[Effectiveness of the biological purification of sewage for removing carcinogenic polycyclic aromatic hydrocarbons].

The correlation between biological purification of sewage and concentrations of carcinogens in it is studied. The balance between the income and outcome of benza(a)pyrene (BP) with water and surplus active mud of paper in aero-tanks, performed under both industrial and laboratory conditions is examined. It is demonstrated that BP is not destroyed by biological purification but is accumulated by the active sludge cells. Thus, the biologic purification of sewage prevents from pollution by carcinogenic polycyclic hydrocarbons, but does not remove these agents from the environment.