Use human breast cancer cells to examine change of estrogenic in drinking water treatment process

Endocrine disrupters (EDCs) have caused great concerns for the safety of water environment and drinking water in recent years. This paper uses lab-cultured human breast cancer cells (MCF-7) to examine the changes of water estrogenicity during the drinking water treatment process and uses chemical analysis as supplementary information. The results showed that MCF-7 were extremely sensitive to the aqueous estrogenicity; cell proliferation by 17-β Estradio (E2) was observed at concentration as low as 10-14 mol/1. Overdose might cause poisoning of cell, which led to the cell decrease instead of proliferation. The source water of Songhua River showed significant estrogenicity, which was effectively controlled by regular drinking water treatment process. Coagulation-sedimentation was very effective in decreasing the water estrogenicity and almost eliminated the proliferation effect of the source water, the filtration step, on the other hand, increased the water estrogenicity by almost 10%; the final disinfection then reduced the estrogenicity to the normal level. The overall effect was that the finished water was safe in terms of estrogenicity though the source water was unsafe.