highest concentration tested of 1000 mg/kg bw.

Executive summary:

Isopropenyl acetate (purity 99.3%) was administered to male rats for 28 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 pups reached day 4 post partum according to OECD Guideline 421. The following dose levels were applied: 0 (control group), 50, 200 and 1000 mg/kg body weight/day. A standard dose volume of 5 mL/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (corn oil).

No deaths occurred in parent animals before scheduled termination. No test item-related adverse clinical signs were observed during the study at any dose level. At the dose levels of 200 and 1000 mg/kg/day, salivation was observed in males and females. This observation was considered to be a sign of discomfort caused by the test item but not an adverse effect. Food consumption was not affected by the treatment with the test item at any dose level neither in males nor in females. Body weights and body weight gain were not affected by the treatment with the test item at any dose level neither in males nor in females. Except for one female at the dose level of 50 mg/kg/day, all females were mated, became pregnant and gave birth. Mating performance, fertility, gestation and parturition were not affected by the treatment with the test item at any dose level. Weights of testes and epididymides were not affected by the treatment with the test item at any dose level. No gross lesions attributed to treatment with the test item were noted at any dose level. No test item-related histopathology findings were noted neither in males nor in females treated with the test item at the highest dose. No test item-related histopathology findings were noted during examination of reproductive organs of female which did not become pregnant and its male partner at the dose level of 50 mg/kg/day.

Number of pups at first litter check and viability of pups up to day 4 post partum were considered not to be affected by the treatment with the test item at any dose level. Sex ratios at first litter check and on day 4 post partum were considered not to be affected by the treatment with the test item at any dose level. No abnormal findings were noted at first litter check and during the first 4 days post partum at any dose level. Pups body weights and body weight gain to day 4 post partum were not affected by the treatment with the test item at any dose level. No findings were noted at macroscopic examination of pups at any dose level.

Under the conditions described for this study, the general NOAEL (No Observed Adverse Effect Level) for parental organism was considered to be 1000 mg/kg body weight/day. The NOEL (No Observed Effect Level) for reproduction/developmental toxicity was considered to be 1000 mg/kg body weight/day.