Dimethyl sulphate

Endpoint summary

Description of key information

EU RISK ASSESSMENT – DIMETHYL SULPHATE

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

106 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

LC50

Value:

45 mg/m³ air

Additional information

Several studies have been carried out with different species and by different routes.

All data on acute toxicity of DMS are of limited quality. DMS has to be classified as toxic after oral treatment (based on the study of BASF, 1968). In inhalation studies the compound is found to be very toxic.

No signs of toxicity other than death are reported, except in the studies of Druckrey (1966), BASF (1968), and Batsura et al. (1980). Druckrey reports convulsions and dyspnoea in rats exposed to DMSand i.v. Autopsy revealed pulmonary oedema, hepatic congestion and intestinal bleedings. In the BASF study rats (p.o.) and mice (i.p.) were reported to experience dyspnoea and convulsions, rats were apathic and remained in a hunched posture. Autopsy showed gastrectasy and terminal lung oedema (BASF, 1968).

In an inhalation study by BASF (1968) rats (6-12 per group) were exposed to saturated DMS vapour (according to the rapporteur 592 ppm≈3100 mg/m3l, 20°C. However, this study of BASF is not suitable for the determination of a LC50.

In rats the LC50level after a 4 hr-inhalative exposure to DMS is reported to be 45 mg/m3. Groups of animals were sacrificed immediately following exposure and at intervals thereafter. The rats were dyspnoeic with cyanosis of the mucosae, hyperemia of the lung, and hemorrhage in the internal organs. Some animals had nasal discharge. Histological and electron microscopic examination of lung tissue revealed hemorrhage and coagulated proteins in the alveoli. After a latent period of 5-6 hr, accumulation of edematous fluid in the air spaces developed progressively over 24-48 hr (Batsura et al., 1980).