Sodium 3-[(1,5-dihydroxy-2-naphthyl)azo]-4-hydroxybenzenesulphonate

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Study period:

1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication/study report which meets basic scientific principles

Data source

Reference

Reference Type:

publication

Title:

STUDY OF THE TERATOGENIC POTENTIAL OF FD & C RED NO. 40 WHEN GIVEN BY GAVAGE TO RATS

Author:

COLLINS TFX, BLACK TN, WELSH JJ, BROWN LH

Year:

1989

Bibliographic source:

Fd Chem. Toxic. Vol. 27, No. 11, pp. 707-713. 1989

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 6-hydroxy-5-[(2-methoxy-4-sulphonato-m-tolyl)azo]naphthalene-2-sulphonate

EC Number:

247-368-0

EC Name:

Disodium 6-hydroxy-5-[(2-methoxy-4-sulphonato-m-tolyl)azo]naphthalene-2-sulphonate

Cas Number:

25956-17-6

Molecular formula:

C18H16N2O8S2.2Na

IUPAC Name:

disodium 6-hydroxy-5-[(2-methoxy-3-methyl-4-sulfonatophenyl)diazenyl]naphthalene-2-sulfonate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

FD & C Red No. 40,
Certified Batch No. AA-4181
Buffalo Color Corporation (Buffalo, NY, USA)

Test animals

Species:

rat

Strain:

Osborne-Mendel

Details on test animals or test system and environmental conditions:

Male and female Osborne Mendel (FDA strain) rats were obtained from the FDA rat breeding colony.
At the start of the study, female rats were 12-21 wk old and weighed 220-270 g.
Rats have been used traditionally in teratology studies, and the Osborne-Mendel FDA strain was chosen because of the availability of historical data.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

distilled

Details on exposure:

FD & C Red No. 40 was dissolved in distilled water (w/v) at concentrations of 3, 7.5, 15, 30, 60 and 100 mg/mL
Fresh solutions were prepared daily and administered by gavage in a volume of 1 ml/100 g body weight, at approximately the same
time each day.
Controls received an equivalent volume of distilled water.

Details on mating procedure:

Two females were randomly mated with one male
The following morning, a vaginal smear was obtained from each female to determine whether copulation had taken place.
Sperm-positive dams were considered to be at day 0 of gestation.

Duration of treatment / exposure:

Each animal was treated daily from day 0 to day 19 of gestation

Frequency of treatment:

daily

Duration of test:

until day 20 of gestation

No. of animals per sex per dose:

42-43 presumably pregnant females were assigned to each dose group by random number

Control animals:

yes, concurrent vehicle

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: no data

DETAILED CLINICAL OBSERVATIONS: No data
- Time schedule:

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION: Yes
- Time schedule for examinations: weekly

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data
- Time schedule for examinations:

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day #20
- Organs examined: gross abnormalities; Corpora lutea were counted. The uterus was opened and examined in situ. The uterine
positions of all implantation sites were noted and their condition (early or late resorptions, living or dead foetuses) was determined.

OTHER:

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No data
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Other:

Fetal examinations:

Each live foetus was promptly weighed, sexed and examined for gross external malformations, and the crown-rump length was measured. Any foetus that weighed less than 70% of the average weight of the concurrent male or female controls was considered to be a runt (Leuschner and Czok, 1973). Approximately one-half of the foetuses were fixed in alcohol, stained with Alizarin Red S and examined under a dissecting microscope for all skeletal variations. The remaining half of the foetuses were fixed in Bouin's solution, serially sectioned by razor blade and examined under a dissecting microscope for internal variations of the soft tissues.

Statistics:

All data analyses were performed by the Division of Mathematics at the FDA. Data on maternal initial body weights and food consumption were analysed by straight analysis of variance (ANOVA) and two-tailed t-test, and a regression analysis. The number of dams affected was analysed by a Fisher's exact test. Data on maternal weight gain were submitted to an analysis of covariance (ANOCOVA) and a two-tailed t-test. Data on
the numbers of implants, corpora lutea, total viable young and viable males and females were analysed by ANOVA followed by a one-tailed t-test. Data on implantation efficiency, early deaths, late deaths and total resorptions (early and late deaths) were transformed by using the Freeman-Tukey arc-sine transformation (Freeman and Tukey, 1950) and then analysed by ANOVA and a one-tailed t-test. Data on litters having one or more or two or more resorptions were analysed by a Fisher's exact test. Similar tests were applied to the number of runts per litter. Data on foetal body weights, crown-!o-rump lengths and foetal ossified vertebrae were analysed by nested ANOVA and a one-tailed t-test. The ANOVA included a correction for unequal sample size (Sokal and Rohlf, 1981). Data on the average number of foetuses per litter with skeletal, sternebral, combined
missing plus incomplete plus bipartite sternebrae or soft-tissue variations were transformed by using the Freeman-Tukey arc-sine transformation and then analysed by ANOVA and a one-tailed t-test. Litters with foetuses with at least one, at least two, etc.. skeletal, sternebral, combined missing plus incomplete plus bipartite sternebrae, or soft-tissue variations, and specific variations were analysed by Fisher's exact test.

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
No unusual behaviours were observed in the animals during the study. The external maternal findings were unremarkable. One female in the group given 300 mg/kg died at day 12 of gestation as a result of garage difficulties unrelated to dosage. The gavage difficulties, which occurred on day 3, caused the animal to consume only 4-5g food per day and consequently to lose weight during the last week of life.
Mean food consumption on days 0-7, 7-14, 14 20 and 0-20 by the treated animals was similar to that of the control animals. Initial body weight at day 0 and maternal body-weight gain during gestation were similar in all groups.

Effect levels (maternal animals)

1

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

2

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
Mean foetal weights of males and females and crown rump lengths were similar in all groups.
No test substance-related skelettal or soft-tissue defects were noted.

Effect levels (fetuses)

1

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: teratogenicity

2

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: embryotoxicity

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

No dose-related maternal or developmental effects occurred when FD & C Red No. 40 was given by gavage at dose levels of up to 1 g/kg/day.The NOAEL for maternal developmental and teratogenic effects was 1000 mg/kg bw

Executive summary:

Osborne-Mendel rats were intubated with FD & C Red No. 40 at dose levels of 0, 30, 75, 150, 300, 600 or 1000 mg/kg body weight/day on days 0-19 of gestation. No developmental toxicity was observed when the animals were killed on day 20 of gestation. No dose-related changes were seen in maternal daily observations, food consumption, body-weight gain or implantations, or in foetal viability, body weight, body length, sex distribution or external variations. Skeletal and soft-tissue development appeared similar in foetuses of all groups. The isolated increases that occurred in the number of male foetuses, number of females with two or more resorptions, number of litters with three or more sternebral variations and incidence of 14th rib bud are considered random occurrences and were not related to dosage.