Rock-Shells ( Thais clavigera ) as an Indicator of As, Cu, and Zn Contamination on the Putai Coast of the Black-Foot Disease Area in Taiwan

Abstract

This study presents the distribution of arsenic (As), copper (Cu), and zinc (Zn) in various seafoods-oysters (Crassostrea gigas), false fusus (Hemifuscus tuba), venus clams (Cyclina sineasis), green mussels (Perna viridis), blood clams (Arca granosa), flounders (Psettodes erumei), and rock-shells (Thais clavigera) collected from the Putai coast of the black-foot disease (BFD) area in Taiwan. Special attention is paid to evaluate the relationships among As, Cu, and Zn and effect of body size on metal concentration in Thais clavigera. Maximum Zn and Cu geometric mean (GM) concentrations (GM = 615 and 376 microg/g, dry wt, respectively) are found in oysters (Crassostrea gigas), and the values are much higher than those of the other organisms by about 1.7-208 and 1.8-375 times, respectively. Similarly, Thais clavigera has a high capacity for accumulating Cu and Zn collected from the same location. One interesting point is that relatively high As concentrations (GM = 65.7 microg/g, dry wt) in Thais clavigera are found as compared with those in other organisms (range from GM = 2.37 to 40.2 microg/g, dry wt). The As concentrations are significantly higher in Thais clavigera (1.62-27.7 times) than those in other organisms (p < 0.05), except for the false fusus (Hamifuscus tuba). A linear regression analysis shows a significant increase in Zn concentration with increasing Cu concentration in Thais clavigera. On the other hand, the As concentration is correlated with Cu and Zn concentrations (r = 0.77 and 0.77, respectively; p < 0.05) in Thais clavigera. Double logarithmic plots of metal content and concentration against dry-body weight and shell length show linear relationships. The result indicates that large individuals have higher contents of Cu, Zn and As, and have slopes of 1.58, 1.38, and 1.34, respectively. In addition, metal concentrations against shell length for all animal sizes also indicate that Cu, Zn and As have slopes of 1.92, 1.18, and 1.11, respectively. In conclusion, Thais clavigera has a high capactiy for accumulating As, Cu, and Zn and is a potential bioindicator for monitoring As, Cu and Zn.

Heavy Metal Concentration from Biologically Important Edible Species of Bivalves (Perna viridis and Modiolus metcalfei) from Vellar Estuary, South East Coast of India

“…Cr in sediment was ranging between 7.10 µg/g and 31.44 µg/g and Cu concentration ranged from 11.28 µg/g to 37.24 µg/g and Zn concentration (36.14 to 56.14 µg/g) the sediment of Vellar estuary. Likewise copper in sediments collected from the Lukang culture area of central Taiwan and also evaluates the relationship by purble clams (Hiatula diphos) and venus clams (Gomphina aguilatera) [14].…”

Estimation of Target Hazard Quotients and Potential Health Risks for Metals by Consumption of Seafood in Taiwan

“…All samples were digested using a microwave digester (Model MDS-2000) with a mixture of nitric and sulfuric acids (1/1, v/v) solution, and the supernatant analyzed for copper and zinc by flame atomic absorption spectrophotometry (Han and Hung 1990). Lead, cadmium, arsenic, and mercury were measured by graphite atomic absorption spectrometry (GAAS) using nickel (for arsenic) and TeO 2 (for mercury) as matrix modifiers, and standard addition procedures were used for the calculation of the analyte concentrations (Han et al 1997).…”

“…The results generated were, in most cases, in good agreement with certified values. Standard reference materials (SRM 1566a Oyster Tissue and IAEA 350 Tuna Fish Tissue) were analyzed at regular intervals (Han et al 1996(Han et al , 1997.…”

“…For noncarcinogenic effects, risk is expressed as a target hazard quotient, the ratio between the exposure and the reference dose. The models for estimating target hazard quotients and target cancer risks (lifetime cancer risks) are: (Han et al 1997).…”

“…The high mobility and bioavailability of dissolved arsenic may be easily taken up by humans. However, there is little information on the concentrations of arsenic in different seafood from coastal water of the BFD (Putai) area in Taiwan (Han et al 1997).…”