The products of aqueous chlorination reactions of 1-methylnaphthalene, fluorene, dibenzofuran, anthracene, phenanthrene, 1-methylphenanthrene, fluoranthene, and pyrene have been determined. The conditions employed for these reactions approximated those that might be encountered in water treatment facilities. Reactions at pH > 6 tended to produce oxygenated products (epoxides, phenols, quinones, etc.), and reactions at pH < 6 tended to produce both oxygenated (quinones) and chlorinated products.