Concentrations of lead in some coastal fishes from the Baltic Sea

Abstract

INTRODUCTION In contrast to other harmful metals, as e.g. mercury and cadmium, the concentrations of lead in coastal fishes from the Baltic Sea have attracted far less attention (e.g. von Westernhagen and Bignert, 1996; Jezierska and Witeska, 2001; Szefer, 2002; Pokorska et al., 2012; Nyberg et al., 2013; Boalt et al., 2014) although effects of this toxic metal on humans (e.g. Guinnee, 1972; Bremner, 1974; Brian et al., 1980; IPCS, 1989; ATSDR, 2005), fishes, mammals, and birds (e.g. Haider, 1964, 1977; NRCC, 1979; Atchison et al., 1987; Eisler, 1988; Hofer and Lackner, 1995; Pain, 1996; Dietz et al., 1998) have been documented. Considering the significant inflow of lead into the sea and over its vast drainage area (e.g. Ruhling et al., 1992; HELCOM, 1997, 2003, 2010; Bartnicki et al., 2000; Buse et al., 2003) this is rather surprising. In the 1970s some investigations on the concentrations of lead in certain species of Baltic fish, mainly Baltic herring (Clupea harengus membras L.) and cod (Gadus morhua callaris L.), were performed (e.g. Lehtonen, 1973; Voipio et al., 1977; Tervo et al., 1980; Perttila et al., 1982), followed by attempts at its monitoring, mainly in the muscle tissue of herring and in the liver of cod, for the Baltic Marine Environment Protection Commission (Helsinki Commission, HELCOM) by some Baltic national research institutes, e.g. the Finnish Institute of Marine Research (Haahti, 1991), the Swedish Museum of Natural History (Jorhem and Sundstrom, 1993), and the Estonian Marine Institute (Jankovski et al., 1996). In the southern Baltic Sea similar investigations additionally included sprat (Sprattus sprattus balticus Schn.), flounder (Platichthys flesus L.), perch (Perca fluviatilis L.), and some other species (Falandysz and Lorenc-Biala, 1984). After confirmation that lead mainly concentrates in internal organs, such as kidney and liver, and bone tissue of fish (e.g. Reichenbach-Klinke, 1980), and not in muscle tissue like mercury, the interest in such monitoring declined significantly, especially because the observed concentrations of lead in the muscle tissue of fish were far below the accepted security levels for fish as food for human consumption (e.g. Nuutamo et al., 1980; Haahti, 1991; Tahvonen and Kumpulainen, 1996; Leivuori, 2007). Starting again in the 1980s, monitoring of the concentrations of lead has been continued, with mainly liver and muscle tissue of herring studied (e.g. Jankovski et al., 1996; Roots and Simm, 2002; Lind et al., 2006; Leivuori, 2007). The present study focuses on the concentrations of lead in the muscle tissue and some internal organs, mainly liver, but in some cases also in gonads, kidneys, spleen, and bile, of some representative coastal fish species from various parts of the Baltic Sea, including two coastal inlets in SW Finland (isolated in the late 1950s from the Baltic Sea). The aim is to survey and to compare the concentrations of lead in the similar fish species as in previous studies from various parts of the Baltic Sea (Voigt, 1999, 2000a, 2000b, 2003, 2004, 2008a, 2008b, 2013). MATERIAL AND METHODS Some abundant coastal fish species (adults and mainly of comparable size for each species separately, with the exception for the fishes from two isolated freshwater reservoirs, see below) from various parts of the Baltic Sea (Fig. 1) were sampled in the autumn season during the years 1997-2006 for analysis of concentrations of lead in muscle tissue and some internal organs, mainly liver and gonads. Besides bow-nets and gillnets trawling was used for sampling. The following five fish species were focused upon: * Baltic herring, sampled from Peimari-Pemarn in the Finnish Archipelago Sea ([Angstrom]-AS), Tvarminne area at the Finnish SW coast of the Gulf of Finland (H-Tva), and Vaike Vain Strait at the western Estonian coast (VV); * smelt (Osmerus eperlanus L.) from the rivermouth area of the Kokemaenjoki-Kumoalv in the Bothnian Sea (RKK), Peimari-Pemarn (A-AS), Tvarminne (H-Tva), Vaike Vain (VV), and south-western coastal freshwater basin of Pargas-Parainen (PP); * perch from Tvarminne (H-Tva), Vaike Vain (VV), Pargas-Parainen (PP), and the southern coastal freshwater basin of Gennarby (Gby); * eelpout (Zoarces viviparus L. …