For hundreds of millions of people around the worldwater is the main source of fresh water. For example, in many regions of Asia and South America they are used for irrigation of crops - arid conditions do not allow rains to reach these areas. The rest often use groundwater as an alternative source of drinking water, believing that it is healthier. However, scientists have found that in some countries the use of such water can be dangerous due to the high concentration of such a dangerous substance as arsenic. Moreover, they can be poisoned not only while drinking this water, but also when drinking, for example, rice, which is watered with it.
Thanks to several years of research, scientists fromThe Swiss Federal Institute for Aquatic Sciences and Technology has developed a map of the distribution of arsenic in groundwater around the world. They conducted about 200 thousand water analyzes in China, Mexico, South and Southeast Asia, the United States and some other countries. Until now, it was impossible to accurately establish the risk of arsenic poisoning in the use of spring waters, since this required a study of the use of water resources in different regions and the characteristics of agriculture in a particular country.
Ground water represent a layer of fluid in loose rocksland. They are formed due to seepage into the earth of precipitation, as well as the waters of rivers, lakes, reservoirs and other water bodies. Often they come to the surface in the form of springs.
At the same time, groundwater should not be confused with artesian springs. Artesian water is located much deeper underground and is characterized by the presence of strong pressure.
Is it possible to drink water from a spring?
According to World Health Organization (WHO) regulations, permissible concentration of arsenic in drinking water is no more than 10 milligrams per 1 liter. However, scientists have identified several places on Earth,where it is higher (more than 50 milligrams per liter), mainly in South Asia. Foci of arsenic in water have also been found in the United States and Argentina.
Because purely physically impossible to measurethe content of hazardous substances in groundwater in every place on the planet, researchers using mathematical modeling have compiled a map to determine previously unknown areas of arsenic pollution. The most dangerous picture is still observed in Asia and South America. Residents of Europe and Russia and participants in our Telegram chat can not worry - in their groundwater, most likely, the concentration of arsenic is not so high as to cause any health problems. Nevertheless, if we talk about Russia, the map shows that in the groundwater in the western part of the country arsenic is noticeably less (no more than 0.2 milligrams per liter), while closer to Asia it can purely reach 0.6 .
Consistent final risk assessment, threat of exposureArsenic in the body affects up to 220 million people worldwide. This causes some concern, since in Asia, for example, groundwater is widely used to organize water supply. And thanks to the springs, local residents collect drinking water from them.
What is arsenic dangerous
What is dangerous when arsenic enters the humanthe body? Firstly, it is a very toxic chemical element. There are cases when even in dentistry doctors incorrectly calculated the necessary concentration of this substance for the patient (not taking into account chronic diseases and allergic reactions), and as a result a person died. In a small amount, arsenic leads to diseases of the skin and nervous system, but if its concentration is higher, arsenic can lead to diseases of the cardiovascular system and the rapid development of cancer.
However, there are exceptions among living things. For example, last year, scientists in the Pacific discovered a microbe that lives by inhaling and exhaling arsenic. This form of life was almost forced to breathe poison - there is very little oxygen under water, so adaptation has become the only way to survive. In addition to arsenic, microorganisms can breathe sulfur and nitrogen - researchers will have to conduct laboratory experiments to more carefully study the processes inside them.
And due to the mutant gene AS3MT residentsSan Antonio de los Cobres in Argentina is able to drink water whose arsenic level is 80 times higher than safe. The gene allows the body to process arsenic, not allowing it to accumulate in dangerous concentrations, so the owners of these microscopic mutants can eat as much arsenic as they like. However, only 6,000 people in the world have such “immunity”.
How was arsenic found in the ground?waters of the earth? It is found in iron-containing minerals near aquifers and due to chemical processes it is gradually released and enters the water. This process is not quick, and it is unlikely that even after 100 years the concentration of arsenic will become dangerous throughout the world, but now this element can provoke the growth of dangerous diseases in the Asian region, where they not only drink mainly groundwater, but also prepare it with its help. food and cultivated crops.