3-methyl-1-vinyl-1H-imidazolium chloride

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on test type (migrated information)

Type of information:

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

Adequacy of study:

key study

Study period:

2012-02-09 and 2013-05-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-conform study in accordance to OECD guideline and US EPA guideline. The test substance analogue was used. For read-across justification, please refer to section 13.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650 (Combined Repeated Dose Toxicity Study With the Reproduction/Developmental Toxicity Screening Test) 2000

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

3-methyl-1-vinyl-1H-imidazolium methyl sulphate

EC Number:

247-832-2

EC Name:

3-methyl-1-vinyl-1H-imidazolium methyl sulphate

Cas Number:

26591-72-0

Molecular formula:

C6H9N2.CH3O4S

IUPAC Name:

3-methyl-1-vinyl-2,3-dihydro-1H-imidazol-1-ium methyl sulfate

Test material form:

other: powder

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH
- Age at study initiation: 12-13 weeks
- Weight at study initiation: F0 generation: male animals: 339.0 g - 372.4 g, female animals: 191.1 g - 225.1 g
- Housing:
Individually in Makrolon type M III cages, with the following exceptions: a) During overnight matings, male and female mating partners were housed together in Makrolon type M III cages. b) Pregnant animals and their litters were housed together until PND 4.
- Diet: ad libitum, Kliba maintenance diet mouse/rat “GLP” meal (Provimi Kliba SA, Kaiseraugst, Switzerland)
- Water: ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: For the preparation of the administration solutions the test substance was weighed in a calibrated beaker depending on the dose group, topped up with drinking water and subsequently intensely mixed with a magnetic stirrer until it was completely dissolved. The analytical results indicated that the test substance is stable in drinking water over a period of 7 days.

DIET PREPARATION
- Rate of preparation of diet (frequency): at the beginning of the administration period and thereafter in intervals

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: overnight for a maximum of two weeks
- Proof of pregnancy: vaginal smear referred to as day 0 of pregnancy
- After successful mating each pregnant female was caged: individually
- Any other deviations from standard protocol: none

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The sample preparation were analytically verified by using HPLC method coupled with a DAD. Therefore, approx. 0.05 g of the test substance was dissolved to 100 mL usind drinking water. All determined concentrations were in the range between 90% and 110% of the nominal concentration, demonstrationg the correctness of the preparations.

Duration of treatment / exposure:

females: 49 days
males: 34 days

Frequency of treatment:

once daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 100, 300, 1000 mg/kg bw/d
Basis:
nominal in water

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Positive control:

not applicable

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: at least once daily
- Cage side observations checked: any signs of morbidity, pertinent behavioral changes and signs of overt toxicity
- The parturition and lactation behavior of the dams was generally evaluated in the mornings in combination with the daily clinical inspection of the dams. Only particular findings (e.g. inability to deliver) were documented on an individual dam basis.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once prior to the first administration and at weekly intervals during the administration period

BODY WEIGHT: Yes
- Time schedule for examinations: once a week
- The following exceptions are notable for the female animals:
a) During the mating period the parental females were weighed on the day of positive evidence of sperm (gestation day 0) and on gestation days 7, 14 and 20.
b) Females with litter were weighed on the day of parturition (postnatal day 0) and on postnatal day 4.

FOOD CONSUMPTION: Yes
- once a week
- Exceptions:
a) Food consumption was not determined after the 2nd premating week (male parental animals) and during the mating period (male and female F0 animals).
b) Food consumption of the F0 females with evidence of sperm was determined on gestation days (GD) 0, 7, 14 and 20.
c) Food consumption of F0 females, which gave birth to a litter was determined on postnatal day 1
and 4.

WATER CONSUMPTION: not examined

OTHER: Haematology, clinical chemistry, urinalysis, neurobehavioural examination

Oestrous cyclicity (parental animals):

A vaginal smear was prepared after each mating and examined for the presence of sperm.

Sperm parameters (parental animals):

Parameters examined in male parental generations:
testis weight, epididymis weight

Litter observations:

STANDARDISATION OF LITTERS
- The pups were sexed and examined for macroscopically evident changes on postnatal day 0.
- They were weighed on postnatal day 1 and on postnatal day 4.

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
[number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain

GROSS EXAMINATION OF DEAD PUPS:
Yes, for external and internal abnormalities; possible cause of death was not determined for pups born or found dead.

Postmortem examinations (parental animals):

SACRIFICE
- The female animals were sacrificed 49 days after the beginning of the administration.
- The male animals were sacrificed 34 days after the beginning of the administration.

GROSS NECROPSY
- adrenal glands, aorta, bone marrow (femur), brain, cecum, cervix, coagulating gland, colon, duodenum, eyes with optic nerve, esophagus, extraorbital lacrimal glands, epididymides, femur with knee joint, heart, ileum, jejunum, kidneys, larynx, liver, lungs, lymph nodes, mammary gland, nose, ovaries, oviducts, pancreas, parathyroid glands, pharynx, pituitary gland, prostate gland, rectum, salivary glands, sciatic nerve, seminal vesicles, skeletal muscle, spinal cord, spleen, sternum with marrow, stomach, testes, thymus, thyroid, glands, trachea, urinary bladder, uterus, vagina

HISTOPATHOLOGY / ORGAN WEIGHTS
The following tissues were prepared for microscopic examination: adrenal glands, all gross lesions, bone marrow (femur), brain, cecum, cervix, coagulating glands, colon, duodenum, epididymes, heart, ileum, jejunum, kidneys, liver, lungs, lymph nodes, ovaries, oviducts, prostate gland, peyer's patches, rectum, sciatic nerve, seminal vesicles. The following organs were weighed: Epididymides, testes (in all animals sacrificed); adrenal glands, brain, heart, kidneys, liver, spleen, thymus (in 5 animals per sex/test group, females with litters only, same animals as used for clinical pathological examinations)

Postmortem examinations (offspring):

SACRIFICE
- Pups were sacrificed under isoflurane anesthesia with CO2 on day 4 of parturition.

NECROPSY
- All pups were examined externally and eviscerated; their organs were assessed macroscopically.

Statistics:

The following statistical tests were used (depending on the parameter): DUNNETT-test, KRUSKAL-WALLIS test, WILCOXON-test (one-side)

Reproductive indices:

male mating index (%), male fertility index (%), female mating index (%), female fertility index (%), gestation index (%), postimplantation loss (%)

Offspring viability indices:

Viability index (%), live birth index (%)

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

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:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Other effects:

not examined

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)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS):
No clinical signs or changes of general behavior, which may be attributed to the test substance, were detected in any male or female. Several male and female animals of dose group 3 (1000 mg/kg bw/d) showed salivation after treatment. This transient salivation for a few minutes immediately after each treatment was likely to be induced by the unpleasant taste of the test substance or by local irritation of the upper digestive tract. It is not considered to be a sign of systemic toxicity. There were no substance-related mortalities in any of the male and female parental animals in any of the groups. On premating day 12, one high dose F0 female (No. 137 - 1000 mg/kg body weight/day) was found dead after a gavage error.
BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS): Not affected.The fertility index varied between 88.9 % in test groups 3 and 1 and 100% in test group 2 and in control. These values reflect the normal range of biological variation inherent in the strain of rats used for this study. The gestation index was 100% in control and all dose groups.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS): Not affected. The male fertility index ranged between 80% and 100% without showing any relation to dosing.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS): No test substance-related adverse findings

ORGAN WEIGHTS (PARENTAL ANIMALS): When compared to the control group 0 (set to 100%), the mean relative and absolute liver weight was significantly increased in male animals of the high-dose group. All other mean relative and absolute weight parameters in males and all weight parameters in females did not show significant differences when compared to the control group 0. The increase in absolute and relative liver weights in test group 3 (1000 mg/kg bw/day) in male animals was considered to be treatment - related.

GROSS PATHOLOGY (PARENTAL ANIMALS): One female animal that died showed a ruptured esophagus. All other findings occurred individually. They were considered to be incidental or spontaneous in origin and without any relation to treatment.

HISTOPATHOLOGY (PARENTAL ANIMALS): One animal showed rupture of the esophagus confirming the macroscopic diagnosis. All other findings occurred either individually or were biologically equally distributed over control and treatment groups. They were considered to be incidental or spontaneous in origin and without any relation to treatment.

Effect levels (P0)

1

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: reproductive performance and fertility

2

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: general, systemic toxicity

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:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Details on results (F1)

VIABILITY (OFFSPRING): The viability index indicating pup mortality during lactation (postnatal day 0 - 4) varied between 86.4% (1000 mg/kg bw/d), 100% (100 and 300 mg/kg bw/d) and 99.2% (control) without showing any association to the treatment.

CLINICAL SIGNS (OFFSPRING): There were no test substance-related adverse clinical signs observed in any of the F1 generation pups of the different test groups.

BODY WEIGHT (OFFSPRING): No test compound-related influence on F1 pup body weights and pup body weight change were noted in all dose groups. Two male runts were seen in test group 3 (1000 mg/kg bw/d). This incidence was considered as spontaneous in nature and not treatment related.

SEX DISTRIBUTION (OFFSPRING): The sex distribution and sex ratios of live F1 pups on the day of birth and postnatal day 4 did not show substantial differences between the control and the test substance-treated groups; slight differences were regarded to be spontaneous in nature.

GROSS PATHOLOGY (OFFSPRING): A few pups showed spontaneous findings at gross necropsy, such as post mortem autolysis, situs inversus, reddish discolored testis, hydroureter and hydronephrosis. Thus, all these findings were not considered to be associated to the test substance.

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: developmental toxicity

Overall reproductive toxicity

Reproductive effects observed:

not specified

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