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Pollutant concentrations detected in oysters from 12 different culture areas of Taiwan (especially for the Hsiangshan area and the Machu Islands) from 1991/98 were evaluated to investigate potential carcinogenic (inorganic As and organochlorine pesticides) and non-carcinogenic (Cu, Zn, Cd and inorganic As) risk to the public from ingestion ofthe oysters. The highest geometric mean (GM) Cu and Zn concentrations of 1108 (range 113/2806) and 1567 (range 303/3593) mug/g dry weightwere obtained in oysters from the Hsiangshan coastal area. The maximum GM Cd and As concentrations of 6.82 and 19.3 mug/g dry weight werefound in oysters from the Machu Islands area. The p,p'-DDE values range from not detectable in Penghu Islands' oysters to 164 ng/g dry weight in Machu Islands' oysters. The highest tDDT (sum of p,p'-DDE, p,p'-DDD and p,p'-DDT) concentrations of 337 and 340 ng/g dry weight were found in oysters from Kimmen and Machu Islands, respectively. A calculated target hazard quotient (THQ; daily intake/reference dose) of11.4 (based on 139 g oysters/day) for Cu caused by consuming oystersfrom the Hsiangshan area is higher than that from other areas (range0.124/5.95). The highest average Cu intake from Hsiangshan's oystersfor individuals is 11.4 times (i.e. THQ=11.4) more than that of reference dose (40 mug/kg/day). However, the maximum THQ values for Cd and As caused by consuming oysters collected from the Machu Islands were 5.57 and 2.63 for Cd and As, respectively. Generally, the results of THQ showed that if only the maximally exposed individuals were considered, the value of 65.4% for oyster was higher than 1.0 in comparison with reference dose. All cancer risk estimates for inorganic As from consuming oysters were higher than 10-6 (range from 128x 10-6 to 509x 10-6 for maximally exposed individuals and range from 17.1x 10-6 to 68.0x 10-6 for typically exposed individuals, respectively); that is the risk ofthe low [ABSTRACT FROM AUTHOR]

Pig farming is a major industry in southern Taiwan, with two million pigs being raised along the banks of the Kaoping River. Excretions from pigs are discharged into the river and carried into the sea. In this study, 24 surface sediments and 1 sediment core off southwestern Taiwan were analyzed to determine, quantitatively, the extent of coprostanol addition and its distribution, and to obtain the input of coprostanol over the past. Geographically, the percent of coprostanol is highest around the river mouth, and decreases to about 1% at the shelf break and close to 0 at 40 nautical miles from the river mouth. The progressive seaward decline of the percent of coprostanol from the river mouth can be attributed to dilution of coprostanol by uncontaminated sediment and/or sediment containing lower levels of coprostanol, dilution of coprostanol by biogenic sterols, and degradation of coprostanol. Kaoping Canyon sediments contain a high percent of coprostanol, which can be attributed to a direct input of river sediments, canyon currents being alternate up canyon and down canyon, and the blocking effect of a high topographic. [ABSTRACT FROM AUTHOR]