Heavy metals include cadmium, lead and mercury. All of them in excess quantities can cause irreversible changes in the human body. Heavy metals are no less dangerous for the environment.
The harm of heavy metals to humans
Areas in which there is an excessive concentration of heavy metals are located near factories where waste is incinerated or highly concentrated substances (paints, varnishes, etc.) are processed. Lead in the form of dust is on the soil and plants, with the help of which it enters the human body. A high concentration of heavy metals is extremely dangerous for children, as it greatly slows down their mental and physical development.
Lead is not excreted from the body. It tends to accumulate, as a result of which chronic diseases are exacerbated. Brain damage often occurs, resulting in mental retardation, aggressiveness, and hallucinations. Children are especially susceptible to this. Lead several times enhances the effect of any carcinogen that has entered the body. In some cases, a cancerous tumor may appear.
Excessive amounts of cadmium and mercury (especially its organometallic compounds) can cause cancer. Mercury poisoning is accompanied by a sudden change in mood and tremors in the hands. High concentrations of cadmium dust in the air can cause breathing difficulties due to respiratory tract damage.
In the 20s of the last century, a plant was built in the United States to enrich gasoline with tetraethyl lead, a very poisonous compound. The level of lead in the body of all residents of the country for another 50 years was several times higher than the norm. Today, developed countries have abandoned such harmful production for humans. The primary processing of non-ferrous metal ores was also prohibited.
The harm of heavy metals to the environment
Heavy metals are one of the natural constituents of the lithosphere. Their concentration in the earth's crust and soil is very low, but due to various waste emissions and factories, it can increase dramatically. In this case, all living organisms will suffer. The biological balance of an area where there is a high concentration of toxic metals is severely disturbed. Irreversible changes take place in the body of animals.
If a person eats their meat, he can also be poisoned. There are cases when, when eating fish with an excessive content of cadmium, itai-itai disease developed. It is accompanied by intolerable pain in the spine and lower back. With the wrong treatment, everything ends in death.