Ammonium mercaptoacetate

Endpoint summary

Description of key information

Ammonium thioglycolate is toxic if swallowed (Acute Tox 3). ATG is non-toxic by the percutaneous route. 

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

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)

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Animals:
Source: Fa. Harlan Winkelmann GmbH, 33178 Borchen
Acclimatization period: 15-21 days
Weight range at study initiation: 260-282 g (m), 189-206 g (f)
Fasting: 16 hours before dosing and 3-4 hours after dosing

Husbandry:
Housing: collective housing up to a maximum of 3 animals per cage (Makrolon type III)Illumination: artificial lighting from 7.00 a.m.-7.00 p.m.
Temperature: 22±3 °C
Relative humidity: 30-70%

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The acute oral toxicity of "Ammonium thioglycolate 71 %" was investigated according to a stepwise procedure in Wistar rats.
Three animals of one sex are used for each step.

On the basis of toxicity data from the test substance, a starting group of 3 female rats received a single oral administration of "Ammonium thioglycolate 71 %" in a dose of 200 mg/kg body weight. Based on the stepwise procedure, further groups using 3 females and 3 males each were treated with doses of 25 and 50 mg/kg body weight, respectively.

Doses:

25, 50, 200 mg/kg of the 71% ammonium thioglycolate solution

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

Clinical observations were conducted at regular intervals during the 14-day observation period.
Gross pathological examinations were performed immediately on animals found dead and at termination on day 14 on surviving animals.
Body weights were measured at days 0, 7 and 14.

Statistics:

not appropriate

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 50 - < 200 mg/kg bw

Based on:

test mat.

Remarks:

71% solution

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 35 - < 142 mg/kg bw

Based on:

act. ingr.

Mortality:

All 3 female rats treated with 200 mg/kg body weight died pre-terminally. All animals of the other dose groups survived the whole observation period of 14 days.

Clinical signs:

other: All 3 rats treated with 200 mg/kg body weight showed severe clinical symptoms appearing 2 h post-administration and leading to death. All 3 female rats which received 50 mg/kg body weight exhibited alopecia on day 14 post administration. No other clinical

Gross pathology:

Gross pathological examinations on day 14 post administration (terminal necropsy) revealed no test article-dependent findings in the lower dose groups of 25 and 50 mg/kg body weight. In all 3 female rats which received 200 mg/kg body weight and died spontaneously, test article-dependent findings were observed.

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

The median acute lethal dose for rats of both sexes is 50 to 200 mg/kg bw for the 71% solution of Ammonium Thioglycolate. According to Table 3.1.2 of the CLP regulation, this range can be converted to a point estimate of 100 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

100 mg/kg bw

Quality of whole database:

The median acute lethal dose for rats of both sexes is 50 to 200 mg/kg bw for the 71% solution of Ammonium Thioglycolate. According to Table 3.1.2 of the CLP regulation, this range can be converted to a point estimate of 100 mg/kg bw.

Acute toxicity: via inhalation route

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

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:

fixed dose procedure

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: approximately 9 weeks
- Weight at study initiation: 309 ± 9 g for the males and 227 ± 4 g for the females
- Housing: single
- Diet (e.g. ad libitum): A04 C pelleted diet (SAFE, Villemoisson, Epinay-sur-Orge,France), ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 30 to 70
- Air changes (per hr): approximately 12
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 11 March 2003 To: 25 March 2003

Type of coverage:

semiocclusive

Vehicle:

water

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:

2000 mg/kg of a 71,5% aqueous solution (equivalent to 1430 mg/kg of the active ingredient)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:The animals were observed frequently during the hours following administration of the test itemfor detection of possible treatment-related clinical signs. Thereafter, observation of the animals was made at least once a day until day 15.
From day 2, any local cutaneous reaction was recorded.
The animals were weighed individually just before administration of the test item on day 1 and then on days 8 and 15.
The body weight gain of the treated animals was compared to that of CIT control animals with a similar initial body weight.
- Necropsy of survivors performed: yes
- Other examinations performed: Macroscopic necropsy examination:All study animals were subjected to a macroscopic examination as soon as possible after death. After opening the thoracic and abdominal cavities, a macroscopic examination of the main morgans (digestive tract, heart, kidneys, liver, lungs, pancreas, spleen and any other organs with obvious abnormalities) was performed. Preservation of tissues: No organ samples were taken.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 1 430 mg/kg bw

Based on:

act. ingr.

Mortality:

No deaths were observed during the study.

Clinical signs:

other: No clinical signs were observed during the study.

Gross pathology:

No apparent abnormalities were observed at necropsy in any animals.

Other findings:

No cutaneous reactions were observed.

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 is higher than 2000 mg/kg of a 71.5% aqueous solution (equivalent to 1430 mg/kg of the active ingredient)

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

The acute oral toxicity of ammonium thioglycolate was tested in male and female rats according to the Acute Toxic Class Method (OECD guideline 423). The LD50 of the 71% aqueous solution of ammonium salt was between 50 and 200 mg/kg bw in Sprague-Dawley rats (Hönack, 1996).

Another study performed with ammonium thioglycolate according to the OECD guideline 401 leads to an acute LD50 between 25 and 200 mg a.i./kg bw in Wistar rats (Heusener, 1988).

In studies performed in Sprague-Dawley rats according to the OECD guideline 402, no mortality was observed after dermal application of 2000 mg/kg bw of 71% aqueous solution ammonium thioglycolate and clinical signs were limited to moderate skin irritation at the site of application. The LD50 was therefore above 2000 mg/kg bw (Klein, 2003a).

In a former study with 71% aqueous solution ammonium thioglycolate, no mortality was observed in male and female New Zealand white rabbits receiving 200 mg/kg bw on the abraded skin (Griffiths and Koschier, 1979).

There were no valid inhalation studies for ammonium thioglycolate.

Justification for classification or non-classification

Based on an acute oral LD50 of 100 mg/kg bw in rats.

Classification:

Acute tox 3 - H301. Toxic if swallowed.