Formation of chlorinated PAH--a possible health hazard from water chlorination

Four PAH compounds, fluorene, anthracene, fluoranthene and benzo(a)pyrene were dissolved in humus poor (lake) and humus rich water. The samples were chlorinated, stored for three days, and extracted with cyclohexane. Chlorinated derivatives of the four compounds were synthesised and used as calibration standards for quantitative analysis of the corresponding chlorinated PAH formed during the experiment. The synthesized chlorinated PAH were tested for mutagenic activity by the Ames test, and their octanol/water partition coefficient (Pow) were determined by thin layer chromatography. Chlorinated fluorene, fluoranthene and benzo(a)pyrene were formed during chlorination of PAH polluted lake water, but not during chlorination of the humus rich water samples. All chlorinated PAH except 9,10-dichloroanthracene, acted as strong mutagens both in the presence and in the absence of metabolic activation, while benzo(a)pyrene was the only mutagen active parent PAH. The determined Pow showed high lipophilicity for all chlorinated PAH. Theoretically determined bioconcentration factors (BCF) were found to be extremely high, and increased with increasing ring number and increasing number of chlorine atoms attached to the ring.