Toxicity of Heavy Metals to Mongoloniscus sinensis (Dollfus, 1901) (Crustacea: Isopoda: Oniscidea).

The bioaccumulation of and resistance to different heavy metals in soil was tested using Mongoloniscus sinensis, a terrestrial isopod endemic to china, and results show that: (1) the median lethal concentration (LC50) of Pb, Zn, Cd in the filter paper contact test after 48 h was 197.6, 503.7, 448.0 µg cm- 2, LC50 of Pb-Zn compounds was 173.8 and 440.8 µg cm- 2 and after 14 days of soil contamination LC50 was 2917.0, 2977.9, 5048.4 mg kg- 1, LC50 of Pb-Zn compounds was 1219 and 1463 mg kg- 1. Thus Zn turned out to be less toxic than Cd in the filter paper contact test, while their sequence of toxicity was reversed during the soil exposure test, which shows that M. sinensis can tolerate a dose of Zn and Cd. (2) analysis of body burdens showed that the sequence of internalized metal concentrations was Pb < Cd < Zn, which indicates that heavy metals in soil can be enriched and absorbed by M. sinensis, and that it is much more efficient at absorbing Zn and Cd than Pb.