LEAD, CADMIUM AND ZINC ACCUMULATION ON SOIL AND VEGETATION ALONG SOME SELECTED MAJOR ROADS OF EASTERN CAPE

摘要

Surface soil and grass samples were collected in triplicates from seven locations perpendicular to three major roads in Eastern Cape. Total and available lead, cadmium and zinc were determined in the soil samples and total elements were determined in grass. Lead, cadmium and zinc concentrations declined with distance from road traffic. Significant correlation was also established between available elements in soil and in grass. Levels of total and available elements in the soils ranged from 1167-10834 μg g~(-1) and from 200- 5734 μg g~(-1), respectively. The levels of the element in grass varied between 200 μg g~(-1) and 3900 μg g~(-1). Total and available cadmium levels in soil although lower than the levels are also significant with values ranging from 17-2833 μg g~(-1) and from 27 μg g~(-1) and from 27-1867 μg g~(-1), respectively. The cadmium levels in grass varied between 7 μg g~(-1) and 1100 μg g~(-1). The total and available zinc levels in soil ranged from 2833-8334 μg g~(-1) and from 533-3600 μg g~(-1). The levels in grass varied between 0 and 2800 μg g~(-1). The degree of pollution measured would constitute a threat to livestock. Motor traffic appears to be the main source of the elements.