Heavy metals in the waste and in the water discharge area of municipal solid waste

Abstract

The county of Paranaguá discards 80 tons of municipal solid waste (MSW) daily in the Embocuí landfill without proper treatment. The present study aimed to evaluate the concentration of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb) and mercury (Hg) in the dump area and to compare it with reference values for soil and water quality stipulated by CETESB (2005). The methodology of the study involved the collection of waste samples (organic waste mixed with soil) from a depth of 1 m deep at 12 points of the dump, and the collection of water samples from a depth of 3 m at 3 points in the deposited waste. Extraction of heavy metals in the water samples was performed according to the USEPA (1999) method and analysis followed ICP-OES (Inductively Coupled Plasma - Atomic Emission Spectrometry). Analysis of the solid waste samples showed the following concentrations: (mg kg -1): As < 10; Cd < 1; Cr = 26; Pb = 52; e Hg = 0.2. The water samples showed the following concentrations: (mg L- 1): As < 5; Cd < 5; Cr =29 e Pb = 10. The amounts of heavy metals in samples of tailings and water from the landfill area fall below the values considered to create a risk of contamination.