Relative Importance of Non-Point Sources
of Mercury to an Industrialized Coastal System,
Sepetiba Bay, SE Brazil
R.V. MARINS, L.D. LACERDA, and R.C. VILLAS BOAS
1
Introduction
Estimation of Hg emissions to air, soil and water is the first step in the regional
management and control of areas where Hg contamination is potentially
significant and no clear point source of this metal exists, such as in diversified
industrial parks. Sepetiba Bay basin, SE Brazil, is an example of such a situation.
Over 400 industries, from oil-fired power plants to steel and non-ferrous metal
manufacturing to plastics and chemicals, have been installed in the region since
the late 1960s. Important point sources of metals such as Cd, Zn and Pb have
been identified and controlled during the past decade; no significant point source
of Hg, however, has been identified in the area. Notwithstanding, Hg is a
ubiquitous byproduct of many industries and is also frequently present in urban
and domestic wastes (Barcellos and Lacerda 1994; Marins et al. 1996).
With increasing control of known industrial point sources of metals, in
particular of Hg, diffuse sources become more important, receiving increasing
attention from the environmental authorities (Behrendt 1993; Pacyna 1995).
Although diffuse sources of Hg have not been correlated to human health,
measured concentrations of Hg in Sepetiba Bay atmosphere (Marins et al. 1996),
sediments (Quevauviller et al. 1992) and fish (Kehrig 1995) are doubtless
associated with anthropogenic sources of this metal. Diffuse sources are difficult
to control and Hg presents very long residence times in coastal waters, thus
progressive accumulation of Hg in the bay's biota may occur, with potential
health impacts on the local population, still highly dependent on local natural
resources.
2
Environmetal Setting of Sepetiba Bay
Sepetiba Bay is a semienclosed waterbody with approximately 420 km 2 of area
and average depth of 6 m, located at latitude 23°S and longitude 44°W, at
approximately 60 km south of Rio de Janeiro city (Fig. 1). The region is under a
hot-humid tropical climate, with mean annual precipitation ranging from 1400 to
Environmental Science
Mercury Contaminated Sites (ed. by R. Ebinghaus et al.)
© Springer-Verlag Berlin Heidelberg 1999
of Mercury to an Industrialized Coastal System,
Sepetiba Bay, SE Brazil
R.V. MARINS, L.D. LACERDA, and R.C. VILLAS BOAS
1
Introduction
Estimation of Hg emissions to air, soil and water is the first step in the regional
management and control of areas where Hg contamination is potentially
significant and no clear point source of this metal exists, such as in diversified
industrial parks. Sepetiba Bay basin, SE Brazil, is an example of such a situation.
Over 400 industries, from oil-fired power plants to steel and non-ferrous metal
manufacturing to plastics and chemicals, have been installed in the region since
the late 1960s. Important point sources of metals such as Cd, Zn and Pb have
been identified and controlled during the past decade; no significant point source
of Hg, however, has been identified in the area. Notwithstanding, Hg is a
ubiquitous byproduct of many industries and is also frequently present in urban
and domestic wastes (Barcellos and Lacerda 1994; Marins et al. 1996).
With increasing control of known industrial point sources of metals, in
particular of Hg, diffuse sources become more important, receiving increasing
attention from the environmental authorities (Behrendt 1993; Pacyna 1995).
Although diffuse sources of Hg have not been correlated to human health,
measured concentrations of Hg in Sepetiba Bay atmosphere (Marins et al. 1996),
sediments (Quevauviller et al. 1992) and fish (Kehrig 1995) are doubtless
associated with anthropogenic sources of this metal. Diffuse sources are difficult
to control and Hg presents very long residence times in coastal waters, thus
progressive accumulation of Hg in the bay's biota may occur, with potential
health impacts on the local population, still highly dependent on local natural
resources.
2
Environmetal Setting of Sepetiba Bay
Sepetiba Bay is a semienclosed waterbody with approximately 420 km 2 of area
and average depth of 6 m, located at latitude 23°S and longitude 44°W, at
approximately 60 km south of Rio de Janeiro city (Fig. 1). The region is under a
hot-humid tropical climate, with mean annual precipitation ranging from 1400 to
Environmental Science
Mercury Contaminated Sites (ed. by R. Ebinghaus et al.)
© Springer-Verlag Berlin Heidelberg 1999