Alternatives to Cs for Pb dating validation in south America and in the Carribean region: Point and diffuse sources.

As today the Cs fallout peak, in sediment cores, corresponds only to 25% of its initial concentration, alternatives to the use of Cs as aPb sediment dating validation tool are proposed. In highly industrialized bays, such as Guanabara Bay in the Rio de Janeiro metropolitan region, several chemical/compounds from the surrounding industry releases may be applied as validation tools. Chromium and copper profiles in a sediment core adequately fit the expected pattern due to the implementation of a chemical plant in 1958, reaching their maximum discharge in 1982 and subsequently decreasing due to the operation of a new wastewater treatment plant.

HCH distribution and microbial parameters after liming of a heavily contaminated soil in Rio de Janeiro.

The closing down of a lindane factory near Rio de Janeiro, over 45 years ago, left an area heavily contaminated with hexachlorocyclohexane (HCH). Remediation by soil liming was applied by government authorities in 1995. This study aims to evaluate the HCH distribution and impact on soil microbiota due to contamination and liming.