Malonic acid

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

In a combined repeated dose toxicity study with the reproduction/developmental toxicity screening test [OECD TG 422], Crj: CD (SD) IGS rats were given disodium succinate hexahydrate by gavage at 0, 100, 300, or 1,000 mg/kg bw/day. Males were dosed for 52 days from day 14 before mating and females were dosed from day 14 before mating to day 4 of lactation throughout the mating and pregnancy period. The study showed that the reproduction/developmental parameters, i.e., mating, pregnancy, delivery, lactation, and viability and body weight of pups, were not affected by disodium succinate hexahydrate at up to 1,000 mg/kg bw/day. The NOAEL of disodium succinate hexahydrate for reproduction/developmental toxicity was considered to be 1,000 mg (highest dose tested, equivalent to 600 mg of disodium succinate)/kg bw/day in rats.

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2002

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

Succinic acid may be used as an analogue for malonic acid, based on the following considerations. Firstly, dicarboxylic acids are naturally occurring metabolic products of fatty acid oxidation, and are rapidly beta-oxidised. A category approach for short-medium chain dicarboxylic acids, including malonic acid and succinic acid, has been validated and used by various bodies including the Cosmetics Ingredient Review Panel and the European Food Safety Authority.Disodium succinate may be used as an analogue for succinic acid as there is no significant difference in toxicity expected between succinic acid and disodium succinate, since both substances will dissociate into succinate ion under physiological conditions.

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

Test substance: disodium succinate hexahydrate (CAS No. 6106-21-4),Nippon Shokubai Co., Ltd., Purity 99.9%, Lot No. 9P01B

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Route of administration:

oral: gavage

Vehicle:

not specified

Duration of treatment / exposure:

Males; for 52 daysFemales; from 14 days before mating to day 4 of lactation

Frequency of treatment:

Once daily

Dose / conc.:

0 mg/kg bw/day

Dose / conc.:

100 mg/kg bw/day

Dose / conc.:

300 mg/kg bw/day

Dose / conc.:

1 000 mg/kg bw/day

No. of animals per sex per dose:

No. of animals/group: males 12, females 12

Control animals:

yes, concurrent vehicle

Parental animals: Observations and examinations:

Clinical observations

Litter observations:

Yes

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Reproductive function: oestrous cycle:

no effects observed

Copulation and fertility:Copulation and conception were all established, and both the copulation index and the fertility index were 100% in all groups. In the observation of estrous cycle, there was no intergroup difference in the mean estrous cycle. The abnormal estrous cycle was observed in 1 animal each in the 100 and 1000 mg/kg groups. There was no intergroup difference in the incidence of abnormal estrous cycle.Parturition and lactation:The gestation period was significantly shortened in the 100 and 1000 mg/kg groups compared with the control group. There was no abnormality in the conditions of parturition, and the numbers of corpora lutea, implantation sites, delivered offspring and live delivered offspring showed almost the same values. There were no intergroup differences in the delivery index, implantation index, parturition index, live birth index, sex ratio and viability index of neonates on day 4 of lactation.

Dose descriptor:

NOAEL

Effect level:

> 1 000 mg/kg bw/day (nominal)

Remarks on result:

not determinable due to absence of adverse toxic effects

Critical effects observed:

no

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

In the external examination in neonates, anophthalmia and polydactyly were observed in 1 animal each in the 300 mg/kg group.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Body weight during lactation period was significantly low on days 0 and 4 of lactation in males and day 4 in females in the 100 mg/kg group and on day 4 in males in the 300 mg/kg group, which was the change not associated with the dose.

In the necropsy on day 4 of lactation, red patches on the plantar were observed in 15 males and 13 females in the 100 mg/kg group, and the number of occurrences significantly increased in both males and females compared with the control group. However, this finding occurred in litters in 2 broods in both males and females. In addition, dilation of the ureter was observed in 3, 4 and 3 males and 5, 1 and 2 females in the 100, 300 and 1000 mg/kg groups, respectively, and the number of occurrences significantly increased in the male 100 mg/kg group. However, dilation of the ureter in the female 100 mg/kg group was observed in litters in 4 of 5 animals. Other findings included thymic remnant in the neck in 3, 1, 2 and 3 male animals in the control, 100, 300 and 1000 mg/kg groups and in 1, 2 and 2 female animals in the control, 100 and 300 mg/kg groups, nodes in the liver in 1 animal each in the male and female 1000 mg/kg groups, white patches in the liver in 1 animal in the male 100 mg/kg group, pyelectasia in 3 animals each in the male 100, 300 and 1000 mg/kg groups and in 2 and 1 animal in the female 300 and 1000 mg/kg groups, anophthalmia in 1 animal in the female 300 mg/kg group, cysts in the hindlimbs in 1 animal in the female 100 mg/kg group and polydactyly in 1 animal in the female 300 mg/kg group.

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

not specified

Remarks on result:

not determinable due to absence of adverse toxic effects

Critical effects observed:

no

Reproductive effects observed:

no

Conclusions:

There is no evidence that disodium succinate has reproductive/developmental toxicity in rats. The NOAEL for reproduction/developmental toxicity wasconsidered to be 1000 mg/kg bw/day as disodium succinate hexahydrate (600 mg/kg bw/day as disodium succinate.

Executive summary:

In a combined repeated dose toxicity study with the reproduction/developmental toxicity screening test [OECD TG 422], Crj: CD (SD) IGS rats were given disodium succinate hexahydrate by gavage at 0, 100, 300, or 1,000 mg/kg bw/day. Males were dosed for 52 days from day 14 before mating and females were dosed from day 14 before mating to day 4 of lactation throughout the mating and pregnancy period. The study showed that the reproduction/developmental parameters, i.e., mating, pregnancy, delivery, lactation, and viability and body weight of pups, were not affected by disodium succinate hexahydrate at up to 1,000 mg/kg bw/day. The NOAEL of disodium succinate hexahydrate for reproduction/developmental toxicity was considered to be 1,000 mg (highest dose tested, equivalent to 600 mg of disodium succinate)/kg bw/day in rats.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

600 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Effects on developmental toxicity

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

600 mg/kg bw/day

Study duration:

subchronic

Species:

rat