Aluminium tribenzoate

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1972

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1972

Report date:

1972

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

See "Principles of method if other than guideline"

Principles of method if other than guideline:

Exposure started gestation day 6 (recommended start on day 5), dose level choice not justified (highest dose tested did not induce maternal effects), number of corpora lutea not determined, limited information on test substance included in report. No information on feed and environmental conditions, no analytical verification of doses, only average fetus weight males and females together per litter, no individual information on the pups, no historical control data, limited maternal toxicity parameters.

GLP compliance:

no

Remarks:

Study performed before GLP principles were implemented

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Sodium benzoate

EC Number:

208-534-8

EC Name:

Sodium benzoate

Cas Number:

532-32-1

Molecular formula:

C7H6O2.Na

IUPAC Name:

Sodium benzoate

Test material form:

solid: particulate/powder

Remarks:

Fine white powdered material

Details on test material:

Name in the report: FDA 71-37

Test animals

Species:

hamster

Strain:

other: Golden hamster

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: Individually housed in mesh bottom cages
- Diet: ad libitum
- Water: fresh tap water, ad libitum

ENVIRONMENTAL CONDITIONS
- The cages were kept in temperature and humidity-controlled quarters

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

Animals were dosed at 1.0 mL/kg bw.

Analytical verification of doses or concentrations:

no

Details on mating procedure:

Virgin adult female hamsters were mated with young adult males (1:1), and appearance of motile sperm was considered day 0 of gestation.

Duration of treatment / exposure:

Gestation day 6 to 10

Frequency of treatment:

Daily

Duration of test:

Hamsters were sacrificed on gestation day 14.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

3 mg/kg bw/day (actual dose received)

Doses / concentrations 2

Dose / conc.:

14 mg/kg bw/day (actual dose received)

Doses / concentrations 3

Dose / conc.:

65 mg/kg bw/day (actual dose received)

Doses / concentrations 4

Dose / conc.:

300 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

Pregnant females: 22 (negative control), 21 (positive control), 22 (group exposed to 3.0, 14.0 and 65.0 mg/kg bw/day), 21 (group exposed to 300.0 mg/kg bw/day).

Control animals:

yes

yes, sham-exposed

Examinations

Maternal examinations:

Body weights were recorded on days 0, 8, 10, and 14 of gestation. All animals were observed daily for appearance and behaviour with particular attention to food consumption and weight, in order to rule out any abnormalities which may have occurred as a result of anorexic effects in the pregnant females.

Ovaries and uterine content:

On day 14 all dams were subjected to Caesarean section under surgical anesthesia, and the numbers of corpora lutea, implantation sites, resorption sites, and live and dead fetuses were recorded. The urogenital tract of each dam was examined in detail for anatomical normality.

Fetal examinations:

The number of live and dead fetuses was recorded. The body weights of the live pups were recorded. The sex of all pups was determined.
All fetuses were examined grossly for the presence of external congenital abnormalities. One-third of the fetuses of each litter underwent detailed visceral examinations employing 10X magnification. The remaining two-thirds were cleared in potassium hydroxide (KOH), stained with alizarin red S dye and examined for skeletal defects.

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:

not specified

Mortality:

mortality observed, non-treatment-related

Description (incidence):

No mortality occurred in the control group and in the groups exposed to 14.0, 65.0 and 300.0 mg/kg bw/day. One female died in the group exposed to 3.0 mg/kg bw/day (killed on day 13 after abortion).

Body weight and weight changes:

no effects observed

Description (incidence and severity):

The body weight increase of pregnant dams was comparable between the groups exposed to sodium benzoate and the control group.

Maternal developmental toxicity

Number of abortions:

no effects observed

Description (incidence and severity):

One female exposed to 3.0 mg/kg bw/day aborted on day 13. This was considered to be incidental and not related to the test item exposure. No other abortions were observed in the groups exposed to the test item or in the control group.

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

The average number of corpora lutea per dam was 15.7, 15.2, 14.7, 14.9 and 15.1 for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively. The average number of implantation sites per dam was 13.2, 11.6, 11.9, 12.2 and 12.3 for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively. The average number of live fetuses per dam were 12.9, 11.1, 11.3, 11.8 and 11.9 for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively. The exposure to the test substance did not have an effect on implantation loss.

Total litter losses by resorption:

no effects observed

Description (incidence and severity):

All pregnant dams had live litters.

Early or late resorptions:

effects observed, non-treatment-related

Description (incidence and severity):

The total number of resorptions was 6, 8, 12, 8 and 9 for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively. The percentage of dams with partial resorptions was 27.3%, 23.8%, 40.9%, 31.8% and 28.6% for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively.

Dead fetuses:

effects observed, non-treatment-related

Description (incidence and severity):

The total number of dead fetuses was 2, 2, 2, 2 and 1 for the negative control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively.

Changes in number of pregnant:

effects observed, non-treatment-related

Description (incidence and severity):

One female exposed to 3.0 mg/kg bw/day aborted on day 13. This was considered to be incidental and not related to the test item exposure. No other abortions were observed in the groups exposed to the test item or in the control group.

Effect levels (maternal animals)

Key result

Dose descriptor:

NOAEL

Effect level:

>= 300 mg/kg bw/day (actual dose received)

Based on:

test mat.

Remarks on result:

other: No adverse effects observed up to and including the highest dose tested.

Maternal abnormalities

Key result

Abnormalities:

no effects observed

Results (fetuses)

Fetal body weight changes:

no effects observed

Description (incidence and severity):

The average fetus weight was 1.81, 1.84, 1.80, 1.84 and 1.86 g for the control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively.

Changes in sex ratio:

no effects observed

Description (incidence and severity):

The sex ratio (M/F) for the live fetuses was 0.45, 0.52, 0.45, 0.62 and 0.43 for the control group and the groups exposed to 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day, respectively. All values for the exposed groups were comparable to the sex ratio in the control group.

External malformations:

no effects observed

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

The number of skeletal malformations in the exposed groups did not differ from the control group (results summarized below) and/or did not show a dose-related increase and were therefore considered not to be related to the test item.

Visceral malformations:

no effects observed

Description (incidence and severity):

No soft tissue abnormalities were observed in any of the groups.

Effect levels (fetuses)

Key result

Dose descriptor:

NOAEL

Effect level:

>= 300 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects seen up to and including the highest dose tested

Fetal abnormalities

Key result

Abnormalities:

no effects observed

Overall developmental toxicity

Key result

Developmental effects observed:

no

Any other information on results incl. tables

	Control	3.0 mg/kg bw/day	14.0 mg/kg bw/day	65.0 mg/kg bw/day	300.0 mg/kg bw/day
Live fetuses examined (pregnant dams)	195/22	163/21	171/22	178/22	171/21
Sternebrae
incomplete ossification	101/22	85/20	98/21	102/21	92/21
Bipartite	18/14	20/13	22/16	23/16	14/10
Extra	-	-	6/1	-	1/1
Missing	18/11	7/5	32/13	17/8	14/8
Ribs
More than 13	20/15	35/17	34/16	23/11	29/20
Vertebrae
Incomplete ossification	-	-	3/3	-	-
Extremities
Incomplete closure	-	-	2/2	1/1	-
Miscellaneous
Hyoid, missing	-	-	5/2	-	-
Hyoid, reduced	-	-	-	-	1/1

 

Numerator = number of foetuses affected; Denominator = Number of litters effected

Applicant's summary and conclusion

Conclusions:

Hamsters were exposed to sodium benzoate at 0, 3.0, 14.0, 65.0 and 300.0 mg/kg bw/day via oral gavage for 10 consecutive days during pregnancy (gestation days 6 to 15). At sacrifice on day 14, No effects were seen in maternal animals or fetuses. The nature and number of skeletal abnormalities in the test groups did not differ from the controls. No soft tissues abnormalities were observed. Based on these results, it is concluded that the NOAEL (maternal and development) is at least 300 mg/kg bw/day in hamsters.