The researches of low-level exposures and complex ecotoxicoloical effects are the hotspots of current international environmental and health researches. In the past several decades, there was a sharp worldwide decrease in the category and quantity of amphibians. One important field of ecological researches is to find out the cause of this decrease. And the key to investigate the above issue is to develop model animals and corresponding biological marker technology. Sustained by the “National 863 Project”, original results are obtained in the screening of environmental endocrine disruptors, and the aspect of two model animals including Gobiocypris rarus and Xenopus laveis.

Many researches show that the environmental pollution of toxic chemical pollutants is the important factor influencing the propagation of biotic population. In the initial research, Xenopus laveis is used for the research of toxicological effects to develop the experimental methods of long-term and short-term exposure. During the development of the model of Xenopus laveis, PCBs are found to influence the development of gonad for Xenopus laveis, and the research also shows that the exposure of PCBs leads to the deformation of front legs for 80% Xenopus laveis, and the fine structural researches found that the deformation is caused by the wrong connection between the humerus joint and shoulder joint. The sort of deformation has never been reported in other animals, which may be a good clue to investigate the development of bones for vertebrates. The experimental data of the influences of PCBs on the hypothyroid of Xenopus laveis are first obtained in the world. The above research results laid a foundation on the on-site research of ecotoxicology for vertebrates. The work is published in the influential journal “Environ. Health Perspective” in the environmental and hygienic field.

The experiment of low-TBT chronic exposure for Gobiocypris rarus shows the fish cheek cell and liver cell are sensitive to pollutants, both of the Hepatosomatic Index (HSI) and Gonad Somatic Index (GSI) changed obviously. Simultaneously, chemical analysis shows that the fish has a high enrichment ability for TBT. The work about Gobiocypris rarus is appraised as “it may be possibly developed into experimental fish in China and Asian regions”. Vitellogenin is the most main bimarker used for the screening in vivo of environmental endocrine disruptors, and the laboratory has developed new two-step chromatography to determine vitellogenin, and in combination with the developed ELISA method, the feminization phenomenon of fishes caused by Environmental Endocrine Disruptors in Haihe region, Tianjin, China was evaluated, and it is found that 100% of the sea catfish has appeared feminization phenomenon.

In the research of environmental endocrine disruptors in the region around Bohai Sea, the laboratory has worked in the area for ten years or so, and accumulated a large amount of scientific data. It is found that “hermaphroditism” phenomenon occurs in Ropana venosa, which is caused by organotin pollution. Based on many data and sample analysis, new bimarker for soft body Benthos is founded - Mya arenaria Linnaeus. The enrichment mechanism of Mya arenaria Linnaeus is explained from the molecular and cell level, and this work is published in the column of New Initiative of the journal of Environ. Pollut.