Water pollution

 How not to endanger our source of life

The planet continually reminds us, with increasingly extreme droughts, that without water there is no life. This resource is essential not only for the survival of the living beings that inhabit it, but also for socioeconomic development, energy production or adaptation to climate change. However, today, we face an enormous challenge: the pollution of rivers, seas, oceans, canals, lakes and reservoirs.

WHAT IS WATER POLLUTION

The World Health Organization (WHO) defines contaminated water as water that undergoes changes in its composition until it becomes unusable. That is, it is toxic water that can neither be drunk nor used for essential activities such as agriculture, as well as a source of unhealthiness that causes more than 500,000 deaths annually globally from diarrhea and transmits diseases such as cholera, dysentery, typhoid fever and polio.

The main contaminants of water include bacteria, viruses, parasites, fertilizers, pesticides, drugs, nitrates, phosphates, plastics, fecal waste and even radioactive substances. These elements do not always stain the water, making water pollution invisible on many occasions. For this reason, chemical analysis of small samples and aquatic organisms is often used to know the state of water quality.

CAUSES OF WATER POLLUTION

Natural factors, such as the leaching of mercury into the Earth's crust, can pollute oceans, rivers, lakes, canals and reservoirs. However, it is usual that the deterioration of water comes from human activities and their consequences, which we detail below.

1° Global warming

The increase in the earth's temperature, due to CO2 emissions, heats the water and this causes its oxygen level to decrease.

2° Deforestation

Clearing forests can deplete water sources and generate organic residues that serve as breeding grounds for polluting bacteria.

3° Industrial, agricultural and livestock activities

Chemical discharges from these sectors are one of the main causes of water eutrophication.

4° Garbage and sewage discharges

The UN says that more than 80% of the world's wastewater that reaches the sea and rivers is untreated.

5° Fuel spills

The transport and storage of oil and its derivatives lead to seeps that can reach water sources.

CONSEQUENCES OF WATER POLLUTION

• Destruction of biodiversity. Water pollution impoverishes aquatic ecosystems and facilitates the uncontrolled proliferation of phytoplanktonic algae in lakes (eutrophication).
• Contamination of the food chain. Fishing in polluted waters, as well as the use of wastewater in livestock and agriculture, can transmit toxins to food that harm our health through their intake.
• Shortage of drinking water. The UN admits that there are still billions of people in the world without access to safe water and sanitation, especially in rural areas.
• Diseases. The WHO estimates that some 2 billion people drink drinking drinking water contaminated by excreta, putting them at risk of diseases such as cholera, hepatitis A and dysentery.
• Infant mortality. According to the UN, diarrhoeal diseases linked to poor hygiene kill about a thousand children a day worldwide.

SOLUTIONS FOR WATER POLLUTION

Reduce CO2 emissions to avoid global warming and ocean acidification.

Mitigate the use of chemical pesticides and nutrients on agricultural crops.

Reduce and purify wastewater safely so that, in addition to not polluting, it can be reused for irrigation and energy production.

Limit the use of single-use plastics that end up floating in rivers, lakes and oceans, many in the form of microplastics.

Promote sustainable fishing to ensure the survival of species and avoid impoverishment of the seas.