Chemical category approach of genotoxicity studies for branched alkylphenols.

A chemical category is a group of chemicals whose toxicological properties are expected to be similar or follow a regular pattern as a result of structural similarity. The category approach is beneficial for decreasing in the resource of risk assessment for huge amount of unevaluated existing chemicals, and also in the use of all kinds of animal tests including even in vivo genotoxicity tests from a point of view of the animal welfare. The present paper reports the results of in vivo micronucleus tests of o-sec-butylphenol (CAS:89-72-5) and 2-isopropyl-5-methylphenol (CAS:89-83-8) and discusses genotoxic potential of seven alkylphenols, o-sec-butylphenol, 2-isopropyl-5-methylphenol, p-sec-butylphenol (CAS:99-71-8), 2-tert-butylphenol (CAS:88-18-6), 2, 4-di-tert-butylphenol (CAS:96-76-4), 4-tert-butylphenol (CAS:98-54-4) and 6-tert-butyl-m-cresole (CAS:88-60-8) by the category approach.