Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 205-739-4
CAS number: 149-44-0
The purpose of this study was to investigate the effects of Sodium
Hydroxymethansulfinate on pregnancy and embryo-foetal development in the
Wistar rat, following oral administration, at dose levels of 100, 300
and 1000 mg/kg/day.
Females were dosed starting from Day 6 until Day 19 post coitum. The
test item was administered, by the oral route, at a dose volume of 10
mL/kg. The vehicle was purified water. The following investigations were
performed: mortality check, clinical signs, body weight, food
consumption and macroscopic observation of the females. On Day 20 post
coitum at necropsy, gravid uterus weight, corpora lutea, implantation
sites, number, sex and weight of all foetuses were determined. Gross
evaluation of the placenta and external examination on all foetuses were
also performed. Fixed-visceral and skeletal examinations were performed
on foetuses of all groups.
Fate of females
No deaths related to treatment occurred. The number of females with live
foetuses on gestation Day 20 was 21 in the control group, 22 in the low
dose group, 20 in the mid-dose group and 23 in the high dose group. One
female in the mid-dose group was sacrificed on Day 13 post coitum with
litter since pups were found on the cage tray.
No signs related to treatment, nor signs of reaction to treatment were
observed during the dosing period.
Body weight and body weight gain
A slight statistically significant decrease in body weight was observed
from Day 15 to Day 20 of gestation in high dose females (receiving 1000
No toxicological relevant changes were seen in body weight in low and
mid-dose females (100 and 300 mg/kg/day).
No toxicological significance was attributed to the slight increase
(statisticallysignificant) in body weight gain observed in females
receiving 100 mg/kg/day on Day 12 of gestation and in females receiving
300 mg/kg/day on Day 6 of gestation (before treatment start).
In addition, a statistically significant decrease in body weight gain
was observed on Days 9, 15 and 20 of gestation in the high dose group
A decrease in food consumption with statistical significance on Days 9
and 12 of post coitum was recorded in high dose females (receiving 1000
mg/kg/day), starting from Day 9 of post coitum to the end of treatment.
No relevant effects on food consumption were seen in low and mid-dose
females (100 and 300 mg/kg/day).
Terminal body weight, uterus weight and absolute weight gain
Terminal body weight of high dose females was reduced compared to
controls and a statistically significant decrease in absolute weight
gain (terminal body weight at necropsy minus gravid uterine weight,
minus body weight at Day 0 post coitum) was also noted.
Litter data and sex ratios
Litter data, mean foetal weight and sex ratios were not affected by
No treatment-related changes were observed at post mortem examination in
treated animals, when compared to the controls.
External examination of foetuses
Small foetuses were present in all groups including controls with
Skeletal examination of foetuses
At skeletal examination the following malformations in foetuses from
different litters were observed:
- pubis unossified was seen in 2 foetuses in the low dose group (100
mg/kg/day) corresponding to 1.53% of foetuses and 4.55% of litters, in 5
foetuses in the mid-dose group (300 mg/kg/day) corresponding to 4.24% of
foetuses and 10.00% of litters and in 2 foetuses in the high dose group
(1000 mg/kg/day) corresponding to 1.41% of foetuses and 8.70% of litters;
-ischium unossified was seen in 1 foetus in the mid-dose group (300
mg/kg/day) corresponding to 0.85% of foetuses and 5.00% of litters and
in 1 foetus in the high dose group (1000 mg/kg/day) corresponding to
0.70% of foetuses and 4.35% of litters.
Pubis and ischium unossified are not present in the historical control
An increased presence of additional rudimentary 14th rib (variant) was
noted in all groups with particular emphasis in the low dose and high
dose groups (100 and 1000 mg/kg/day), incomplete ossification of
sternebrae (variant) was noted in the mid- and high dose groups (300 and
1000 mg/kg/day), metatarsals of the hind paw incompletely or unossified
(anomaly) were observed in all treated group with particular emphasis in
the mid-dose group (300 mg/kg/day).
Visceral examination of foetuses
At visceral examination the following malformations in foetuses from
different litters were observed:
- anophtalmia was seen in 2 foetuses in the mid-dose group (300
mg/kg/day) corresponding to 1.80% of foetuses and 10.00% of litters and
1 foetus in the high dose (1000 mg/kg/day) corresponding to 0.78% of
foetuses and 4.35% of litters.
- hydrourether was seen in 2 foetuses in the high dose group (1000
mg/kg/day) corresponding to 1.56% of foetuses and 8.70% of litters.
-umbilical hernia was seen in 1 foetus in the high dose (1000 mg/kg/day)
corresponding to 0.78% of foetuses and 4.35% of litters.
No malformations were noted in foetuses of the low dose group (100
As a consequence of the findings, a classification of the substance into
the hazard class “Reproductive toxicity”, Category 2 (H361d)
according to the Regulation (EC) No. 1272/2008 is recommended.
Based on the experimental results, the criteria for classification into
Category 1 are not met. However, the above mentioned adverse effects on
pup development should be considered. Taking into account of the actual
substance’s classification into the hazard class “Germ cell
mutagenicity” category 2, which is based on test data of the substance,
a classification of the substance as “reproductive toxic, Category 2;
H361d” appears to be appropriate.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again