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Humans and their environment


A mountain of household and industrial rubbish

Pollution is the addition of substances to the environment that may be harmful to living organisms. Population growth and increases in the standard of living cause more waste to be produced. If this waste is not handled correctly, it leads to pollution. The most obvious form of pollution is often simply just litter on the ground, but pollution can affect the air and water too.

Land pollution

Most rubbish is buried in landfill sites and not all of it comprises safe materials. Even common household items can contain toxic chemicals such as poisonous metals. Many smoke alarms contain radioactive americium. Industrial waste is also discharged onto the land. Many farmers apply pesticidespesticides: chemicals used to kill insects, weeds and microorganisms that might damage crops to improve their crops, but these can damage living things. Toxic chemicals can be washed from the land into rivers, lakes and seas.

Water pollution

an oil slick spill on Haven beach

Oil spills cause a lot of harm to the environment, both at sea and on land

Water pollution is caused by the discharge of harmful substances into rivers, lakes and seas.

Many aquatic invertebrateinvertebrate: Animal without a backbone animals cannot survive in polluted water, so their presence or absence indicates the extent to which a body of water is polluted.

Some common water pollutants and their effect

pollutanttypical effect
fertilisersdamage to aquatic ecosystems
sewagekills aquatic organisms and harms human health
toxic chemicalskill aquatic organisms and harm human health

Back to Evolution and environment index

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