Effect of administration sequence of mercuric chloride and sodium selenite on their fates and toxicities in mice.

Interaction of mercury and selenium was examined in mice given mercuric chloride (25 mumol/kg) intravenously with sodium selenite (25 mumol/kg, iv) according to various administration schedules. Body weight of the mice given mercuric chloride or selenite alone did not increase, but the mice given both compounds simultaneously grew as well as control mice. On the other hand, only a 1-hr shift of administration of either compound canceled the mutual detoxifying effect. The most conspicuous changes in tissue distribution of mercury and selenium and in gel filtration patterns of both elements accumulating in tissues of the mice were observed when both compounds were administered simultaneously. These experimental results indicate that the interaction of mercuric mercury with selenite in mice occurred to the greatest extent upon simultaneous administration, supporting the hypothesis that the interaction primarily occurs in the blood stream.