Metal concentrations in sediments of the Tamsui River, flows through central metropolitan Taipei

This work analyzed metal concentrations and potential sources of sediment pollutants in the Tamsui River, Taiwan, by instrumental neutron activation analysis. The Tamsui River, the second longest of Taiwan's three major rivers, flows through metropolitan Taipei City in northern Taiwan and is renowned for its preserved mangrove wetlands. In total 11 elements Al, As, Br, Cs, Fe, La, Mg. Mn, Na, Sc, and Ti were identified in 24 samples taken from three sites upriver, the mangrove area and estuary during the spring of 2004. Specifically, the most abundant Al metal concentration was 15.6-0.92 mg/g adopted as standard reference in this study. Only few sites had As at the statistical meaning (>DL). Furthermore, arsenic concentrations fluctuated at roughly 0.67 +/- 0.09 mg/kg based on variations in background counts in various gamma-ray spectra. Elemental concentrations of these elements were compared with those in other nations, and discussed in the context of enrichment factors calculated for elements using the earth crust of various sediments as references, based on elemental values of Al.