| The Yangtze River and the Jialing River are used as the sources of potable water, industry supply and irrigation supply in Chongqing, their contamination status would influence human health directly. As an urbanized and industrialized city at the upstream of the Three Gorges Region Area, the contamination of municipality of Chongqing would influence the water quality of the Region Area. Organic compounds are ubiquitous contaminates in water environment. Although their levels were low in water environment, the organic contaminates exhibit potential risks for environmental safety and human health because of their toxicity and bioaccumulation for organism. Phthalate acid esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) are typical organic contaminants in the water column in Chongqing, which exhibit carcinogenic, mutagenic activity, acute toxicity and have been confirmed as Environmental Endocrine Disruptors (EEDs) and Persistent Organic Pollutants (POPs). A few articles reported the levels of PAEs and PAHs in this region of the Yangtze River, but few articles described their environment behaviors such as migration. Hence, the present study will focus on the following aspects:1. Investigated the organic pollutants in the Jialing River around Chongqing by liquid-liquid extraction coupled with GC/MS.2. Monitored the PAEs and PAHs in surface water of the Yangtze River and Jialing River around Chongqing for one year. Investigated their levels and compositional patterns, and compared the concentrations with other areas and the tolerance limits.3. Determined PAEs and PAHs in suspended particles (SPM), soil in water-level-fluctuation-zone (WLFZ), sediment and wet deposition were determined, and investigated their migration behaviors including temporal trend, spatial distributions, distributions between various phases. Discussed the influence of environmental parameters and source of PAHs simply.The major conclusions were as follows:1. There were about 20 organic contaminants existence in the surface water of the Jialing River were detected. They were straight-chain alkanes and their derivatives, aromatic compounds with one benzene ring, polycyclic aromatic hydrocarbons, phthalate acid esters and other organic compounds.2. Five PAEs including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP) and dioctyl phthalate (DOP) and eight PAHs including naphthalene (Nap), acenaphthylene (Acy), acenaphthene (Ace), fluorene (Flu), phenanthrene (Phe), anthrancene (An), Pyrene (Py) and fluoranthene (Flut) were detected in the study area. The total concentrations of PAEs and PAHs were n.d.-10.405 ug/L (Mean:1.817±2.052μg/L) and 0.071-7.675μg/L (Mean:1.306±1.176μg/L) respectively. The quality of the surface water in Chongqing was safe for human being now because these levers were below the Tolerance Limit (TLs) in drinking water and surface water except DBP. DBP and DEHP were the predominant PAEs. And for PAHs, the low-molecular-weight PAHs (2-rings and 3-rings PAHs) were dominant in surface water.3. The spatial distributions of PAEs and PAHs in the municipality of Chongqing were kept stable. Similar distribution was observed in some compounds which have the similar properties. The levers of PAEs were higher in wet season, but the temporal trends for PAHs were undulate. PAEs and PAHs in the water column were tended to be more present in suspended particle matter (SPM). The migration of these compounds between SPM, soil in water-level-fluctuating-zone (WLFZ) and sediments were dominated by the organic carbon contents. Atmospheric wet deposition was one of the most important modes of PAEs and PAHs migrated from atmosphere to surface water. Furthermore, the concentrations of most PAHs were concern with dissolved organic carbon (DOC), and a weak interrelation were found between the DEHP and the total suspend solid (TSS). At last, the origin of PAHs pollution of the Yangtze River of Chongqing was both petrogenic and combustion, and it would change in different seasons.
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