Reaction mass of methyl chloroacetate and chloroacetic acid

Endpoint summary

Description of key information

Acute oral toxicity: 
Reaction mass of methyl chloroacetate and chloroacetic acid: Data waiving: According to column 2 of REACH Annex VII, the study does not need to be conducted since the substance is classified as corrosive to the skin. 
Monochloroacetic acid: Key study: Test method was similar to OECD guideline 401. The oral LD50 is 90.4 mg/kg body weight. 
Methyl chloroacetate: Key study: Test method was similar to OECD guideline 401. The oral LD50 is 107 mg/kg body weight. 
Acute inhalation toxicity: 
Reaction mass of methyl chloroacetate and chloroacetic acid: Data waiving: According to column 2 of REACH Annex VIII, the study does not need to be conducted since the substance is classified as corrosive to the skin. 
Monochloroacetic acid: No data on test method and no data on the duration of the exposure. The LC50 is 0.18 mg/l (supporting study). 
Methyl chloroacetate: Key study: OECD guideline 403. The 4-h LC50 in rats was determined to be between 210 and 315 ppm (638 and 957 mg/m3). 
Acute dermal toxicity: 
Reaction mass of methyl chloroacetate and chloroacetic acid: Data waiving: According to column 2 of REACH Annex VIII, the study does not need to be conducted since the substance is classified as corrosive to the skin. 
Monochloroacetic acid: Key study: Test method was similar to OECD guideline 402. The dermal LD50 is 305 mg/kg body weight. 
Methyl chloroacetate: Key study: Test method was similar to OECD guideline 402. The dermal LD50 is 137 mg/kg body weight. 

Additional information

Reaction mass of methyl chloroacetate and chloroacetic acid:

1.- Monochloroacetic acid:

According to column 2 of REACH Annex VII, the acute toxicity studies do not need to be conducted since the substance is classified as corrosive to the skin. Futhermore, the substance is included in the harmonised classification and labelling list and it is classified as follows:

According to the CLP Regulation:

Acute oral toxicity: Acute category 3 (minimum classification)

Acute dermal toxicity: Acute category 3 (minimum classification)

Acute inhalation toxicity: Acute category 3 (minimum classification)

According to the Directive 67/548/EEC:

T, R23/24/25

An oral LD50 in rat of 90.4 mg/kg bw is available from a key study. This value supports the classification as Acute oral toxicity category 3.

For the acute inhalation toxicity of the substance monochloroacetic acid, there is no reliable information. An LC50 value of 0.18 mg/l is reported. However, no data on test method and no data on the duration of the exposure is provided.

A dermal LD50 in rat of 305 mg/kg bw is available from a key study. This value supports the classification as Acute dermal toxicity category 3.

2.- Methyl chloroacetate:

Acute oral toxicity: key study in rats which is considered the relevant species for acute oral toxicity classification. Although no guideline was followed, the test method was similar to OECD 401. The oral LD50 is 107 mg/kg body weight. These results support the classification of the substance in the Acute toxicity Category 3 (oral).

Acute dermal toxicity: one study in rats and one study in rabbits. Both species are considered relevant for acute dermal toxicity classification. Therefore, the lowest effect level has been determined as the key study in order to be used for classification in the most severe category. The lowest dermal LD50 (137 mg/kg bw) was observed in rats and supports the classification of substance in the Acute toxicity Category 2 (dermal).

Acute inhalation toxicity: key study in rats which is considered the relevant species for acute inhalation toxicity classification. The OECD guideline 403 was followed. The 4-h LC50 in rats was determined to be between 210 and 315 ppm (638 and 957 mg/m3). These results support the classification of the substance in the Acute toxicity Category 2 (inhalation).

Justification for classification or non-classification

Monochloroacetic acid:

Acute oral toxicity: Acute category 3

Acute dermal toxicity: Acute category 3

Acute inhalation toxicity: Acute category 3 (minimum classification)

Methyl chloroacetate:

Acute oral toxicity: Acute category 3

Acute dermal toxicity: Acute category 2

Acute inhalation toxicity: Acute category 2

Methanol (impurity present in the reaction mass):

The substance is included in the harmonised classification and labelling list and it is classified as follows:

According to the CLP Regulation:

Acute oral toxicity: Acute category 3 (minimum classification)

Acute dermal toxicity: Acute category 3 (minimum classification)

Acute inhalation toxicity: Acute category 3 (minimum classification)

STOT SE 1 (Specific concentration limits: STOT SE 1: C ≥ 10%; STOT SE 2: 3% ≤ C < 10%).

Conclusions:

Based on the acute toxicity data for the substances mentioned above and their concentrations, the following classification is proposed following the classification criteria for mixtures included in the CLP Regulation:

Acute oral toxicity: Acute category 3

Acute dermal toxicity: Acute category 2

Acute inhalation toxicity: Acute category 2