Through experimental simulation and field observation, the mechanisms for photochemical transformations of PAHs and PBDEs in fine particles in the atmosphere were studied, and the regional magnitude and mechanism for long-distance migration of POPs in low latitude regions were explored. On this basis, a multi-media regional model for PAHs in the Pearl River Delta region was studied, and tested with field observation results. By use of the interdisciplinary means based on both organic geochemistry and environmental science, typical towns and cities with high exposure to pollution of POPs resulted from extensive treatment of electronic wastes were treated as target areas, and the size, composition of fine particles, as well as composition, distribution, concentration and exposure level of major POPs, in the atmosphere in high exposure environment were studied. Molecular markers and compound-specific isotope technology were used to set up a spectrum for the composition of pollution source of electronic wastes, then pollution source analysis and tracking were performed. Also, occurrence, distribution, activation of POPs in the water/sediment profile and their ecological effect were studied, and the origin and evolution of high risk zones/hidden high risk zones of POPs were explored. Based on distribution of POPs in the environment, typical POPs (precursors for PCBs-BaP, PBDEs-PCBs and PCDDs-PBDEs and their metabolic active products) and environmental compound samples polluted by POPs in low latitude regions were used as target test samples, for study of the molecular and cell biological mechanisms for damage to organisms (with emphasis on mutagenicity) posed by individual or joint effect of POPs (with emphasis on the synergistic effect). Population with high exposure of POPs, i.e., population of residents around places for disposal or stockpiling of electronic wastes, was selected as major subject of the study, and the exposure features, internal exposure level and early stage effect on health of population exposed to PCBs, PBDEs and PAHs were studied.