Facts About Various Types Of Pollution
pollution kills and estimated 2.7 million to 3.0 million people every year about
6% of all deaths annually. About 9 deaths in every 10 due to air pollution take
place in the developing world, where about 80% of all people live.
2.5 billion people, almost all in developing countries, suffer from high levels
of indoor air pollution. Indoor air pollution is due to burning wood, animal
dung, crop residues, and coal for cooking and heating. Most of the victims of
indoor pollution are women and girls, who have primary responsibility for cooing
and tending the house.
air pollution harms more than 1.1 billion people, mostly in cities. The World
Health Organisation (WHO) estimates that about 700,000 deaths annually could be
prevented in developing countries if three major atmosphere pollutants carbon
monoxide, suspended particulate matter, and lead were brought down to safer
levels. The direct health cost of urban air pollution in developing countries
was estimated in 1995 at nearly US $ 100 billion a year. Chronic bronchitis
alone accounted for around US $40 billion.
cities that lack pollution controls, millions of people are at risk from outdoor
pollution. Densely populated and rapidly growing cities such as Bangkok, Manila,
Mexico City and New Delhi are often entombed in a pall of pollution from trucks
and cars and from uncontrolled industrial emissions. In 1995, for example, the
average ozone concentration in Mexico City was about 0.15 parts per million, 10
times the natural atmospheric concentration and twice the maximum permitted in
Japan or the US. Ozone is a powerful secondary pollutant formed when oxides of
nitrogen and unburned volatile organic hydrocarbons, mostly from vehicle
exhausts, combine with oxygen under the action of sunlight. Ozone is a main
component of smog.
powerful secondary pollutant is acid rain, formed when sulfur dioxide and oxides
of nitrogen combine with water vapor and oxygen in the presence of sunlight to
form a diluted “soup” of sulfuric and nitric acids. They can fall as both
wet (acid rain) or dry deposition. Other harmful pollutants include sulfur
dioxide, suspended particular matter (soot, ash, and smoke from fires), carbon
monoxide from vehicles exhaust, and lead, mainly from the exhaust of vehicles
that burn leaded gasoline.
pollution is not only a health hazard but also reduces food production and
timber harvests, because high levels of pollution impair photosynthesis. In
Germany, for example, about US $ 4.7 billion a year in agricultural production
is lost to high levels sulfur, nitrogen oxides, and ozone.
2.3 billion people suffer from diseases linked to water. Providing safe drinking
water and adequate sanitation would have major health benefits. Some benefits
include and estimated 2.1 million fewer deaths from diarrhoeal diseases, 150
million fewer cases of schistosomiasis, and 75 million fewer cases of trachoma.
borne diseases, also known as “dirty water” disease, result from using water
contaminated by human, animal, or chemical wastes. These diseases cause an
estimated 12 million deaths a year, 5 million of them from diarrhoeal diseases.
Most of the victims are children in developing countries.
many places both surface and ground waters are fouled with industrial,
agricultural, and municipal wastes. According to the World Commission on Water
for the 21st Century, more than half of the World’s major rivers are so
depleted and polluted that they endanger human health and poison surrounding
ecosystem. In many large cities in the developing world the drinking water
supply is contaminated. Only half of Southeast Asia’s 550 million people have
access to safe drinking water.
from Heavy Metals
traced to heavy metals date back to ancient Rome, where lead pots, pipes, and
smelters were held responsible for loss of intelligence among children and for
brain damage and abnormal behaviour among adults. Heavy metals released into the
environment today come from uncontrolled emissions by metal smelters and other
industrial activities, unsafe disposal of industrial wastes, and lead in water
pipes, paint and gasoline.
heavy metals most dangerous to health include lead, mercury, cadmium, arsenic,
copper, zinc, and chromium. Such metals are found naturally in the soil in trace
amounts, which pose few problems. When concentrated in particular areas,
however, they present a serious danger. Arsenic and cadmium, for instance, can
cause cancer. Mercury can cause mutations and genetic damage, while copper,
lead, and mercury can cause brain and bon damage.
additives in gasoline cause widespread health problems in some countries. In
Thailand, for example, a 1990 study found that some 70,000 children in Bangkok
risked losing four or more points of IQ (Intelligence Quotient, based on
standardized tests) because they were heavily exposed to lead emissions from
motor vehicles. In Latin America some 15 million children under the age of two
are at risk of ill health from lead pollution.
the US leaded gasoline began to be phased out after the passage of the Clean Air
Act in 1970. It was not until the mid 1980s, however, that the European
Community followed suit. Elsewhere, leaded gasoline continues to be used
Source: The Bangladesh Observer,September 16, 2001