The aims of the present project were to (1) investigate distribution of 7 groups and 50 concerned chemicals in 15 rivers around Taiwan, (2) update the analytical data and link to assigned database (3) apply multiple chemical management decision-making model tools and provide management suggestions. First, sediment and fish samples were collected from 15 rivers around Taiwanincluding Nankan River, Toucian River, Keya River, Jhonggang River, Houlong River, Da-an River, Wu River, Beigang River, Puzih River, Yanshuei River, Erren River, Dian Bao River, Donggang River, Lanyang River and Shincheng River. Concentrations of dechlorane plus (DP), methoxychlor, perfluorinated alkyl substances (PFASs), pesticides and their metabolites (including glyphosate, aminomethylphosphonic acid (AMPA) and chlorpyrifos, pendimethalin), short-chain chlorinated paraffins (SCCPs), nonylphenol (NP), bisphenol A (BPA), phthalate esters (PAEs), polybrominated diphenyl ethers (PBDEs), hexabrominated biphenyls (HBB), polycyclic aromatic hydrocarbons (PAHs), and metals were measured in collected samples. In total, 17,264 analyzed data were obtained. The analyzed concentrations of certain chemicals in sediments showed decreasing trend. It indicates that the control strategies for these chemicals are effective to reduce their releasing into the environment. However, the concentrations of specific chemicals such as PFASs, SCCPs, NP, BPA, PAEs, PBDEs and HBB in certain river sediments and fishs were higher than those in the previous survey. The findings may be related with the living habit and size (length/weight) of fish or due to decreased contaminated levels of river environment and long-term accumulation of these chemicals by fish. We recommened that it was necessary to continuously monitoring their distribution trend. In the future, candidate chemicals with global concerns, high production volume, environmental hazards and human health effects could be further included for long-term investigation. Second, the analytical data and popular science information were updated to the "environmental distribution survey of chemical substances Information Website". Translation of the website to English and linking the environmental distribution survey data to the Central Data Exchange (CDX System) of the Ministry of Environment were completed. Third, application of multiple chemical management decision-making model tools via pivot analysis, sankey diagram, and fingerprints of the river survey determined , the distribution and correlation of specific pollutants at specific time points and specific media Meanwhile, Toxicological Priority Index (ToxPi) combined the diverse toxicological information integration tool was used to identify and rank the priority of chemicals and sampling sites in nine river basins in the northern Taiwan. The results showed that pesticides, PAHs, PBDEs and PAEs have high ToxPi scores by different data sets. Besides, downstream sampling sites of rivers may need to be paid attention in future sampling strategy, especially in Nankan River. The relevant information is also presented on the geographical information visualization interface using the chemical analysis results and the data from the Pollutant Release and Transfer Register for further decision-making reference.

Chemical substances, Environmental distribution, River, Sediment, Fish, Management Decision Model Tool