humans and to the environment is a matter of great concern. We took indoor dusts and other dusts caused during the process of waste recycling as research targets, and studied characterization of their physico-chemical properties, transport models, and exposure impacts.

Brominated flame retardants (BFRs) such as polybrominated diphenyl ethers in indoor environments were investigated by toxicological and physicochemical approaches. Bromine is transferred from products to dust matrixes not only through miniaturization and subsequent direct migration into dust as plastic and textile fragments but also through other pathways such as vaporization and airborne transfer of micro particulates. Chemical analysis was combined with the DR-CALUX assay and HPLC fractionation to quantitatively evaluate dioxin-like compounds in indoor dusts. Median-based contributions of the theoretical CALUX-TEQs calculated for PBDFs, PCDDs, PCDFs, non-ortho Co-PCBs, PCNs, and mono-ortho Co-PCBs to the experimental values were 17%, 14%, 8.8%, 0.98%, 0.10%, and 0.019%, respectively, which indicates that PBDFs, which are not internationally regulated dioxins, were important dioxin-like compounds in indoor dust.

To evaluate the effects of residual chemical substances of indoor environment, especially BFRs, on respiratory and immune systems, we investigated whether BFRs affect the splenocytes, bone marrow-derived dendritic cells (BMDC) and bronchial epithelial cells in vitro. The present results suggest that BFRs can aggravate immune/allergic reactions through the activation of immune cells including the increase of CD86 expression and IL-4 production in splenocytes, enhance the differentiation and activation of BMDC, and can induce and/or aggravate respiratory inflammation through the enhanced production of proinflammatory cytokines and EGF from the bronchial epithelial cells.

In local survey, electronic waste recycling sites in Bangalore, India, and Dong Mai, Vietnam were intensively studied. In global survey, hepatic Hg level in cetaceans, which have been archived in Environmental Specimen Bank, Ehime University, Japan since 1970s, were used to assess the temporal change in Hg level in open ocean. The results of both surveys suggested significant environmental and biological impacts of heavy metals derived from Asian countries.

As a result of home visiting survey, the numbers of HHW storage were between 97 and 229 per household. We found that some home keeping products have leaked their content which was considered risks of long-term keeping. As a result of collection trial of broad hazardous and dangerous waste containing household hazardous waste in Kyoto city at 7 sites for three times each, 1,113 participants and 9,253 kg of wastes were obtained, and also the knowledge for domestic use and dead storage for each item was acquired. Moreover, although it turned out that citizens' needs for such collection are clear, detailed discussion is required especially for material flow and stock amounts estimation, recycling and/or treatment methods for each items, and responsibility or partnership of producers, detailers, consumer, governments and recyclers.

Key words: 3R (Reduce, Reuse and Recycle), Waste Management, Policy Developments, dioxin-like compounds, DR-CALUX, indoor dust, PBDFs, Brominated flame retardants (BFR), Indoor Environment, Allergy, in vitro bioassay, Heavy metals, Asian developing countries, Electronic waste recycling sites, Household Hazardous Waste, Dead storage, Collection system