Rapid communication: water disinfection by-products enhanced apoptotic activity in human lymphocytes

The apoptosis-inducing activity of concentrated sediments of disinfected and non-disinfected water samples from the waterworks in Budapest, Hungary, was investigated using cultures of human peripherial blood lymphocytes. Chlorine-treated water and untreated (raw) water sediments were concentrated with the use of Amberlite XAD-2 resin columns. The concentrates were dissolved in dimethyl sulfoxide and added to cultures of human peripherial blood lymphocytes. Apoptotic index was determined in lymphocytes after treatment with the raw or disinfected concentrates by flow cytometry. Disinfected water concentrates of 100 microl/ml increased the apoptotic ratio of lymphocyte culture. The same amount of raw water concentrate also enhanced apoptosis. Both raw water and disinfected water contain substances that induced a significant rate of apoptosis in lymphocyte cultures.