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20 1. Air and ater Pollution W

Latin America
In Latin America, 75% of the population lives in large cities, producing sewage volumes far
higher than industrial ones. This high urbanization leel combined with the fact that only v
2% of domestic sewage is treated causes major problems to water supply and proliferation
of pathogenic diseases. The gold mining industry is also a major polluter and is responsible
for the presence of mercury in water. The extensive use of pesticides and fertilizers in agri-
culture poses another threat to water resources in Brazil, Colombia, and Ecuador .

Japan
Despite the strengthening of environmental policies, problems in relation to cadmium and
w
age,
cyanide, dioxin, organic pollution, lake eutrophication, residential se pesticide
ges,
runoff, industrial dischar and groundwater contamination by toxics and nitrates also
need to be tackled.
Australia and New Zealand
Nitrates and particularly phosphorus remain unacceptably high in Australia. Sedimentation
constitutes a problem in both Australia and New Zealand, with the situation improving due
v
w
to the remoal of sheep from steep pastures. Seage pollution has also been reduced
w because of the construction of seage treatment plants.
Asia

The situation is more complex in the region of Asia and the PWater quality has acif ic.
many enemies there. First, sedimentation constitutes a major cause of pollution in Asian
,
v
rivers, since sediment loads are four times the world aerage. Secondly hazardous and
toxic waste deteriorates the water quality. It is noteworthy that lead levels in Asia’s surface
water are about 20 times higher than those in OECD countries. Thirdly eutrophication is ,
xtensi
v
faced due to the ee use of fertilizers in the last 30 years. But the list of problems
does not end here. Asian rivers contain three times as many bacteria from human waste as
age and industrial the world average. Finally, urbanization and the release of untreated se w
waste to the environment are expected to cause seater pollution problems. ere w v
v Water pollution trends hae particularly worsened in China in recent years. The indus-
trial development (as certified from oil demand) and the intensive agriculture (China is the
world’s largest consumer of synthetic nitrogen fertilizers) pose a threat to water bodies.
Severe water problems are also faced in southeast Asia. For e Bangladesh and xample,
adjacent parts of India suffer from arsenic contamination of groundw. Specif , ater ically
arsenic poisoning of groundwater has affected more than 50% of the total area of
Bangladesh. The gradual introduction of arsenic inyo the food chain is more than a possi-
bility. Nitrate pollution is also a problem in these areas.
w
aste
The discharge of raw and partially treated water into the environment in the
Mashriq subregion (Iraq, Jordan, Lebanon, Syrian Arab Republic, the West Bank, and
Gaza) has deteriorated water quality and is a threat to public health.
In the est Bank and Gaza, the list of problems in connection to groundwater includes W
high pesticide levels, and nitrate concentrations four times the WHO limit. In some central