Trace metal distribution in surface soil in the area of a municipal solid waste landfill and a medical waste incinerator

摘要

Environmental studies have prompted interest in the determination of metals in surface soil that can be considered the major recipient of pollutants (Alumaa et al., 2002). Because of their capacity to enter the food chain through soil and plants, metals are considered environmental indicators (Hamilton, 1995; Morselli et al., 2002). Therefore, special attention should be paid to the metal levels in soil in the vicinity of municipal solid waste landfills and medical waste incinerators. In Brazil, about 228,413 ton/day of urban solid waste are generated all over the country today (IBGE, 2000) and 72% of this volume is being dumped without any previous treatment. Only 17% is going to planned landfill sites, while 11% is going to treatment facilities. In Riberrao Preto, Sao Paulo State, Brazil, a municipal landfill site (MLS) for urban waste disposal integrated with a medical waste incinerator plant (MWIP) has been operating since 1989. At present, the MLS is receiving 500 ton/day of solid waste, while the MWIP is processing 9 ton/day of health services waste. This volume is generated by approximately 519,000 inhabitants. The purpose of the present study was to determine the levels of Cd, Cr, Pb, Mn, Zn, Cu and Hg in soils collected in the area of a Ribeirao Preto MLS-MWIP.