Quantification and Speciation of Mercury and Selenium in Fish Samples of High Consumption in Spain and Portugal

Abstract

Mercury (Hg) and selenium (Se) determinations were carried out to evaluate human exposure to those elements through fish consumption in Spain and Portugal. Atomic fluorescence spectroscopy (AFS) was applied in a cold vapor mode for total mercury quantification and was also hyphenated to gas chromatography (GC) to achieve the speciation of organomercurial species in fish samples. The results obtained show the highest concentration of Hg in swordfish and tuna (0.47+/-0.02 and 0.31+/-0.01 microg g-1, respectively), and a much lower concentration in sardine, mackerel shad, and octopus (0.048+/-0.002, 0.033+/-0.001, and 0.024+/-0.001 microg g-1, respectively). The determination of alkyl mercury compounds revealed that 93-98% of mercury in the fish samples was in the organic form. Methylmercury (MeHg) was the only species found in the three fish species with higher mercury content. Total selenium concentration was high in sardine, swordfish, and tuna (0.43+/-0.02, 0.47+/-0.02, and 0.92+/-0.01 microg g-1, respectively), but low in mackerel shad and octopus (0.26+/-0.01 and 0.13+/-0.01 microg g-1, respectively). Speciation of selenium compounds was done by high-performance liquid chromatography in conjunction with inductively coupled plasma mass spectrometry (LC-ICP-MS). Selenomethionine (SeMet) was the only selenium compound identified in the fish samples with higher selenium content. Among the fish species studied, sardine had the most favourable Se:Hg and SeMet:MeHg molar ratios; therefore, its consumption seems to be preferable.

Mercury contamination and life history traits of Allis shad Alosa alosa (Linnaeus, 1758) and Twaite shad Alosa fallax (Lacépède, 1803) in the Gironde estuary (South West France)

“…Our results for Twaite shad are consistent with an accumulation of [Hg] as fish get larger (Baeyens et al, 2003;Agusa et al, 2004) and is reinforced by the lower [Hg] in smaller Twaite Cabañero et al (2005) Herring (Clupea harengus) Atlantic ocean 0.20 b Cossa et al (1990) a Dry weight data calculated from fresh weight data according to the relation: 2.5 lg g -1 dry weight or 0.5 lg g -1 wet weight (WHO, 1990) shad collected by Durrieu et al (2005a) (e.g.…”

Biochemical and physiological modifications in tissues of Sardina pilchardus: spatial and temporal patterns as a baseline for biomonitoring studies

“…The physiological condition of S. pilchardus seems to be linked to its reproductive cycle (Amenzoui et al, 2006;Garrido et al, 2008;Nunes et al, 2011). Literature on the use of S. pilchardus as an environmental sentinel has shown its contamination by anthropogenic compounds, namely metals (Canli and Atli, 2003;Cabañero et al, 2005;Falcó et al, 2006), but also polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and pesticides (Amado et al, 2006;Antunes et al, 2007;El Morsy et al, 2013). Some of these compounds, namely organochlorine pesticides, are not used in oceanic areas, and their presence in tissues of sardines captured at mid-Atlantic area (Azores Islands) demonstrates the global dispersion, and the validity of using S. pilchardus as an adequate tool to diagnose the presence of persistent anthropogenic compounds in the marine environment (Magalhães and De Barros, 1987).…”

Selenium and Mercury in Pelagic Fish in the Central North Pacific Near Hawaii

“…Whereas it is well documented that seafoods contain from nondetectable to low levels of Hg [2][3][4][5][6][7], the potential for adverse health effects from the normal low level Hg exposure from eating ocean fish remains controversial [1,[8][9][10][11][12]. By contrast, nearshore and freshwater fish may pose a greater health risk because of the proximity to and potential for greater Hg accumulation traced to anthropogenic sources.…”

“…The Hg/Se molar ratio tends to be quite low in the edible muscle of most commercially important ocean fish [3,6,40]. This may be because ocean fish are among the richest dietary sources of Se, comprising 17 of the top 25 sources in the American diet [41].…”