Every living organism needs macro- and microelements. Macroelements are calcium, magnesium, strontium, barium, iron, aluminum, manganese, potassium, and sodium. Microelements are iodine, selenium, cobalt, molybdenum, boron, zinc, and some other chemical elements. All these mentioned elements participate in any living being’s metabolism – both lack and excess of one or another element may cause diseases of plants and animals.

“Too much is as bad as too little”, says the head of biogeochemistry laboratory of the Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences. The lack of even such toxic elements as nickel, cadmium and lead may cause dysfunctions. That is why some animals eat red toadstools – they contain cadmium. That is why it is incorrect to describe environment according to maximum permissible concentrations of chemical agents – experts need to know which elements are in excessive concentrations, and which elements are in deficiency.

Thus the scientists have developed biogeochemical criteria for estimating ecological conditions of a region – finding maximum and minimum concentrations with which human beings and other region dwellers show signs of poisoning. Natural soil formation processes have divided the surface of our planet into several biogeochemical provinces, which differ in element concentrations. Human activities disturb natural balance of said elements in the environment – some of them accumulate, and others disperse. That is why industrial zones have their own biogeochemical provinces – South Ural and Norilsk, for example, have excessive concentrations of copper, zinc, nickel, cobalt, and lead (poly-metal provinces); Tuva has too much nickel (nickel province); Altai, Caucasus, and Baikal have too much lead (lead provinces), etc.

In order to find element’s concentration, which is essential for life, one should know how actively the element is involved in metabolism. Scientists have developed an ecological and biogeochemical technique for detecting element concentration fluctuations along the whole food chain, thus finding its critical concentration in the environment, diet, and organisms. Regional estimation criteria also include element concentration ratios – for instance, calcium-phosphorus and calcium-strontium ratios are very important for bone formation, and iodine and selenium are essential for the thyroid gland, being part of enzymes, regulating thyroid hormones.

Another selenium-containing enzyme can be found in blood cells – erythrocytes. This enzyme is considered to maintain human immune system and its lack leads to tumor development. Russia has some regions, which lack selenium – their population should take special food additives with selenium or simply eat more mushrooms and garlic, which are natural selenium accumulators. However, before taking any measures, one should know exactly where and what element is in deficiency – thus all data on microelement concentration in soil, water and animals are processed and put on ecological and biogeochemical maps, which also contain information on various diseases caused by microelement deficiency. Such dynamic maps show areas with concentration deviations on various stages – risk, crisis and disaster.

Scientists continue their studies of microelements, which will further help them make necessary correction in their technique and avoid possible diseases of human beings and animals.

Sources:

    www.rfbr.ru
    www.geokhi.ru
 

Anna Kizilova