Mercury levels in four species of sharks from the Atlantic coast of Florida
نویسندگان
چکیده
Florida’s commercial and recreational shark landings represent a significant portion of the total U.S. Atlantic shark landings (NMFS, 1993). Shark landings have increased significantly during the past decade because human consumption of shark meat has become increasingly acceptable and because, in Asian markets, the demand for shark fins is very high— as are the prices paid for them (NMFS, 1993; Brown, in press). The east-central coast of Florida is an important area for commercial and recreational shark fishing, and a wide array of shark species, including those examined in this study, are landed in this region (Trent et al., 1997; FDEP1). Mercury, a toxic metallic element, has been shown to bioaccumulate in fish tissue, and therefore, fish can represent a major dietary source of mercury to humans (Phillips and Buhler, 1978; Turner et al., 1980; Lyle, 1986). Methylmercury is the most toxic form of mercury for humans to consume (Meaburn, 1978; NMFS, 1993) and essentially all mercury found in fish muscle tissue (>95%) is in the monomethyl form (CH3Hg)(Grieb et al., 1990; Bloom, 1992). Therefore, the measurement of total mercury provides an approximation of Mercury levels in four species of sharks from the Atlantic coast of Florida
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