Genotoxic potential of organic extracts from municipal reclaimed water in Tianjin,China

Despite increasing pressure to make more efficient use of water resources, the widespread use of reclaimed water still remains a contentious issue, primarily because of risks to human health arising from water pollution by organic compounds. Therefore, safety evaluation of reclaimed water is an urgent need. The aim of this study was to determine the genotoxic potential of reclaimed water during low and high water periods. Reverse phase C-18 solid-phase extraction (RP-C18SPE) was used for the extraction of organic compounds from water samples. The tests, namely, Ames, micronucleus and chromosome aberrations were used to determine the damage caused by water samples on genetic material. Ames tests showed that both influent and effluent reclaimed water, except influent after metabolism by S9 in high water period, induced mutation of TA98 and TA100 strains of Salmonella typhimurium in a concentration-response manner. There were no significant differences in micronucleus and chromosome aberration tests. Even after treatment, reclaimed water in Tianjin still showed mutational effects and new strategies for reduction of genotoxins need to be considered.