Toxicity of cadmium sulphate and methylmercuric chloride applied singly or in combination to early mouse embryos in vitro.
The joint action of cadmium and methylmercury was studied at pre-implantation and early post-implantation stages of mouse embryos in vitro. Embryos were exposed to the heavy metals from the two-cell to the blastocyst stage. Toxicity was monitored using developmental (formation of blastocysts, hatching of blastocysts, trophoblast outgrowth, formation of inner cell mass), proliferative (cell numbers) and cytogenetic (micronucleus formation) endpoints. Under some conditions (e.g. 1 mum-CdSO(4) + 0.6 mum-CH(3)HgCl), a combination risk was observed that significantly exceeded the risk expected from the addition of the single effects. This increase in risk, however, was due to the shape of the dose-response curves; that is, cadmium and mercury behaved as if they were the same substance.
Müller
W U
WU
Institut für Medizinische Strahlenbiologie, Universitätsklinikum Essen, D-4300 Essen 1, Federal Republic of Germany.
Streffer
C
C
Joos
A L
AL