GEO Brasil - UNEP

the State of Activities in Marine and Coastal Areas
6
Discharges into the Sea
the state of the environmet in Brazil
According to Agenda 21, marine
environmental degradation may
result from various sources In
average, 70 percent of sea pollution
comes from the land, 10 percent from
maritime transport and 10 percent
from discharges into the sea
However, the magnitude of these
interactions may vary according to
the size of water basins, sediment
collectors and polluting residues over
vast areas
According to O Vidal and W Rast,
around 80 percent of sea
contamination is caused by human
activities on the land, such as
urbanisation, agriculture, tourism,
industrial development, discharge of
untreated sewage, industrial waste
and lack of coastal infrastructure
The oceans receive a significant part
of all pollutants thrown into the rivers,
in addition to urban and industrial
rubbish produced near the coast
Similarly, the pollution caused by
domestic sewage and industrial waste
affects estuarine ecosystems,
especially mangrove swamps, a fact
which contributes to the drop in fishery
outputs Petrochemical and
chlorochemical complexes are present
at most large estuaries and throw heavy
metals and oil residues into mangrove
swamps and the continental platform
The environmental threat posed by
these pollutants will depend on
different national or regional
conditions The final destinations of
polluting agents are estuaries, coastal
lagoons, bays and the ocean
GERCO’s report informs that over three thousand tonnes of liquid pollutants are
discharged in various points along the Brazilian coast every day, in addition to
large quantities of industrial and organic waste Four states receive the greatest
volumes of industrial toxic elements: Rio de Janeiro, Bahia, São Paulo and Espírito
Santo
The humid and coastal areas in the Northeast have been suffering a high degree
of environmental degradation The effluents thrown into the ocean through
underwater sewage pipelines cause serious problems because they are discharged
in an area known by local fishermen as the “Great Mud”(“Lama Grande”), the
main shrimp habitat around the city of Maceió, capital of the State of Alagoas
In Bahia, 95,501 tonnes of industrial waste is discarded in the ocean, 41,128 of
which are toxic The All Saints’ Bay is, in fact, contaminated with mercury In Rio
de Janeiro, the toxic contamination numbers are 119,600 and 64,000, respectively
Every day, 500 tonnes of organic sewage, 50 tonnes of nitrates and heavy metals,
|and 3,000 tonnes of solid residues (sand, plastic, cans and other rubbish) are
discarded into the Guanabara Bay Important industrial and agricultural activities
concentrated in Rio Grande and Pelotas, in the south of Brazil, also contaminate
the Laguna dos Patos estuary, in addition to the pollution produced by port
activities in that state
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