WATER POLLUTION

 

 

        Water pollution is the contamination of water bodies such as lakes, rivers, oceans, and groundwater caused by human activities, which can be harmful to organisms and plants that live in these water bodies. The sources of the pollutants can be considered as organic and inorganic:

 

a)  Organic

§             Insecticides and herbicides, a huge range of organohalides and other chemical compounds

§             Bacteria from sewage or livestock operations

§             Food processing waste, which can oxygen-demanding substances, fats and grease

§             Tree and brush debris from logging operations

§             VOCs (volatile organic compounds), such as industrial solvents, from improper storage

§             DNAPLs (dense non-aqueous phase liquids), such as chlorinated solvents, which may fall at the bottom of reservoirs, since they don't mix well with water and are denser

§             Petroleum hydrocarbons, including fuels (gasoline, diesel fuel, jet fuels, and fuel oil) and lubricants (motor oil). (Note: VOCs include gasoline-range hydrocarbons.)

§             Detergents

§             Various chemical compounds found in personal hygiene and cosmetic products

§             Disinfection by-products found in chemically disinfected drinking water

b)  Inorganic

§             Ammonia from food processing waste

§             Heavy metals including acid mine drainage

§             Acidity caused by industrial discharges (especially sulfur dioxide from power plants)

§             Pre-production industrial raw resin pellets, an industrial pollutant

§             Chemical waste as industrial by-products

§             Fertilizers, in runoff from agriculture including nitrates and phosphates

§             Silt (sediment) in surface runoff from construction sites, logging, slash and burn practices or land clearing sites

Besides, large visible items such as trash items (e.g. paper, plastic, or food waste) discarded by people, nurdles and shipwrecks, also causes water pollution. Actually, water pollution is a serious problem and can cause a number of impacts to the earth. There are a few examples of the impacts:

§             Waterborne diseases

Which are caused by protozoa, viruses, bacteria, and intestinal parasites and are directly transmitted when contaminated drinking water is consumed. Contaminated drinking water, used in the preparation of food, can be the source of foodborne disease through consumption of the same microorganisms. According to the World Health Organization, diarrheal disease accounts for an estimated 4.1% of the total DALY global burden of disease and is responsible for the deaths of 1.8 million people every year. It was estimated that 88% of that burden is attributable to unsafe water supply, sanitation and hygiene, and is mostly concentrated in children in developing countries.

§             Impact of marine debris

Many animals that live on or in the sea consume flotsam by mistake, as it often looks similar to their natural prey. Plastic debris, when bulky or tangled, is difficult to pass, and may become permanently lodged in the digestive tracts of these animals, blocking the passage of food and causing death through starvation or infection. Tiny floating particles also resemble zooplankton, which can lead filter feeders to consume them and cause them to enter the ocean food chain.

Toxic additives used in the manufacture of plastic materials can leach out into their surroundings when exposed to water. Waterborne hydrophobic pollutants collect and magnify on the surface of plastic debris, thus making plastic far more deadly in the ocean than it would be on land. Hydrophobic contaminants are also known to bioaccumulate in fatty tissues, biomagnifying up the food chain and putting great pressure on apex predators. Some plastic additives are known to disrupt the endocrine system when consumed; others can suppress the immune system or decrease reproductive rates.

Some organisms have adapted to live on mobile plastic debris, which has allowed the inhabitants to disperse all over the world and become invasive species in remote ecosystems.