Potassium mercaptoacetate

Endpoint summary

Description of key information

KTG is toxic by ingestion (Acute Tox 3).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

05-June-2000 - 19-July-2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Male and female Sprague Dawley rats CD (Crl: CD (SD) IGS BR)
- Supplier: Charles River (UK) Ltd, Margate, Kent, UK
- Weight: 221-229 g (M), 202-232 g (F)
- Age: 12 weeks
- Acclimatization:  at least 5 days
- Housing: groups of 3 by sex in solid-floor polypropylene cages
- Diet: ad libitum except fasting (Rat and Mouse Expanded Diet N°1, Special  Diets Services Limited, Witham, Essex, UK)
- Water: drinking water ad libitum
- Fasting: overnight before dosing and 3-4 hours after dosing

CONDITIONS:
- Temperature: 19-25 °C
- Relative Humidity: 30-70 %
- Air changes: approx. 15/hour
- Dark-Light cycle (hours): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Doses:

200, 500 and 2000 mg/kg potassium thioglycolate as 42.5% solution.

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

All animals were dosed once only by gavage. The animals were observed for  death or overt signs of toxicity 1/2, 1, 2 and 4 hours after dosing and  subsequently twice daily for up to 14 days. Individual body weights were  recorded prior to dosing and 7 and 14 days after treatment or at death. At the end of the observation period, animals were subjected to  macroscopic examination. No tissue was retained.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

>= 200 - <= 500 mg/kg bw

Based on:

test mat.

Mortality:

All animals treated with 2000 mg/kg, one animal treated with 500  mg/kg and one animal treated with 200  mg/kg were found dead during the day of dosing. The two remaining animals treated with 500 mg/kg were found dead one day after dosing.

Clinical signs:

other: Hunched posture was commonly noted at dose levels of 2000 mg/kg, 500 mg/kg and in females treated with 200 mg/kg with lethargy also commonly noted at 2000 mg/kg and ataxia also commonly noted at 500 mg/kg. lncidents of decreased respiratory rate and labou

Gross pathology:

Abnormalities noted at necropsy of animals that died during the study  were haemorrhagic lungs, dark liver, dark kidneys, epithelial sloughing of thegastric mucosa and haemorrhage of the bladder. No abnormalities were noted at necropsy of animals that were killed at the end of the study.

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

The acute oral median lethal dose LD50 of potassium thioglycolate 43% solution was estimated to be in the range of 200-500 mg/kg.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

200 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because exposure of humans via inhalation is not likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07-Mar-2012 - 28-Aug-2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

French Republic, Prime Minister, Interministerial Group on Chemicals (GIPC)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Breeder: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: approximately 9 weeks
- Weight at study initiation: 290 ± 7 g for the males and 228 ± 6 g for the females
- Water and food: ad libitum
- Acclimation period: at least 5 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 30 to 70
- Ventilation: approximately 12 cycles/hour of filtered, non-recycled air.

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: a dorsal area of the skin (approximately 5 cm x 6 cm for the females and 5 cm x 7 cm for the males)
- % coverage: approximately 10%
- Type of wrap if used: hydrophilic gauze pad held in contact with the skin by means of an adhesive hypoallergenic aerated semi-occlusive dressing and a restraining bandage
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 1.64 mL/kg
- Constant volume or concentration used: no

Duration of exposure:

24 h

Doses:

A single dose of 2000 mg/kg of the test item in its original form was placed on a hydrophilic gauze pad and then applied to the clipped area of the skin.

No. of animals per sex per dose:

5

Control animals:

yes, concurrent no treatment

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One female, which was accidentally wounded on the removal of the dressing, was killed on day 2 for ethical reasons. No deaths related to treatment occurred during the study.

Clinical signs:

other: No clinical signs were observed during the study.

Gross pathology:

Macroscopic examination of the main organs of the animals revealed no apparent abnormalities.

Interpretation of results:

GHS criteria not met

Conclusions:

Under the experimental conditions, the dermal LD50 of KTG is higher than 2000 mg/kg in rats.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

LD50 determined with KTG is >2000 mg/kg bw for rats.

Additional information

Thioglycolic acid and its salts are toxic by oral administration. When expressed as thioglycolate anion, the LD₅₀values of thioglycolic acid and its salts are more or less in the same dose range LD₅₀ ≥ 50 mg/kg a. i. thioglycolate.

Justification for selection of acute toxicity – oral endpoint
LD50 determined with KTG (ATC method).

Justification for classification or non-classification

Based on acute oral toxicity data in rats.

Classification:

EU-GHS: Acute tox cat. 3. H301. Toxic if swallowed.