Occurrences of Green Oyster and Heavy Metals Contaminant Levels in the Sien-San Area, Taiwan

An abnormal increase of copper concentrations was observed in both the oyster tissues and sediments of the Sien-San coastal area in the north-western part of Taiwan. As much as 200 and 5000 ppm of copper was found in sediments and oysters. These excessive concentrations of copper were introduced to the coastal area within a short period of about 4 yr. Copper concentrations increased 50 and 100-fold respectively in oyster tissues and sediments. The green oyster phenomenon occurred as a result of these rapid increases in metal concentrations. The appearance of green oysters and the abnormal concentrations of copper demonstrated that the Sien-San coastal area is undergoing a drastic change as a result of copper pollution. This pollution problem represents a serious threat to the local fishing community.