Heavy metal contamination of vegetables and soil in domestic gardens around a smelting complex

Abstract

High levels of copper, zinc, lead, cadmium, nickel, and iron are reported in leaf vegetables grown in domestic gardens in close proximity to the copper smelter in Wollongong, New South Wales, Australia. Mean levels (dry matter weight) of lead, cadmium and nickel in lettuce are 23 ppm, 4·5 ppm, and 2·7 ppm, respectively. Easily-extractable levels of heavy metals in the supporting soil are also high. Significant correlations exist between distance from the main chimney of the smelter and the levels of a number of the metals in both soil and leaf vegetables (lettuce). In addition, highly significant correlations occur among the levels of most heavy metals in both soil and leaf vegetables.