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Total mercury concentrations in wahoo, Acanthocybium solandri, from Atlantic and Gulf of Mexico waters of the southeastern United States and the Bahamas.
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Wahoo, Acanthocybium solandri, are predatory oceanic fish that occur and are harvested in all tropical and subtropical oceans. Total mercury concentrations analyzed in dorsal muscle tissue of 208 wahoo from offshore waters of the southeastern United States and the Bahamas ranged from 0.021 to 3.4 mg/kg (wet weight), with a mean of 0.50 mg/kg (+/- 0...
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Context 1
... total of 208 wahoo collected from offshore waters adjacent to Florida and the Bahamas were analyzed (Table 1). Of this total, 182 fish were collected from the Atlantic Ocean offshore of Florida and the Bahamas, and the remaining 26 fish were collected in the eastern Gulf of Mexico in offshore waters adjacent to Florida. ...Similar publications
Abstract. Mercury (Hg) trophic transfer and bioaccumulation in fish from a mineimpacted,
eutrophic lake were examined in relation to foraging habitat, trophic position, and
size. Diet analysis indicated that there were clear ontogenetic shifts in foraging habitats and
trophic position. Pelagic diet decreased and benthic diet increased with increasi...
Citations
... However, A. solandri is classified as a general predator since it feeds on species in a more homogeneous way (Baque-Menoscal et al., 2012). The samples of A. solandri in the GMR showed concentrations similar to those obtained by Cai et al. (2007) and Adams (2010) in the Gulf of Mexico and the Atlantic coast of the United States. This may be due to similarities in their diet, being composed of prey from different habitats, and due to the oceanographic characteristics present in Galapagos that cause the aggregation of species from different environments (Frank et al., 2007). ...
Fishing is one of the most important economic and cultural activities in Galapagos and Hg presence in aquatic ecosystems is a serious problem for human health, so its concentrations should be studied. We sampled five demersal species (Caulolatilus princeps, Caulolatilus affinis, Mycteroperca olfax, Hyporthodus mystacinus and Pon-tinus clemensi) and four pelagic species (Coryphaena hippurus, Acanthocybium solandri, Thunnus albacares and Seriolella violacea) to evaluate Hg concentration in muscle, liver and gonads. Hg was analyzed by Cold Vapor Atomic Absorption Spectrophotometry with Flow Injection System (CV-AAS-FIAS). Demersal species had higher Estimated Weekly Intakes (EWI) of Hg than pelagic species. According to the Codex Alimentarius (1995), EFSA (2018), FDA (2021) regulations, and according to the regulations in Europe, A. solandri, P. clemensi, and H. mystacinus were found above the maximum allowed concentration (MAC) (0.65, 0.65 and 1.26 mg/kg wet weight, respectively) so they could not be ingested nor commercialized. The Margin of Safety (MoS) of these species was above 1, so they could pose a risk to human health. We hypothesize that the Hg concentrations found in the studied species could come from the volcanism of the archipelago, since no major sources of anthropogenic Hg contamination can be found in the islands.
... Overall, adult stingrays have higher Hg concentrations than young-of-the-year. This is consistent with the known relationship between Hg accumulation and growth in other elasmobranch species, which would result in larger sub-adult or adult individuals accumulating more Hg than young-of-the-year (Adams 2010;Adams and McMichael 1999;Nam et al. 2011;Rumbold et al. 2014). ...
... When comparing stingrays sampled in this study to stingrays sampled in 1994, individuals in this study had significantly lower concentrations of total Hg in muscle. This suggests that bioavailable Hg is decreasing within the IRL, where previous studies have reported high Hg concentrations in species that occupy upper trophic positions, including sharks and marine mammals (Adams 2010;Adams and McMichael 1999;Durden et al. 2007;Schaefer et al. 2015). Total Hg concentrations in large apex predators, such as bottlenose dolphins (Tursiops truncatus), have also shown a similar decrease over time in the IRL (Schaefer et al. 2015). ...
Mercury (Hg) deposited into aquatic sediments can be converted into the more toxic methylmercury (MeHg) by microbial activity. Atlantic stingrays (Hypanus sabinus) are an estuarine and nearshore species found in coastal regions of the western North Atlantic, occurring in multiple habitat types, and feeding mainly on benthic invertebrates. Mercury dynamics and speciation in stingrays have not been well examined. This study quantified total Hg and Hg species (Hg (II) and MeHg) in Atlantic stingrays sampled from Florida’s Indian River Lagoon (IRL) from 2012 to 2013. Tissues (muscle and liver) collected from 29 stingrays were lyophilized and homogenized before being analyzed using a direct mercury analyzer. Concentrations of total Hg in muscle were positively related to stingray disk width, but concentrations in liver were not. Mean (±SD) total Hg in muscle (0.56 ± 0.30 mg/kg dw) was significantly higher than mean total Hg in liver (0.23 ± 0.19 mg/kg dw). Within liver tissue, percent MeHg (of total Hg) ranged from 31 to 99%. The ratio between total Hg in liver and total Hg in muscle was <1 for nearly all individuals, suggesting a lack of active hepatic demethylation and sequestration mechanisms. Concentrations of Hg in IRL Atlantic stingrays fall below concentrations known to result in direct toxicity to fishes; however, effects thresholds are not well understood for elasmobranchs. Comparisons of Hg concentrations in IRL Atlantic stingrays sampled previously (37 individuals in 1994) indicate that total Hg concentrations in muscle of Atlantic stingrays have decreased over the past two decades, suggesting a reduction in the bioavailable Hg in the IRL ecosystem.
... Dolphinfish and wahoo did not exhibit THg Wet concentrations above current guidelines set by various government bodies (US Environmental Protection Agency [EPA] = 0.3 ppm, US Food and Drug Administration [FDA] = 1.0 ppm) and fell within expected ranges reported in previous studies (e.g. Adams 2009Adams , 2010. However, reported concentrations are not negligible, and prolonged, consistent exposure may still allow for accumulation of relatively high Hg levels in human consumers (e.g. ...
Identifying prey resource pools supporting fish biomass can elucidate trophic pathways of pollutant bioaccumulation. We used multiple chemical tracers (carbon [δ13C] and nitrogen [δ15N] stable isotopes and total mercury [THg]) to identify trophic pathways and measure contaminant loading in upper trophic level fishes residing at a reef and open-ocean interface near Eleuthera in the Exuma Sound, The Bahamas. We focused predominantly on the trophic pathways of mercury bioaccumulation in dolphinfish Coryphaena hippurus and wahoo Acanthocybium solandri, two commonly consumed pelagic sportfish in the region. Despite residing within close proximity to productive and extensive coral reefs, both dolphinfish and wahoo relied almost exclusively on open-ocean prey over both short and long temporal durations. A larger isotopic niche of dolphinfish suggested a broader diet and some potential prey partitioning between the two species. Mean THg concentrations in dolphinfish (0.2 ± 0.1 ppm) and wahoo (0.3 ± 0.3 ppm) were mostly below recommended guidelines for humans (US EPA = 0.3 ppm, FDA = 1.0 ppm), and were within ranges previously reported for these species. However, high THg concentrations were observed in muscle and liver tissue of commonly consumed reef-associated fishes, identifying a previously unrecognized route of potentially toxic Hg exposure for human consumers on Eleuthera and neighboring islands.
... As diet is the main source of these contaminants, it is important to study the feeding ecology of these top predators to identify potential pathways of metal transfer within marine food-webs Kiszka et al., 2015). The degree of piscivory (Adams, 2010), length prey size in regional diets (Suk et al., 2009) and geographic variability in bioavailability (Verdouw et al., 2011) influence accumulation rates and tissue concentration. Hence, information from stomach contents and stable isotope analyses, representing respectively short and long-term feeding habits, can be used to more comprehensively characterize these pathways, particularly in highly migratory predator fishes. ...
Heavy metals are a hazard to marine fauna and human health. In this study we assess stable isotopes and metal content in Prionace glauca and Isurus oxyrinchus and analyse these results within and among other species and across regions and geographical areas. Also, we evaluate their suitability, together with Raja clavata and Galeorhinus galeus, as Mid-Atlantic bioindicators. Prionace glauca and I. oxyrinchus shared the same trophic level in a pelagic food web and did not present significant differences between genders or metals, except for As. Arsenic and Hg accumulated while Cd and Pb were not detected. One I. oxyrinchus presented Hg values above regulatory limits. A high Hg exposure was associated with I. oxyrinchus since its maximum weekly intake was exceeded. Elasmobranchs can be used as metal sentinels, each presenting different key features which defines a good marine bioindicator, allowing long-term monitoring at different temporal and spatial scales.
... As diet is the main source of these contaminants, understanding the feeding ecology of these species is required to identify potential pathways within food-webs (Taylor et al., 2014). The degree of piscivory (Adams, 2010), length prey size in regional diets (Suk et al., 2009) and geographic variability in bioavailability (Verdouw et al., 2011) also influence accumulation rates and tissue concentration. In this context, information regarding diet, such as stomach contents and/or stable isotope analyses, can and should be used to comprehensively characterize these pathways (Kiszka et al., 2015). ...
The goal of this study was to assess stable isotopes profiles, metals concentration and PCBs in Raja clavata muscle and liver, according to sex and size, and to elucidate its suitability as a Mid-Atlantic biomonitor. The results reflected bioaccumulation and suggested biomagnification processes for As and Hg in muscle tissue. Cd, Cu and Zn were detected in high amounts in liver, Cr, Mn and Rb were relatively stable and low, Pb was not detected and Sr was present in muscle at high levels, decreasing with length. Hg and Se were strongly correlated, suggesting a mitigation role. Both tissues presented low concentrations of PCBs, especially the dioxin-like congeners, although always higher in liver and not correlated with size. None of these contaminants exceed EU legislated limits. However, they need to be monitored given study area's location, volcanic nature and the expected increase of anthropogenic activity related to future prospective mining activities and the establishment of the Transatlantic Trade and Investment Partnership (TTIP) between Europe and the USA.
... Certain aspects of feeding ecology, such as the degree of piscivory and average prey size in regional diets, are potential indicators of predator mercury concentrations. Piscivorous predators have been shown to have higher concentrations of mercury in their tissues compared to those that feed on invertebrates and other lower trophic level prey (de Pinho et al., 2002;Adams, 2010). Prey size can also affect mercury bioaccumulation of predators, as larger prey are often older and/or feeding at higher trophic levels, thus carrying greater mercury burdens (Piraino and Taylor, 2009;Suk et al., 2009). ...
... Total mercury concentrations of dolphinfish, tunas, and sharks harvested in offshore waters of southern New England were positively related to predator body size by weight and length, trophic level (approximated by d 15 N values), the degree of piscivory and mean prey size in their respective diets. This information complements mercury evaluations previously conducted in more southern regions including the Gulf of Mexico, the eastern Atlantic, Pacific Ocean and the South Atlantic Bight of the northwest Atlantic Ocean (Besada et al., 2006;Kojadinovic et al., 2006;Cai et al., 2007;Kaneko and Ralston, 2007;Suk et al., 2009;Adams, 2009Adams, , 2010Burger and Gochfeld, 2011;Ordiano-Flores et al., 2012). Mercury levels in southern New England were relatively high in all fishes, and exceeded the US EPA recommended threshold of 0.3 ppm (US EPA, 2010) in 100% of mako sharks and 63% of all other predators examined in this study. ...
... The general ability of fish to metabolize and eliminate mercury after uptake from their environment is limited (Trudel and Rasmussen 1997). Therefore, mercury levels are greatest in larger and older individuals and among upper-trophic-level pelagic (Cai et al. 2007;Adams 2010) and demersal (Adams and Onorato 2005;Bank et al. 2007) fish species in the Gulf of Mexico. ...
We analyzed total mercury concentration in muscle tissue of 15 serranid species (n = 1,401 fish) collected from the Gulf of Mexico and also developed a comprehensive model relating two commonly used mercury analysis methods. There was considerable interspecific and intraspecific variability in mercury within groupers and sea basses. Mean mercury concentration for individual species ranged from 0.03 to 0.91 mg/kg wet weight across all size ranges, and for legally harvestable grouper and sea bass concentrations were 0.32 mg/kg and 0.09 mg/kg, respectively. Mercury in individual fish ranged from 0.01 to 3.3 mg/kg. Approximately 23% of all grouper samples analyzed contained mercury at concentrations that exceeded the U.S. Environmental Protection Agency's methylmercury consumption guidance criterion for humans (0.3 mg/kg). Mercury in legally harvestable individuals of some species exceeded 0.5 mg/kg, and harvestable black grouper Mycteroperca bonaci had a mean mercury concentration greater than 1.0 mg/kg. A positive relationship was observed between total mercury content and both fish length and fish age. For species that feed principally on fishes (e.g., gag M. microlepis and scamp M. phenax), mean mercury concentration was greater than that for species that feed mainly on invertebrates (e.g., red grouper Epinephelus morio and sand perch Diplectrum formosum). Although overall mean mercury concentrations were relatively low, for six species the maximum mercury concentration was at a level that has been associated with sublethal effects on fish physiology and with human health risks. Current grouper management regulations in the Gulf of Mexico select for a fishery of the largest and oldest individuals, which have the greatest mercury burdens. The species- and size-specific mercury data from this study can be used to inform at-risk human populations, refine regional fish consumption advisories, and further our understanding of mercury bioaccumulation in these important fishery species.Received October 20, 2011; accepted April 2, 2012
... Although it should theoretically be simple to quantify the relative distribution and bioavailability of a given substance in pelagic waters by knowledge of its lipid-solubility (and hence affinity for organic material), complex biotic and abiotic processes results in concentrations of contaminants in water, particles or organisms that are difficult to predict (e.g., Ruus et al. [5], Vethaak et al. [6]). The available data support some general observations; for example, bioaccumulation and possible biomagnification of polycyclic aromatic hydrocarbons in invertebrate food chains, but not in vertebrates [7,8,9] (but see Berrojalbiz et al. [10]), trophic transfer of persistent organic contaminants [11,12,13,14] and mercury [15,16], and finally, more or less species-and exposure-dependent accumulation of other trace metals [17,18]. ...
Abstract: Most of the primary production of the world's oceans takes place in the water column, thereby fuelling not only marine pelagic food-webs, but also most benthic communities. In addition, nearly all marine organisms depend on the pelagic zone for some part of their life-cycle. Although most contaminants have physico-chemical properties that cause them to associate with organic material particles and eventually be transported to sediments, direct contaminant inputs are predominantly to pelagic ecosystems. Taking both the ecological importance and the contaminant load into account, there is a surprising lack of scientific knowledge concerning the effects of contaminants in pelagic systems. The main reasons are presumably the difficulty in linking exposure with processes at a scale relevant for environmental management, and challenges involved in using pelagic fish and zooplankton species for experimental studies (excluding the 2-3 copepod species used for regulatory toxicity testing). Contaminants have been shown to affect primary producers as well as secondary producers-consumers, but there is very limited knowledge about ecological impacts. Top predators in marine ecosystems (piscivorous fish species, marine mammals, seabirds) will be particularly at risk from persistent organic contaminants since they will biomagnify. Although there is evidence of effects caused by such substances in the past, there is a need for continuous updates including “new” contaminants. Most relevant for lower trophic levels, micro- and mesocosm studies under controlled conditions are critical for increased understanding of processes and putative effects of contaminants in the pelagic zone. Some field-based strategies have been suggested and implemented to varying degrees for environmental management of contaminants in the water column, including risk- based modelling, bioassay-analyses of environmental samples or extracts (e.g., through the use of passive samplers), caging of organisms and, finally, collection and analyses of native organisms.
... Although it should theoretically be simple to quantify the relative distribution and bioavailability of a given substance in pelagic waters by knowledge of its lipid-solubility (and hence affinity for organic material), complex biotic and abiotic processes results in concentrations of contaminants in water, particles or organisms that are difficult to predict (e.g., Ruus et al. [5], Vethaak et al. [6]). The available data support some general observations; for example, bioaccumulation and possible biomagnification of polycyclic aromatic hydrocarbons in invertebrate food chains, but not in vertebrates [7,8,9] (but see Berrojalbiz et al. [10]), trophic transfer of persistent organic contaminants [11,12,13,14] and mercury [15,16], and finally, more or less species-and exposure-dependent accumulation of other trace metals [17,18]. ...
Ecological Impacts of Toxic Chemicals presents a comprehensive, yet readable account of the known disturbances caused by all kinds of toxic chemicals on both aquatic and terrestrial ecosystems. Topics cover the sources of toxicants, their fate and distribution through the planet, their impacts on specific ecosystems, and their remediation by natural systems. Each chapter is written by well-known specialists in those areas, for the general public, students, and even scientists from outside this field. The book intends to raise awareness of the dangers of chemical pollution in a world dominated by industry and globalization of resources. Because the problems are widespread and far reaching, it is hoped that confronting the facts may prompt better management practices at industrial, agricultural and all levels of management, from local to governmental, so as to reduce the negative impacts of chemical contaminants on our planet.
Marine fish species are an important source of biologically valuable proteins, fats, fat-soluble vitamins, and n-3 polyunsaturated fatty acids, but they are also susceptible to pollutants. Mercury is liable to bioamplify in the aquatic food chain, and the health risks posed by methylmercury (MeHg) could undermine the benefits of eating fish, so risk-benefit assessments are needed for those fish species regularly consumed. The purpose of this study was to analyze the concentrations of mercury and characteristics of fatty acids in marine fish harvested from Liaodong Gulf, China, so as to better understand the risk-benefit effects of marine fish consumption. We found that the ratio of MeHg to total Hg (THg) was normally distributed. The concentrations of THg and MeHg in marine fish muscles (14 species, a total of 239) ranged from 0.920 to 0.288 μg/g and 0.050 to 0.192 μg/g, respectively. There were no significant interannual differences in the muscles' concentrations of MeHg and THg, or of their fatty acids (p > 0.05). The proportion of total saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) varied significantly among different marine fish-feeding habits (predacious, omnivorous, benthivorous and planktivorous), but the differences between polyunsaturated fatty acids (PUFAs) were not significant, which may be due to the undistinguished fatty acids (p < 0.05). The risk-benefit assessment using the intelligence quotient (IQ) scoring model revealed that all the studied marine fish had positive effects on child IQ under different consumption scenarios. Additionally, the integrated risk-benefit analysis for adult cardiovascular health showed that all the studied marine fish, but especially Ditrema temmincki Bleeker, are capable of reducing the relative cardiovascular risk posed by the MeHg in the fish. We conclude the positive effects of eating common marine fish from the Liaodong Gulf far outweigh their negative ones.
