Wad does water pollution means?

Question

be more specific if can...thx. =P

Answer 1

From Wikipedia:

Water pollution is a large set of adverse effects upon water bodies such as lakes, rivers, oceans, and groundwater caused by human activities. Although natural phenomena such as volcanoes, storms, earthquakes, etc. also cause major changes in water quality and the ecological status of water, these are not deemed to be pollution. Water pollution has many causes and characteristics. Increases in nutrient loading may lead to eutrophication. Organic wastes such as sewage impose high oxygen demands on the receiving water leading to oxygen depletion with potentially severe impacts on the whole eco-system. Industries discharge a variety of pollutants in their wastewater including heavy metals, organic toxins, oils, nutrients, and solids. Discharges can also have thermal effects, especially those from power stations, and these too reduce the available oxygen. Silt-bearing runoff from many activities including construction sites, deforestation and agriculture can inhibit the penetration of sunlight through the water column, restricting photosynthesis and causing blanketing of the lake or river bed, in turn damaging ecological systems. Pollutants in water include a wide spectrum of chemicals, pathogens, and physical chemistry or sensory changes. Many of the chemical substances are toxic. Pathogens can obviously produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry include acidity, conductivity, temperature, and eutrophication. Eutrophication is the fertilisation of surface water by nutrients that were previously scarce. Even many of the municipal water supplies in developed countries can present health risks.

Water pollution is a major problem in the global context. It has been suggested that it is the leading worldwide cause of deaths and diseases[1][2], and that it accounts for the deaths of more than 14,000 people daily[2].

Answer 2

It means that the water has been contaminated with impurities. For example if water contains high levels of pesticide it would be very harmful for you to drink or use for cooking.

Other examples of pollution in water would be chemicals , fertilizers from farming, and untreated sewage. Again the water wouldn't be safe to drink or use. Fish would make you sick if you ate it, plus over time wildlife would start dying such as marine animal, fish, and birds.

Lastly polluted water in a lake or ocean would make you sick if you swam in it. Oceans can be polluted from industry waste (chemicals), oil spills, toxic wastes being dumped , high levels of fertilizers from farming and untreated sewage.