Distribution of heavy metals along the Machu/Taiwan - Minjiang/China estuarine and coastal waters, sediments and bivalves

A long-term Asia/Pacific Mussel Watch program along the Machu/Taiwan and Xiamen/China coastal area has been carried out. Extremely high values of Zn(110 ug/g) and Cu (201 ug/g) with relatively high values of Pb (30.8 ug/g) and Cr (162 ug/g) were found in mud samples (<63 urn) separated from sediments at station MRI (close to Minjiang estuary), the calibration station for the Asia/Pacific Mussel Watch Program between Taiwan and Xiamen Universities, might indicate the sources of pollution. The heavy metal contents of bivalves varied among different marine organisms. The orders of bioaccumulation of heavy metals (dry weight) in bivalves (including barnacles) are as follows: Zn, Mitella mitella (925 ± 46 ug/g) > Crassostrea gigas (852 ± 303 ug/g) > Meretrix lusoria (323 ± 265 ug/g) > Barbatia virescens (125 ± 24 ug/g) > Perna viridis (101 ± 64 ug/g); Cu, C. gigas (224 ± 172) > M. lusoria (133 ± 177 ug/g) > P. viridis (112 ± 145 ug/g); Ni, B. virescens (294 ± 291 ug/g) > Paphia exarata (116 ± 87 ug/g); Pb, P. exarata (2.65 ± 0.85 ug/g) > C. gigas (1.92 ± 1.41 ug/g); Cd, C. gigas (15.0 ± 16.0 ug/g) > M. lusoria (10.3 ± 14.0 ug/g); Sn, C. gigas (10.4 ± 26.0 ug/g) > P. exarata (8.84 ± 4.66 ug/g); Cr, M. lusoria 6.71 ± 3.78 ug/g); and As, P. viridis (29.2 ± 27.8 ug/g). Extremely high values of Zn (1095 ug/g) and Cd (15.0 ug/g) with the second high values of Cu (259 ug/g) and Pb (2.26 ug/g) in C. gigas were observed in April 1996 in the Machu mariculture area. Finally, the results obtained by Xiamen University researchers have been compared and discussed.