The problems associated with the formation of halogen-containing compounds (HCC) during water chlorination are under consideration. It is indicated that their wide spread (in drinking and reservoir water, air, foodstuffs), the multitude of routes by which they enter the body (through the gastrointestinal tract, inspired air, and undamaged skin), their high toxicity, accumulation, and carcinogenic effects now determine the significance of HCC as a factor that constitutes a serious hazard to all contingents of the whole population of the country. Cardinal solution of the HCC-related problem is to ban chlorination of water, to expose it to UV, and to use other up-to-date safe modes of its decontamination.