Evaluation of the skin uptake of mercuric chloride in man

Skin on the forearms of male human volunteers was exposed to aqueous HgCl2 solutions. It was assumed that loss of mercury from the test solution was equivalent to percutaneous absorption. Two parameters important for influencing uptake considered as the rate of absorption were investigated: the concentration of HgCl2 solutions (0.01, 0.1 and 0.2 M) and the time of exposure (5, 10, 15, 30 and 60 min). The absorption rate from 0.1 M HgCl2 solution decreased from 9.3 micrograms cm-2 min-1 during a 5 min exposure to 2.5 micrograms cm-2 min-1 during a 1 h exposure. A ten-fold decrease of HgCl2 concentration resulted in an approximately ten-fold decrease of the absorption rate, from 4.6 to 0.4 microgram cm-2 min-1 during a 30 min exposure. The results indicate that the absorption rate is a directly related function of concentration and an indirectly related function of time of exposure.