Dimethyl sulphate

Endpoint summary

Description of key information

EU RISK ASSESSMENT – DIMETHYL SULPHATE

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Additional information

Skin

In rabbits (number unknown) DMS was applied undiluted to the back for 1, 5, or 15 minutes. Scoring was carried out after 24 hours and after 8 days. Application for 1 minute caused no effects. Five minutes of treatment induced slight erythema at 24 hours, but after 8 days the effect had disappeared. After the 15 minutes application period slight erythema was seen after 24 hours; strong erythema and slight oedema were reported after 8 days. Scores in this study are not according to EC-guidelines, but the effects are classified using an in-house (BASF) scoring system (BASF, 1968).

When applied for 20 hours to the back of rabbits (number not indicated) DMS, undiluted, caused severe necrosis, severe oedema and very strong erythema after 24 hours. After 8 days very severe necrosis with ulceration was found. DMS was also applied to rabbit’s ears for a period of 20 hours. Twenty-four hours later very strong erythema, extensive necrosis, and strong oedema was scored (BASF-scoring system). The effect seen 8 days after application of DMS to the ear was indicated as mummification (BASF, 1968).

Despite the fact that the above-mentioned studies were not performed according to current guidelines, they allow DMS to be considered as corrosive.

 

Eyes

In a limited report DMS was found to be irritating to rabbit's eyes. The dose applied was 0.05 ml, which is considered to be too low according to EC-guidelines. After 1 hour eyes were totally swollen. After 24 hours very strong oedema, strong redness, and corneal opacity were reported.

Even after 8 days strong redness, corneal opacity, and strong chemosis with suppuration and staphyloma remained (BASF 1968). Despite the limited report this study indicates that DMS should be considered as an eye irritant with risk for serious damage to the eyes. Guillot (1982) further investigated the irritating potencies of DMS. Six rabbits were observed after 1 hour, 1, 2, 3, 4, and 7 days. DMS (0.1 ml) was applied with and without rinsing the eyes after treatment.

The result presented as an acute ocular irritation score (the most severe of the mean score per treatment group) justifies the classification extremely irritating. The effects observed are in agreement with the conclusion of the above-mentioned study.

 

Respiratory tract

DMS (3.7 or 6.3 mg/m3) is considered irritating to the respiratory tract in rats based on the limited reported repeated-dose study of Frame (1993)

Effects on skin irritation/corrosion: corrosive

Effects on eye irritation: highly irritating

Effects on respiratory irritation: irritating