RESUMO
Mercury emissions to soil, waters, and the atmosphere in the Sepetiba Bay basin were estimated by means of emission factors and data base of major industrial and urban sources of Hg. This approach is the most effective in assessing pollutant loads from diffuse sources, as in the case of Hg in the Sepetiba Bay basin. Total Hg emission ranges from 20 to 364 kg yr(-1). A significant fraction of this input is to the atmosphere, ranging from 115 to 149 kg yr(-1) (41 to 58 per cent), mostly due to emissions from iron and steel production and an oil fired power plant. Inputs to soil range from 84 to 215 kg yr(-1) (42 to 59 per cent), mostly from an urban ladfill and from metal manufacturing. Direct inputs to surface water are small (<1.0 kg yr(-1). Estimated total and atmospheric emissions agree with measurements of atmospheric Hg deposition and with preliminary data on fluvial systems.