[ Pollutants: Biological pollutants ]

Biological pollutants are biodegradable substances which can be considered one of the 'cleanest' pollutants, however rate of accumulation currently in an area which is bigger than the rate of decomposition has made this an undisputable contributory factor to pollution.

Types

Characteristics

Uses

Effects

Soil pollutants

Sediments
Due to soil erosion on hill slope or coastline where loose soil practices are washed down and carried to streambed, lake or ocean

Organic matter
Addition of fertilizers and nutrients to promote plant growth and development, usually from urea and faecal matter of animals, or decomposition of dead organism.

-	decomposed matter provides fertility to soil for agriculture
-	sediments can be collected and used for construction of barriers

-	occurrence of landslip at hillslope
-	unbearable stench of decomposing is imminent
-	leeching of organic matter to streambed, lake or ocean, leading to eutrophication
-	depth of lake is reduced as a result of sedimentation
-	change in original geographical landscape

Water pollutants

Microorganism
Due to evolution and mutation microscopic organisms can be viral and transmit diseases to any living organisms consuming it, through secretion of poison

-	reduction in clarity of water in lakes
-	cause for malaria
-	cause for diarrhea due to contamination of drinking water
-	acne-like skin rash
-	deadly viral attack can cause death to living organisms

Air pollutants

Particulate matter
Due to volcanic eruption and evaporation of gases such as methane, sulfur dioxide, nitrogen dioxide and carbon dioxide from decomposing materials to the atmosphere which accumulates gradually and chemically reactive to react

-	atmospheric visibility reduce (haze, smog)
-	build up of toxic chemicals in the atmosphere harmful to living organisms
-	frequent asthma attack
-	adverse respiratory illness is imminent