Study Group for POPs and Related Chemicals he present research group attempts to elucidate regional and global pollution and accumulation features of biota in the marine and terrestrial environment by Persistent Organic Pollutants (POPs) and related compounds such as HCH (hexachlorocyclohexane), PBDEs (polybrominated diphenyl ethers), and organotin compounds. At the same time, this group takes significant role in suggesting scientific measures to the government and public on the protection of the environment against such chemical risks. Our major study subjects are to make clear 1) global pollution of air and water, 2) status of pollution and its source in developing countries, 3) bioaccumulation mechanisms of biota in marine and terrestrial ecosystems, 4) status of pollution and its risk assessment for humans, 5) temporal trend and future prediction of marine pollution. Our recent distinct studies accredited by world scientists are our findings like 1) pollution of PBDEs has globally spread in the marine environment, 2) pollution sources of PBDEs might also be present in Asian developing countries, 3) dioxins and related compounds have been formed in the open dumping sites of municipal wastes in Asian developing countries, and 4) dioxin pollution are highly extensive in the northern hemisphere. Study Group for Trace Elements his group focuses on the Environmental Chemistry and Ecotoxicology of trace elements, including toxic (e.g. mercury and cadmium) and essential elements (e.g. zinc and copper). The group also concentrates on some of the trace elements of recent interest, such as gallium and antimony, which may be expected to increase in the environment in recent future because of their widespread use in electronic industries. Two major research themes dealt with the team are 1. Contamination status and risk assessment of trace elements on wildlife and human in developing Asian countries 2. Accumulation feature and detoxification mechanism of trace elements in wildlife.

Voyage to the Arctic to understand the status of contamination Dioxin pollution from open burning of wastes -a common sight in the dumpsites of Asia Mortality by distemper virus in seal -suspected effect of chemical contaminants Deformed beak in cormorant -consequence of environmental pollution

Study Group for Ecotoxicology 1. Molecular characterization of cytochrome P450 as a biomarker of contamination and effects of environmental chemicals Expression of certain cytochrome P450 (CYP) subfamilies is inducible by environmental contaminants, and the induced CYP is of toxicological significance because the CYP induction is occasionally involved in the disruption of the signaling pathways regulated by endogenous substrates, biotransformation of contaminants to harmful intermediates and the production of reactive oxygen species. Therefore, the CYP expression level and the enzymatic activity can be used as biomarkers of exposure to environmental contaminants and their effects in wildlife. We investigate the relationship between residue levels of environmental contaminants and expression levels of CYPs in wild species populations. To evaluate the metabolic potentials of environmental and endogenous compounds in wild species, we also characterize the catalytic functions of individual CYP isozymes from each species. 2. Monitoring chemically-induced disruption of intracellular signaling pathway networks It is well known that organisms respond to chemical exposure by altering the profile of gene/protein expression. This indicates that if we could monitor the disruption of intracellular signaling pathway networks that is chemically induced in organisms, effects on physiological functions that the networks govern may be assessed. We therefore attempt to establish the monitoring systems of genes/protein profiles by applying the principles of toxico-genomics and –proteomics for risk assessment of wild species. 3. Understanding molecular mechanisms underlying species-specific toxicity and susceptibility The toxic effects and susceptibility to chemicals are greatly different among species. As a factor to explain the species differences, the differences in genes coding nuclear receptors and xenobiotic metabolizing enzymes are postulated. Comparative studies in key species representing phylogenetically or ecotoxicologically relevant groups will lead to more fundamental understanding of gene products related to diversity of toxicities and sensitivity to chemicals. Therefore, we attempt to analyze function of genes coding nuclear receptors and xenobiotic metabolizing enzymes in wildlife. Go to top this page.