208
R.V. Marins et al.
I 44°j()'W
Magaratiba
nos
Sepetiba Bay
Industrial areas
Atlzmtic Ocelln
•
Water treatment plant
Fig. 1. Map showing location of the study site. Major urba n centres (_) and industri al areas
2500 mm, depending on location along the coast. Nine rivers draining the
quaternary plain at the northeastern coast of the Bay are responsible for almost
the totality of freshwater inputs, reaching an annual flow of 5.7 to 7.6 million m 3 •
Therefore annual atmospheric precipitation over Sepetiba Bay (0.5 to 10 x 10 7
m 3 a- I) equals and may even surpass the fluvial inputs, increasing the importance
of atmospheric derived pollutants such as Hg (Lacerda et al. 1988; Watts 1990;
Barcellos 1995).
The lowlands of the eastern coast of Sepetiba Bay, with good transport
facilities, cheap and ample land, good freshwater supply and low population
density, became interesting to industrial development, further facilitated by the
building in the late 1970'S of large harbour facilities. The population of the
Sepetiba Bay basin has risen from 600000 in 1978 to 1.2 million, concentrating
mostly along the northeastern portion as a result of industrial growth. This fast
and unplanned development resulted in high contamination of the bay, in direct
conflict with the necessity of environmental conservation and the sustainable
utilization of the bay's natural resources (Barcellos and Lacerda 1994).
Mercury in both inorganic as well as organic chemical forms is known to be
widely distributed in the environment. It can reach the coastal environment
through many routes such as river inputs, runoff and tides. However, dry and wet
atmospheric deposition is frequently the major route of Hg to coastal
environments (Miller and Buchanan 1979; Mignon 1993). The atmospheric
processes may also significantly affect the global distribution of Hg and provide a
means for Hg transfer between the continents and oceans (Mason et al. 1994).
There are few studies dealing with the fate of Hg in Sepetiba Bay. Recent
investigations showed increasing Hg concentrations along sediment cores taken
from the eastern shore of the Bay, indicating a progressive Hg accumulation in
R.V. Marins et al.
I 44°j()'W
Magaratiba
nos
Sepetiba Bay
Industrial areas
Atlzmtic Ocelln
•
Water treatment plant
Fig. 1. Map showing location of the study site. Major urba n centres (_) and industri al areas
2500 mm, depending on location along the coast. Nine rivers draining the
quaternary plain at the northeastern coast of the Bay are responsible for almost
the totality of freshwater inputs, reaching an annual flow of 5.7 to 7.6 million m 3 •
Therefore annual atmospheric precipitation over Sepetiba Bay (0.5 to 10 x 10 7
m 3 a- I) equals and may even surpass the fluvial inputs, increasing the importance
of atmospheric derived pollutants such as Hg (Lacerda et al. 1988; Watts 1990;
Barcellos 1995).
The lowlands of the eastern coast of Sepetiba Bay, with good transport
facilities, cheap and ample land, good freshwater supply and low population
density, became interesting to industrial development, further facilitated by the
building in the late 1970'S of large harbour facilities. The population of the
Sepetiba Bay basin has risen from 600000 in 1978 to 1.2 million, concentrating
mostly along the northeastern portion as a result of industrial growth. This fast
and unplanned development resulted in high contamination of the bay, in direct
conflict with the necessity of environmental conservation and the sustainable
utilization of the bay's natural resources (Barcellos and Lacerda 1994).
Mercury in both inorganic as well as organic chemical forms is known to be
widely distributed in the environment. It can reach the coastal environment
through many routes such as river inputs, runoff and tides. However, dry and wet
atmospheric deposition is frequently the major route of Hg to coastal
environments (Miller and Buchanan 1979; Mignon 1993). The atmospheric
processes may also significantly affect the global distribution of Hg and provide a
means for Hg transfer between the continents and oceans (Mason et al. 1994).
There are few studies dealing with the fate of Hg in Sepetiba Bay. Recent
investigations showed increasing Hg concentrations along sediment cores taken
from the eastern shore of the Bay, indicating a progressive Hg accumulation in