α,α,α-trifluoro-4-nitro-m-cresol

Toxicity to reproduction

Administrative data

Endpoint:

three-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

other information

Study period:

1971 to 1973

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1973

Reference 2

Reference Type:

review article or handbook

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Version / remarks:

2001-01-22

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

α,α,α-trifluoro-4-nitro-m-cresol

EC Number:

201-818-2

EC Name:

α,α,α-trifluoro-4-nitro-m-cresol

Cas Number:

88-30-2

Molecular formula:

C7H4F3NO3

IUPAC Name:

α,α,α-trifluoro-4-nitro-m-cresol

impurity 1

Reference substance name:

5-chloro-α,α,α-trifluoro-2-nitrotoluene

EC Number:

204-280-7

EC Name:

5-chloro-α,α,α-trifluoro-2-nitrotoluene

Cas Number:

118-83-2

Molecular formula:

C7H3ClF3NO2

IUPAC Name:

4-Chloro-1-nitro-2-(trifluoromethyl)benzene

impurity 2

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Dihydrogen oxide

impurity 3

Reference substance name:

3-Carboxy-4-nitrophenol

Cas Number:

610-37-7

Molecular formula:

C7H5NO5

IUPAC Name:

3-Carboxy-4-nitrophenol

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source of test material:
Samples of TFM used for this study carried the following label information:
1-21-5479 C31 51315/1
JFK AIRPORT ATTN AMERICAN HOECHST CORP SOMMERVILLE N. J. MR. KUFAHL CHEM. DEPT.
MADE IN WEST GERMANY

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Sprague-Dawley, Madison, Wisconsin, USA
- Females nulliparous and non-pregnant: yes
- Age at study initiation: (P0) ~3 - 4 weeks
- Housing: individually, in metal screen bottom cages, 7" x 7" x 9 3/4"
- Diet: ad libitum, Purina Laboratory Chow from specially capped clear glass jars that limit spillage and contamination of feed and provide visibility of amount and condition of feed.
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23 ± 2
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: feed

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: The appropriate amount of TFM (85.6 %) was brought up to 1 % by weight of the diet with corn oil. The TFM and corn oil were thoroughly mixed, then totally admixed with the basal diet. The negative control diet consisted of the basal diet with a 1 % by weight addition of corn oil.

DIET PREPARATION
- Mixing appropriate amounts with: Purina Laboratory Chow (pellets)

VEHICLE
- Justification for use and choice of vehicle: In addition to facilitating good distribution of the test materials, the addition of the corn oil eliminated dusting, thus preventing personnel contamination and cross contamination of test animals from different diet groups.

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: one week
- Proof of pregnancy: vaginal plug referred to as day 1 of pregnancy.
- After seven days of unsuccessful pairing replacement of first male by another male with proven fertility.
- After successful mating each pregnant female was caged: Approximately five days prior to parturition, females were placed in plastic shoe box cages equipped with a stainless steel topf food jar, and water bottle. Bedding (AB-SORB-DRI) was changed three times weekly or more often if needed through weaning. After being placed in shoe boxes, females were allowed to deliver and care for their own young with a minimum of disturbance.

Duration of treatment / exposure:

After approximately 13 weeks on test diets, (18 weeks for the F0 generation), females were mated one to one with males from the same diet group.

Frequency of treatment:

continously

Details on study schedule:

The following description pertains to animals selected for reproduction studies from the F0, F1a, and F2b generations.
After approximately 13 weeks on test diets, (18 weeks for the Fo generation), females were mated one to one with males from the same diet group.
One week after weaning of the F2a or F3a litters, the parent generation was mated again in the described manner to produce a second litter.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

300 ppm

Remarks:

Group 8, conversion with generic animal data according to "Reproductively Active Chemicals" (factor for adult rats: 0.08)
300 ppm = 24 mg/kg bw/day

Doses / concentrations 2

Dose / conc.:

1 250 ppm

Remarks:

Group 9, conversion with generic animal data according to "Reproductively Active Chemicals" (factor for adult rats: 0.08)
1250 ppm = 100 mg/kg bw/day

Doses / concentrations 3

Dose / conc.:

5 000 ppm

Remarks:

Group 10, conversion with generic animal data according to "Reproductively Active Chemicals" (factor for adult rats: 0.08)
5000 ppm = 400 mg/kg bw/day

No. of animals per sex per dose:

40 (F0), 20 (F1, F2)

Control animals:

yes, concurrent vehicle

Examinations

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- If yes, maximum of 40 pups/litter (20/sex/litter as nearly as possible); excess pups were killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in [F1 / F2 / F3] offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain

GROSS EXAMINATION OF DEAD PUPS:
Yes

Reproductive indices:

mating index, fertility index, gestation index

Offspring viability indices:

viabilty index, survival index, lactation index

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P0)

In general, the data and calculated indexe appear normal for test and control groups. The fertility index, though normal, was slightly lower, for Group 9 (mid level TFM). Gestation index was excellent for all groups. Average numbers of pups born per litter were normal and no differences existed among the groups.

Effect levels (P0)

Key result

Dose descriptor:

NOAEL

Effect level:

400 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

reproductive performance

Target system / organ toxicity (P0)

Key result

Critical effects observed:

no

Results: P1 (second parental generation)

General toxicity (P1)

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Reproductive function / performance (P1)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P1)

A slightly lower fertility index (75 %) was seen in Group 9 (mid level TFM) when compared to the negative control group (90 %). Average numbers of pups born per litter were within normal limits. Viability index was good for all groups (89 - 96 %). Survival on day 4 is good for all groups and average pup weights were normal (8.6 g - 9.1 g). At day 21 (weaning), survival was good in all groups but average weaning weights were slightly smaller in Group 10 (45 g) when compared with weights in the negative control group, Group 7 (48 g).
Data from the second litter of the F1a generation (F2b litter) showed no changes in Fertility index and Mating index in the treament groups cmpared to the control group.
The number of newborn pups was not affected by the treatment.

Effect levels (P1)

Key result

Dose descriptor:

NOAEL

Effect level:

400 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

reproductive performance

Target system / organ toxicity (P1)

Key result

Critical effects observed:

no

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

mortality observed, non-treatment-related

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Group 10 (high level TFM) revealed reduced weaning weights in all litters (3 - 6 g) when compared to group 7 (negative control).

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Other effects:

not examined

Developmental neurotoxicity (F1)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F1)

Developmental immunotoxicity:

not examined

Details on results (F1)

A lower viability index was seen in Group 9 when compared to the other test and control groups. The primary cause for this lower viability index was that two litters accounted for a total of 21 dead pups, and not that all litters had a greater number of stillbirths. Survival, and lactation indexes were excellent for all groups. At 4 days average pup weights were normal, though smaller weights were seen in the high level TFM group (Group 10). At 21 days (weaning) depressed weights were seen in the high level TFM group (Group 10). Average weaning weight in Group 10 were 43 g and Group 12 46 g compared to 48 g - 49 g for other test and control groups. No other differences were seen among the groups regarding the reproduction data from F1a litters.

Effect levels (F1)

Key result

Dose descriptor:

NOAEL

Generation:

F1a

Effect level:

100 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Target system / organ toxicity (F1)

Key result

Critical effects observed:

no

Results: F2 generation

General toxicity (F2)

Clinical signs:

no effects observed

Mortality / viability:

mortality observed, non-treatment-related

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Group 10 (high level TFM) revealed reduced weaning weights in all litters (3 - 6 g) when compared to Group 7 (negative control).

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Other effects:

not examined

Developmental neurotoxicity (F2)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F2)

Developmental immunotoxicity:

not examined

Details on results (F2)

Viability was good for all groups (93 - 98 %). Only Group 9 showed day 4 pup weights below 10 g (9.1 g vs. 10.5 g in Group 7). At 21 days survival was good in all groups. Group 10 had average pup weights of 46 g and Group 8 had a weight of 48 g compared to 52 g seen in Group 7.

Effect levels (F2)

Key result

Dose descriptor:

NOAEL

Generation:

F2b

Effect level:

100 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Target system / organ toxicity (F2)

Key result

Critical effects observed:

no

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Any other information on results incl. tables

Additionally, the effects on a third generation were observed:

F3a: First litter data for the F2b generation revealed generally normal values for most groups. Group 10 showed a slightly lower number of pregnancies, Fertility index - 74 %, when compared to Group 7 (94 %). Mating indexes are essentially equal for all groups. Smaller average numbers of pups were born in Groups 10 and 12 (10.5 and 9.7) when compared to Group 7 (12.0). Viability was good (89 - 97 %) for all groups. Survival was good for all groups at day 4. Average pup weights at day 4 were normal for all groups. Survival was good in all groups at weaning (day 21). Weaning weights were slightly smaller in Group 10 than Group 7 (45 g vs. 48 g).

F3b: Fertility indexes were down or unchanged in all groups when compared with indexes of F3a litters. Mating indexes were, in general, up for all groups. Though within a normal range, smaller average numbers of pups were born in Groups 10 compared with Group 7. Groups 10 averaged 10.9 pups per litter compared with 13.0 pups in Group 7. Survival was good in all groups through weaning. Pup weights at day 4 were normal and revealed no differences among the groups. At 21 days a smaller average pup weight was seen in Group 10 (47 g) when compared with Group 7 (52 g).

Summary:

Overall reproductive performance in rats was generally good for most groups in all five litters (representing 3 generations) examined. Though some slight variations from litter to litter were seen, all average data and reproductive indexes were essentially normal and no significant reproductive differences were observed between the low level TFM or mid level TFM groups and the negative control group. A slightly lower Fertility index was observed in one or two groups from various litters. General overall fertility showed no abnormal variations between control and test groups, however. Gestation indexes were good throughout the study; essentially all positive pregnancies resulted in live births. Viability (Viability index) and survival through weaning (Survival index, Lactation index) were good for all groups through 3 generations. The average numbers of pups born per litter were, in most cases, within the normal range for this laboratory of approximately 9 - 12. Approximately half of the individual litters born in any given reproduction showed reduced number of pups born when compared to a normal range. Group 10 (high level TFM) revealed slightly reduced average numbers of pups born in both F3 litters when compared to the negative control. Average pup weights at day 4 showed slight variations among the groups, but all average weights were normal and no trend exists through 3 generations. At 21 days, weaning weights were normal and no consistent differences existed between the negative control group and the low and mid TFM groups. Group 10 (high level TFM) revealed reduced weaning weights in all litters (3 - 6 g) when compared to Group 7 (negative control).

Applicant's summary and conclusion

Conclusions:

In this 3-generation study similar to OECD guideline 416 in rats, no effect of the test substance on fertility was observed.

Executive summary:

In this study, the test substance was administered to 40 sex/dose (F0), or 20 sex/dose (F1, F2) Sprague-Dawley rats in diet at dose levels of 0, 300.0, 1250.0, and 5000.0 ppm (0, 24, 100, or 400 mg/kg bw/day). No changes in the reproductive indices of the treatment groups compared to the control group were observed in any generation. The only treatment-related effect observed was a reduction of weaning weights in the high dose group in the F1 and F2 generation.

Based on these observation, following NOAEL were determined:

P0: 5000 ppm (400 mg/kg bw/day) based on reproductive performance

P1:5000 ppm (400 mg/kg bw/day) based on reproductive performance

F1: 1250 ppm (100 mg/kg bw/day) based on body weight and weight gain

F2b:1250 ppm (100 mg/kg bw/day) based on body weight and weight gain

However, it can be assumed, that the observed weight difference between untreated control animals and treated animals (400 mg/kg bw/day) at weaning, is a transient effect. Comparing the weight gain of the femal P0, P1 and P2 animals of the corresponding treatment groups, no differences in bodyweight can be observed. Therefore, the observed weight difference at weanlings is not an adverse effect.