Researchers at the Institute of Ecology at the Higher School of Economics, together with other Russian researchers, have discovered that drinking water in lakes in the Murmansk region is contaminated. The most prevalent contaminants were found to be nickel and copper. Furthermore, water treatment systems in the region do not remove toxic metals. Heavy metals that accumulate in the water also include cadmium and lead. All four elements were detected in the kidneys and livers of the inhabitants of Monchegorsk.
http://iopscience.iop.org/article/10.1088/1748-9326/aab5d2The study was conducted in industrially-developed cities (Monchegorsk, Apatity, Olenegorsk) and in more remote settlements (Alakurtti and Lovozero), where drinking water is taken from surface water sources. The results of the study have been published in Environmental Research Letters.
Scientists used fish as a bioindicator of water pollution, since fish and human organisms accumulate heavy metals in a similar way. The authors of the study measured the content of heavy metals in the liver and kidneys of fish.The researchers also analyzed tissue samples of 110 deceased patients, aged 35-60, who spent at least 10 years in the areas where the study was conducted, had never worked in factories or other locations posing high risks to their health, and did not suffer from chronic alcoholism or viral hepatitis. It was discovered that in 24 out of 110 observed cases, the diseases were not diagnosed while the patient was alive.
Based on the results of histological, clinical and postmortem examination of patients in the liver and kidneys, a high content of toxic metals, especially cadmium, was found. 'It is a well-known fact that exposure to highly toxic compounds can destroy the endocrine system, increase the frequency of congenital malformations and alter the hormonal environment of the parents.
Studies conducted in various populations living in the Russian Arctic have shown that low air temperatures can significantly intensify (up to five times) the harmful effects on the human body caused by exposure to toxic substances, even at concentrations which do not exceed the permissible limits.
It seems obvious that the permissible concentrations of harmful substances should not be the same in both subtropical Sochi and Arctic Norilsk, simply because of the massive differences in the processes of degradation and assimilation of these contaminants. However- they are indeed the same.
Damage to the economy and other consequences of the contamination have not been fully evaluated, but there are scientifically confirmed facts. For example, in indigenous populations living in the Arctic, there has been a sharp change in the ratio of sexes of newborns (up to 2.5 times more girls than boys are born), and there are other disturbing statistics,' says Boris Morgunov, one of the authors of the study and Director of the Institute of Ecology at the Higher School of Economics.
What kind of water do people in the Murmansk region drink?
The main elements polluting the water in the Kola region are nickel and chromium, due to the activity of large copper-nickel plants. Scientists detected high levels of contamination within a radius of 30 km of the smelters. They also detected background levels of metals at a distance of up to 100 km due to smoke emissions, including dust particles and sulfur dioxide. The results of the study showed that the toxic metals are not removed from the treated water. Concentrations of certain metals, especially iron and manganese, are higher in the water pipes.
Scientists also discovered that chromium, nickel and cadmium accumulate most in the livers of fish and in the kidneys, nickel and cadmium. The levels of these harmful elements in fish organs are much lower (especially nickel) in lakes located far from cities (near the villages of Lovozero and Alakurtti). However, in spite of the distance from industrial centers, the cadmium content in the kidneys of fish is extremely high. It was measured at 1.9 g and 5.1 g of dry mass (excluding fish taken from Lake Lovozero).In areas of the Kola Peninsula which are contaminated by nickel-cobalt smelting, the most serious diseases (nephrocalcinosis and fibroelastosis) were detected in the kidneys of fish. In comparison to the lake water, the concentration of iron in water in the pipelines in Monchegorsk is more than three times higher, and in Apatity - more than five times. The concentrations of many elements in the water taken from the aqueduct were no lower than in the lake water, which indicates a poor water purification system.
How harmful metals in water affect human health
The accumulation of copper in liver tissue taken from residents of the areas in the study was significantly higher (significance level of p <0.05) than in the control group. The concentration of heavy metals in liver samples taken post mortem from residents of Monchegorsk was 2 times higher than normal for nickel, copper, cobalt, cadmium and lead. The concentration of cadmium found in the kidney tissue was more than 5 times higher than in the control group. Scientists have confirmed the hypothesis that the accumulation of copper and cadmium in the liver and kidneys was found to be normal for the inhabitants of Apatity, as were the concentrations of nickel, copper, cobalt and cadmium in samples taken from the inhabitants of Olenegorsk. The accumulation of copper was also found to be normal for the inhabitants of the villages of Lovozero and Alakurtti.
The highest rates of morbidity were measured in the populations of cities that consume water from the lakes of Imandra (Apatity and Monchegorsk) and Moncheozero (Monchegorsk), where the highest concentrations of metals were recorded in drinking water.
The greatest threat posed by the contamination relates to the growth of malignant neoplasms. According to the statistics, the number of reported cases of tumors averaged 13.0 per 1000 in Monchegorsk, 18.1 per 1000 in Apatity and 10.4 per 1000 in Olenegorsk.
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Journal
Environmental Research Letters