GEO Brasil - UNEP

ecreational activity In addition to that, their appearance is
not appealing and they usually have an unpleasant smell It
is a problem common to almost every major city
The larger rivers and basins that receive urban effluents
have a greater dilution capacity and usually do not present
an unpleasant smell However, they have high
concentrations of pollutants that make them unfit for
bathing, reduce fishery production and damage valuable
ecosystems, such as mangrove marshes The Paraíba do
Sul River, which crosses three states (São Paulo, Rio de
Janeiro and Minas Gerais), the Capiberibe River, in Recife
(State of Pernambuco), and the Guaíba River, in Porto Alegre
(State of Rio Grande do Sul) are some examples of this
situation Except in places with high concentrations of heavy
metals and industrial toxic pollutants, the water can be
treated for residential supply at a modest cost
The nutrients of wastewater and residual water from
agricultural areas penetrate lakes, reservoirs and basins,
might lead to the production of toxic algae that threaten the
supply of potable water Guanabara Bay, in Rio de Janeiro,
is an exemplary case of a seabed deeply affected by the
phenomenon
construction of interceptors or the conversion of these
channels into covered sewage channels are actions aimed
at improving environmental quality Many oceanic beaches
in Brazil represent an important economic asset, due to
their high touristic value and potential Nevertheless, they
are threatened by pollution, which requires an improved
local collection and disposal system In some cases, this
includes building oceanic sewage interceptors
The quality parameters of the urban waters, presented in
Table 13 are state indicators of the environment in some
selected Brazilian localities
11410 Air Quality
The regions with the most acute air pollution problems are
the country’s metropolitan areas – notably São Paulo, Rio
de Janeiro, Belo Horizonte, Salvador, Recife, Porto Alegre
and Curitiba
Automotive vehicles are responsible for the highest rates
of pollutant emissions in the cities, specially in areas with
frequent thermal inversions These emissions are more
important than is suggested by emission inventories, as
they are closer to the surface and consist of finer particulates
than typical industrial emissions
the state of the environment in Brazil
As for the industries, there are many options for reducing
emissions by means of pollution prevention and
minimisation of residues at a cost considerably lower than
treating wastewater of industrial effluents Although these
lower-cost measures should be encouraged, they will be
insufficient to solve problems related to water pollution,
since industrial emissions are responsible for only 15 percent
of the total organic load in most cities (World Bank, 1998)
The necessary levels of effluent treatment should be
established according to the pollutants, the polluters, and
specific places Heavy metal and toxic pollutants limit
drastically the use of the water and they generally cause
long-term or irreversible damages The pollutants that
constantly exceed the acceptable limits include phenol,
mercury, oil and grease Strict control should take place at
the source, specially for industrial sources, in order to
achieve goals of desirable water quality
The open sewerage in urban areas causes a loss of amenities
and can induce disease vectors In these cases, the
Table 14 - Air quality in selected cities
Season averages during various periods of time PM 10
(g/m 3 )
WHO directives and environmental standard for the
Annual average
50
Metropolitan area of São Paulo (SP) 70
Cubatão (SP) 90
Rio de Janeiro (RJ)(Basin III) 88
Belo Horizonte (MG) 37
Contagem (MG) 48
Betim (MG) 40
Porto Alegre (RS) 54
Volta Redonda (RJ) 66
Source:
World Bank - 1998
The parameters presented for some Brazilian cities below
are indicators of the state of the environment in terms of air
quality
SO
(g/m 3 )
40
20
15
38
n.a.
25
13
23
n.a.
195