After fully understanding the severity of water pollution and its harm, people may realize the significance of water purifier for human health.
What is water pollution? What are the main sources of water pollution?
When dirty and harmful substances enter clean water, water pollution occurs.
Water pollution sources mainly include:
Industrial waste water discharged without treatment; domestic sewage without treatment; farmland sewage using large amount of chemical fertilizer, pesticide and herbicide; industrial waste and domestic garbage stacked on the river bank; water and soil loss; mine sewage.
What harm will water pollution bring?
The following are the main substances that cause water pollution, their sources and hazards:
(1) Dead organic matter:
Source examples: untreated urban domestic sewage, paper making sewage, agricultural sewage, urban garbage
It consumes dissolved oxygen in water and endangers the survival of fish.
Lead to lack of oxygen in water, resulting in the death of microorganisms that need oxygen. It is these aerobic microorganisms that can decompose organic matter and maintain the self purification capacity of rivers and streams. The consequences of their death are: rivers and streams blacken, stink, toxins build up and harm people and animals.
(2) Organic and inorganic chemicals:
Source examples: chemical industry, pharmaceutical factory discharge, paper making, tannery wastewater, building decoration, dry cleaning industry, chemical lotion, agricultural insecticide, herbicide
Most of the organic chemicals are toxic. When they enter rivers and lakes, they will poison or kill aquatic organisms, causing ecological damage.
Some organic chemicals will accumulate in aquatic organisms, causing poisoning after human consumption.
The water polluted by organic chemicals is difficult to be purified, and the safety and health of human drinking water are threatened.
Source example: large-scale application of phosphorous washing powder and phosphorous nitrogen fertilizer
Causing Algae blooms in the water. Because phosphorus is an important element for the growth of all organisms. In nature, phosphorus is rare. After the phosphorus wastewater discharged by human beings enters into the lake, the algae in the lake will get rich nutrition and increase rapidly (called eutrophication of water).