Genotoxicity and bioaccumulation of methyl mercury and mercuric chloride in vivo in the newt Pleurodeles waltl.

Larvae and embryos of the urodele amphibian Pleurodeles waltl were raised for several days in water containing low concentrations of methyl mercuric chloride (CH3HgCl) or mercuric chloride (HgCl2). Examination of squash preparations from treated embryos showed that both compounds induced chromosome breaks and c-mitosis. Examination of blood smears from the larvae demonstrated a higher level of micronucleated erythrocytes in the animals raised in the mercury-containing water than in controls raised in uncontaminated water. The bioaccumulation of both compounds was evaluated by determination of mercury levels in the larvae. After 12 days of treatment, concentration factors (concentration in the organism/concentration in the water) of approximately 1200 and approximately 600 were found for methyl mercury and mercuric chloride, respectively.