Pollution means any change in the environment affecting an ecosystem or a biosphere by physical, chemical or biological substances or by artificial radiation.
Mostly induced by humans, it affects air (atmospheric pollution), soil (soil or land pollution) and water (oceans, river, etc.), known as marine pollution. We also talk about noise pollution and eye pollution which are the results of air pollution.
Our atmosphere is perfectly balanced by nature which guarantees the continuity of life. The ecosystem can malfunction but for science nothing is done by chance. Human activities (industry, transport, electricity, etc.) release so-called greenhouse gases which can even destroy the ozone layer. These gases present anomalies or even toxic (excess of CO2, methane, nitrogen, etc.) inducing the premature death of living beings and therefore an imbalance in the ecosystem.
Health risks : respiratory complications (asthma), cardiovascular diseases, disturbances of brain activity, lung cancer …
Air pollution kills 7 million people a year. ( 2018’s statistics, World Health Organization)
Water pollution is the degradation of water quality due to the rejection of chemicals mainly untreated wastewater and the rejection of agriculture, affecting the groundwater and streams by runoff. The release of untreated hydrocarbons is an other cause.
Health risks : poisoning, infection, diarrhea, hepatitis, cholera …
Soil pollution and marine pollution are strongly linked. Soil pollution can have industrial or agricultural origins through the excessive use of pesticides which gradually infiltrates the soil. This local poisoning can spread over the long term over larger areas. The bad behavior of the Man towards his entourage is also a worrying factor.