[Setting a maximum allowable concentration for urea in reclaimed potable water and evaluating the nature of its biological action].

The purpose of the study was to identify maxim allowable concentrations of urea in reclaimed potable water. The urea concentration equal to 80 mg/l is the threshold dose influencing the taste and flavor of water. Urea is a low toxicity substance (LD50 = 14,300 mg/kg), the effect of which is not cumulative.