Abstract Various environmental chemicals are metabolised to chemically reactive sulfuric acid esters, which may covalently bind to cellular macromolecules and induce mutations and tumours. This activation pathway is usually not taken into account in external xenobiotic- metabolising systems used in short-term tests. We therefore analysed the abilities of cytosols from mammalian cell lines to activate benzylic alcohols (1-hydroxymethylpyrene and 9- ...