Air Pollution
Air pollution is the contamination of air due to the
presence of substances in the atmosphere that are harmful to
the health of humans and other living beings, or cause
damage to the climate or to materials. It is also the
contamination of indoor or outdoor surrounding either by chemical activities,
physical or biological agents that alters the natural features of the
atmosphere. There are many different types of air pollutants, such as
gases (including ammonia, carbon monoxide, sulphur dioxide, nitrous
oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both
organic and inorganic), and biological molecules. Air pollution can cause
diseases, allergies, and even death to humans; it can also cause harm to other
living organisms such as animals and food crops, and may damage the natural environment
(for example, climate change, ozone depletion or habitat
degradation) or built environment (for example, acid rain). Air
pollution can be caused by both human activities and natural phenomena.
Air quality is closely
related to the earth's climate and ecosystems globally. many of the
contributors of air pollution are also sources of greenhouse emission i.e.,
burning of fossil fuel.
Air pollution is a
significant risk factor for a number of pollution-related
diseases, including respiratory infections, heart disease, COPD, stroke and lung
cancer. [Growing evidence suggests that air pollution exposure may be
associated with reduced IQ scores, impaired cognition, increased risk for
psychiatric disorders such as depression and detrimental perinatal health.] The human health effects of poor air quality are
far reaching, but principally affect the body's respiratory system and
the cardiovascular system. Individual
reactions to air pollutants depend on the type of pollutant a person is exposed
to, the degree of exposure, and the individual's health status and
genetics.
Outdoor air pollution
attributable to fossil fuel use alone causes ~3.61 million deaths annually,
making it one of the top contributors to human death, with
anthropogenic ozone and PM2.5 causing ~2.1 million. Overall,
air pollution causes the deaths of around 7 million people worldwide each year,
or a global mean loss of life expectancy (LLE) of 2.9 years, and is the
world's largest single environmental health risk, which has not shown
significant progress since at least 2015. Indoor air pollution and poor urban air
quality are listed as two of the world's worst toxic pollution
problems in the 2008 Blacksmith Institute World's Worst Polluted
Places report. The scope of the air pollution crisis is large: 90% of the
world's population breathes dirty air to some degree. Although the health
consequences are extensive, the way the problem is handled is considered
largely haphazard or neglected.
Productivity losses and
degraded quality of life caused by air pollution are estimated to cost
the world economy $5 trillion per year but, along with health
and mortality impacts, are an externality to the contemporary economic
system and most human activity, albeit sometimes being moderately regulated
and monitored. Various pollution control technologies and strategies are
available to reduce air pollution. Several
international and national legislation and regulation have been developed to
limit the negative effects of air pollution.
Local rules, when properly executed, have resulted in significant
advances in public health. Some of
these efforts have been successful at the international level, such as
the Montreal Protocol, which reduced the release of harmful ozone depleting
chemicals, and the 1985 Helsinki Protocol, which reduced sulphur
emissions, while others, such as international action on climate change, have
been less successful.
https://en.wikipedia.org/wiki/Pollution
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