Mercaptoacetic acid

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Original reference in Russian Documentation insufficient for assessment

Data source

Reference

Reference Type:

publication

Title:

Toxicology of thioglycolic acid

Author:

Rotenberg YS, Klochkova SI, Mashbits FD and Eisenhart RS

Year:

1969

Bibliographic source:

Gig Truda prof Zabol, 13, 48-50 (in Russian)

Materials and methods

Test guideline

Qualifier:

no guideline followed

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Mercaptoacetic acid

EC Number:

200-677-4

EC Name:

Mercaptoacetic acid

Cas Number:

68-11-1

Molecular formula:

C2H4O2S

IUPAC Name:

2-sulfanylacetic acid

Details on test material:

no data

Test animals

Species:

rat

Strain:

not specified

Sex:

male

Administration / exposure

Route of administration:

inhalation

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

5 months

Frequency of treatment:

not clearly specified

Doses / concentrations

Remarks:

Doses / Concentrations:
0.45 and 1.25 mg/m3
Basis:

No. of animals per sex per dose:

50

Control animals:

yes, concurrent no treatment

Details on study design:

Post-exposure period: none

Results and discussion

Results of examinations

Details on results:

Changes in liver function (increased  bromsulphophtalein excretion and synthesis of hippuric acid) occurred in  the top dose group from the middle of the third month (p < 0.05). Similar  effects in the low dose group did not achieve statistical significance  when compared to 50 untreated controls. From the fifth month in the top  group, the levels of free histamine in the skin and brain were increased;  there was a decrease in "the histaminopectic effect" of both tissues.  Although there was some evidence of these effects in the low dose group,  statistical significance was not demonstrated. Blood samples from the  upper dose group showed reduced adrenocorticotropic activity (adrenal  effects) during the first month, which were increased in the fourth month  of treatment. No similar effects were seen in the low dose group. Animals  from both dose groups showed effects on the neurosecretory activity of  neurons (supraoptical and periventricular) of the anterior hypothalamus.  No effects were noted on blood sugar levels in either treated groups.  Gross examinations of organs from the top dose group showed some atrophy  of the mucosa of the upper respiratory tract, bronchi and "parenchymatous  organs" (presumably the liver). Substantial other effects were seen in  the liver including fatty degeneration of parenchyma cells. The low dose  group apparently exhibited some effects on the liver parenchyma cells  which were described as typical of a "reactive state", and mild catarrh  in the upper respiratory tract. The low dose level was considered to lie  near to the threshold for effects under the conditions of this study.

Effect levels

Dose descriptor:

LOAEL

Effect level:

0.45 mg/m³ air

Sex:

male

Target system / organ toxicity

Critical effects observed:

not specified