Exposure, Intake and Effects of Toxic and Essential Elements

The Ministry of Science, Education and Sports of the Republic of Croatia (2002-2006)

Principal investigator: Maja Blanuša

In the forthcoming period factors influencing an increase in toxic metal concentrations in the body at an early age will be studied on suckling rats. Special attention will be given to some dietary components like calcium, selenium, and vitamin C. New data on the interaction of essential dietary components with toxic metals (lead, cadmium, mercury) will be obtained. The efficiency of chelation therapy at an early age, especially during ongoing exposure to toxic metals, is investigated as a contribution to treatment of metal poisoning in children. The following chelating agents are used: meso-2,3-dimercaptosuccinic acid (DMSA), sodium-(RS)-2,3-dimercapto-1-propanesulfonate (DMPS) and calcium-trisodium-diethylenetriaminepentaacetate (DTPA). Dietary supplementation and/or chelation therapy are administered during or after exposure to lead or cadmium to obtain highest reduction in tissue concentrations of these toxic metals. The health effect of such treatments and tissue essential element concentrations will be also evaluated. The efficiency of combined chelation therapy with DMSA and DTPA will be evaluated in older rats for treatment of acute cadmium poisoning. The influence of selenium on the efficiency of chelating agents, DMSA and DMPS for reducing tissue mercury concentrations will be also studied. The effect of cigarette smoking on concentrations of metals and steroid hormones is evaluating in human placental tissues. For monitoring purposes the ratio of heavy metals in soil, plants (mushrooms), and isopods is measured. The importance of calcium intake during the suckling period for bone mineral contents in adult age is assessed in an animal model. In epidemiological studies the effects of environmental and nutritional factors as compared to genetic factors on bone mineral content will be estimated in children and adults.