2. How is acute toxicity expressed?

Acute toxicity studies are mainly carried out on rodents (mice and rats) for oral and inhalation studies, and on rats or rabbits for dermal studies. Studies are conducted in accordance with internationally recognized Good Laboratory Practice (GLP) protocols.

International OECD protocols are to be preferred.

Generally, three or four increasing doses are determined and administered to groups of 3 to 5 animals per group:

• by intragastric gavage for the oral route (OECD n° 401, 420, 425);

• by application to a specific hair-free body surface for dermal application (0CDE no. 402);

• by exposure in a closed enclosure for 4 to 6 hours for inhalation (OECD n° 403, 433, 436).

Acute toxicity studies determine...