2. Pollution is the introduction of contaminants into the
natural environment that cause adverse
change. Pollution can take the form of chemical
substances or energy, such as noise, heat or
light. Pollutants, the components of pollution, can be
either foreign substances/energies or naturally occurring
contaminants. Pollution is often classed as point
source or nonpoint source pollution.
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4. Water pollution is the contamination of water bodies
(e.g. lakes, rivers, oceans, aquifers and groundwater). Water pollution
occurs when pollutants are discharged directly or indirectly into water
bodies without adequate treatment to remove harmful compounds.
Water pollution affects plants and organisms living in these bodies of
water. In almost all cases the effect is damaging not only to
individual species and populations, but also to the natural biological
communities.
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5. Air pollution is the introduction into
the atmosphere of chemicals, particulates, or biological materials that cause
discomfort, disease, or death to humans, damage other living organisms such as
food crops, or damage the natural environment or built environment.
The atmosphere is a complex dynamic natural gaseous system that is essential to
support life on planet Earth. Stratospheric ozone depletion due to air pollution
has long been recognized as a threat to human health as well as to the
Earth's ecosystems.
Indoor air pollution (see Airlog) and 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.
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6. Land pollution is the degradation of the Earth's land surface
through misuse of the soil by poor agricultural
practices, mineral exploitation, industrial waste
dumping, and indiscriminate disposal of urban wastes. It
includes visible waste and litter as well as pollution of the
soil itself.
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