Metal concentrations in the sewage, effluents, and sludges of some southern Ontario wastewater treatment plants.

Aluminum, barium, berylliu, bismuth, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, silver, strontium, vanadium and zinc concentrations in the sewage, effluents and sludges of ten southern Ontario wastewater treatment plants are reported. The efficiency for metal removal by a conventional activated sludge plant was determined. The effect of metal concentrations in receiving waters from residual metals in sewage effluents is discussed. The environmental hazards of disposing of sewage sludges with high metal content on agricultural land is considered.