1. Pollution
Pollution is harmful alteration of the natural state of a medium as a result of the introduction of
a completely alien to this environment (pollutant) agent, causing instability, disorder, harm or
discomfort in an ecosystem, on a physical medium, or a being of contaminant vivo.1 can be a
chemical substance, energy (as sound, heat, or light), or even genes. Sometimes the
contaminant is a substance strange, or a
form of energy, and at other times a
natural substance.
It is always a negative alteration of the
natural state of the environment, and is
usually generated as a result of human
activity is considered a form of
environmental impact.
Pollution can be classified depending on
the type of source of where it comes
from, or by the form of pollutant emitted
or environment that pollutes. There are many polluting agents including chemicals (such as
pesticides, cyanide, herbicides et al.), municipal waste, oil, or ionizing radiation. All of these
can cause diseases, damage to ecosystems and environment. There are also many gaseous
pollutants that play an important role in different atmospheric phenomena, such as the
generation of acid rain, the weakening of the ozone layer, global warming, and in general, on
climate change.