Combined effect of low dose levels of lead and zinc on bone tissue of rats

Pollution of the environment remains a pressing problem of the global level. The greatest concern is caused by heavy metals, especially lead, which to the greatest extent - up to 90–95 % accumulates in bone tissue of the human body. Aim. The establishment of the bioeffect type of low-dose lead and zinc combined action on bone tissue density by the calcium content in it in the experiment. Materials and methods. For experimental studies Wistar rats were divided into 5 groups. To determine the type of lead and zinc effect on the calcium level in femur bone tissue the content of the latter by the titration method was identified. To evaluate the relationship between low doses of zinc and lead, the combined action coefficient and change of combined action effect coefficient were determined. Results. The analysis of the results shows that the type of lead and zinc low concentrations combined action in their influence on bone tissue density by calcium content in it is characterized as an antagonistic, since the combined action coefficient value was 0.32–0.39. The effect of subacute combined action in binary systems "lead acetate – zinc chloride" and "lead acetate – zinc citrate" is weakened by 2.6 and 3.1 times, respectively. Conclusions. The type of lead and zinc low concentrations combined action provided that they affect the bone tissue density of rats by calcium content in it, which do not exceed the threshold of general toxicity, is characterized as antagonistic, since the combined action coefficient = 0.32–0.39. The effect of subacute combined action in binary systems, "lead acetate – zinc chloride" and "lead acetate – zinc citrate" is reduced by 2.6 and 3.1 times, respectively, compared with their isolated effects, indicating active inhibition of bone tissue lead accumulation by zinc compounds, which is especially characteristic of zinc citrate