Treatment of wastewater unavoidably results in the generation of huge quantities of sludge in which pollutants concentrate and which must be disposed of. The aim of this study was to compare the quality of organic matter, the metal composition and toxic organic content in different sewage sludge. The presence of these substances caused environmental damage in soil, plants, groundwater and air. Sewage sludge was periodically sampled from five treatment plant treated municipal and industrial wastewater in common in Almetevsk, Elabuga, Zainsk, Kazan, Chistopol (Tatarstan, Russia). Knowledge of the metal content of the sludge is a key step in selecting or in ruling out the various disposal alternatives. For the approval of possible utilization of sewage sludge as fertilizer the estimation of the chemical compounds has to be supplemented with the toxicity bioassay.