The contamination of pasture by a lead smelter in a semi-arid environment

Abstract

A study was made of the extent of heavy metal contamination of pastures surrounding the lead and zinc smelters at Port Pirie, South Australia. The degree of contamination depended on species and distance from the smelter. Contamination of herbage by lead resulted mainly from adhering soil dust and by cadmium mainly from root uptake. Both mechanisms were important for zinc, but surface contamination was more important closer to the smelter. The implications of raised levels of zinc, lead and cadmium in herbage and soils on animal health are discussed. The animals most at risk are those kept within about 5 km of the smelter; that is, those yarded within the urban area and adjacent agricultural land,