Mercury concentrations in seafood and the associated risk in women with high fish consumption from coastal villages of Sonora, Mexico
Introduction
Mercury in the upper ocean has tripled since the beginning of the Industrial Revolution due to human activities (Lamborg et al., 2014). The circulation patterns that move cold, salty and dense water to the ocean depths also transport mercury from shallower depths; this natural process of mercury sequestration may soon become limited as increasing human inputs have been predicted to involve as much mercury in the next 50 years as in the previous 150 years (Lamborg et al., 2014). In addition, mercury previously released from human activities continues to cycle through the atmosphere, ocean and terrestrial systems for hundreds of years, constituting two thirds of total annual emissions to the atmosphere (Pirrone et al. 1996, 2009; Sunderland and Selin, 2013). Mercury is emitted to the atmosphere as inorganic Hg°, which is highly volatile, but it can be removed after oxidation to Hg(II) and deposition onto land and ocean (Boening, 2000). This species of Hg is then transformed to organometallic compounds such as methyl mercury (MeHg) under anaerobic conditions or by mercury methylating microorganisms (Jackson, 1991). Bacterial methylation process can also occur inside fish intestines, as was proven by Rudd et al. (1980). Measurements of dissolved gaseous mercury (DGM) made over the Pacific Ocean reported elevated concentrations of methylated Hg species present in the low oxygen waters of the equatorial Pacific, both MeHg and Me2Hg were identified and concentration and distribution reflected to some degree surface ocean productivity (Kim and Fitzgerald, 1986; Mason and Fitzgerald, 1990, 1991; Macdonald et al., 2008; Sprovieri et al., 2009). This methylated form of Hg is highly lipophilic and consequently accumulates in fatty tissues of marine organisms and biomagnifies in the food chain (Hall et al., 1997; Bodalay and Fudge, 1999; Dietz et al., 2000; Dabeka et al., 2011; Copat et al., 2014; Conte et al., 2015; Adel et al., 2016; Ferrante et al., 2017). According to the U.S.EPA (2011), Revised Risk Assessment of Hg the dominant human exposure pathway is through the consumption of fish that have bioaccumulated Hg and the main health effect is neurological deficits in children who were exposed to MeHg in utero primarily through maternal fish consumption (Davidson et al., 1996; Copat et al., 2014; Carocci et al., 2014; Llop et al., 2015).
It is well established that fish from higher trophic levels, accumulate more mercury (Penedo de Pinho et al., 2002; Cizdziel et al., 2002; Sampaio da Silva et al., 2005; Dabeka et al., 2011). In the Gulf of California, sharks (i.e. smooth hammerhead, pelagic thrasher, pacific sharpnose shark, dusky shark, scalloped hammerhead and whitenose shark) have been identified as having high mercury concentrations (>0.5 ppm total mercury or “THg”) in the Gulf of California (García-Hernández et al., 2007; Ruelas-Inzunza et al., 2008; Boucher, 2013; Bergés-Tiznado et al., 2015). However, the fishery of sharks and other predator species represent only 7% of all fish species harvested in Mexico (excluding small pelagic fish) (CONAPESCA, 2014). Some of these more highly consumed species are tuna, groupers, snappers, mullets, corvine, sole, tilapia, among others (CONAPESCA, 2014). Ruelas-Inzunza et al. (2011a) reported higher concentrations of mercury in piscivorous fish from the coasts of Sonora and Sinaloa compared with omnivores or herbivores fish, although concentrations not exceeded the maximum permissible levels (MPL). Authors also estimated a methyl mercury hazard quotient (HQ) for these species, considering an average national fish consumption rate of 25 g day−1, concluding that no risk was identified for these species, although, they recognized a greater potential risk in fishermen and their families due to higher fish consumption.
The Gulf of California contains world-ranked, high marine biodiversity, with ca. 6000 species of invertebrates, sharks, rays, fish, sea turtles, aquatic birds and mammals (Brusca et al., 2005). The Midriff Islands region, in the northern Gulf of California (Fig. 1), is a national key site for the industrial (small pelagic fish, shrimp) as well as small-scale and sport fisheries (Kira, 1999; Cisneros-Mata, 2010; Erisman et al., 2011). The small-scale and sport fisheries capture up to 70 different species (Moreno-Báez et al., 2012), of which an important portion are captured in the coastal and deep rocky reefs along the Baja California and Sonora states coasts and around the 45 islands and islets of the region. Studies indicate that mercury concentrations are not elevated at the Midriff Region of the Gulf of California in different biota (Cahill et al., 1998; García-Rico and Ramos-Ruiz, 2001; García-Hernández et al., 2015; Páez-Osuna et al., 2017). Therefore, the levels of Hg in the Midriff Region of the Gulf of California, from a human-food viewpoint, would be mostly below hazardous levels for human consumption. However, these levels will not stay the same in the future and conclusions relating the general population might not be the same for fishermen and their families who consume fish more regularly.
In this context, the three main objectives of the present study were: 1) to determine mercury concentrations in various commercial species of fish and shellfish from the central Gulf of California; 2) to describe the food consumption patterns of women from fishing villages of central and southern Sonora; and 3) to estimate the health hazards associated to dietary intake of methyl mercury in women from these communities.
Section snippets
Fish and shellfish collections
Collection of organisms were made with two efforts. The first one was from February 2008 to June 2009 at the central-east portion of the Gulf of California (Fig. 1). Sampling points were located at the proximity of Kino Bay, Tiburon Island and outside the boundaries of Isla San Pedro Martir Biosphere Reserve (ISPM-BR) (Fig. 1). Collection of fish were made by hook and line onboard a small-scale fishery boat. Species were identified, measured (total length) to the nearest mm and weighted to the
Concentrations of Hg in fish and shellfish
Total mercury concentrations in fish ranged from < DL (under detection limit) to 1.22 μg g−1, with a mean of 0.15 ± 0.19 μg g−1 (Table 1). Only 6% of the samples exceeded the maximum permissible level (MPL) of 0.5 μg g−1 methyl mercury (DOF, 2011), these samples were goldspotted sand bass, yellowtail jack and whiptail stingray. The species with the lowest mean Hg concentrations were queen corvina, orangemouth corvina and spotted sand bass (Table 1). It is important to note that for some of the
Conclusions
Mean concentrations of mercury in fish and shellfish from the central Gulf of California were in general lower than the MPL, however due to high frequency seafood consumption by women from fishing villages of the coast of Sonora, the risk of methyl mercury exposure was high. The age group that presented the highest risk were women of 40–49 years old, and the lowest risk were for women of 20–29 years old. There were two factors that mitigated the risks of methyl mercury exposure: 1) that the
Acknowledgements
The collection and process of fish was financed by Marisla Foundation grant No. 20110161, the Packard Foundation grant No. 2012-38182, Sandler Foundation grant No. 201220082 and Fondo Mexicano para la Conservación de la Naturaleza (FMCN). The training of fishermen for fish collection and the food frequency surveys were financed by North America Partnership for Environmental Community Action (NAPECA) of the Commission for Environmental Cooperation, contract No. 73002033.037. We also want to
References (93)
- et al.
Mercury, lead and cadmium in blue crabs, Callinectes sapidus, from the Atlantic coast of Florida, USA: a multipredator approach
Ecotoxicol. Environ. Saf.
(2014) - et al.
Heavy metal concentrations in edible muscle of whitecheek shark, Carcharhinus dussumieri (elasmobranchii, chondrichthyes) from the Persian Gulf: a food safety issue
Food Chem. Toxicol.
(2016) - et al.
Survey of total mercury and methylmercury in edible fish and invertebrates from Azorean waters
Mar. Environ. Res.
(1997) - et al.
Methyl mercury exposure in Swedish women with high fish consumption
Sci. Total Environ.
(2005) Ecological effects, transport, and fate of mercury: a general review
Chemosphere
(2000)- et al.
Hg concentrations and related risk assessment in coral reef crustaceans, mollusks and fish from New Caledonia
Environ. Pollut.
(2009) - et al.
Methyl mercury, total mercury, and selenium in snapper from two areas of the New South Wales Coast, Australia
Mar. Pollut. Bull.
(1990) - et al.
First data on trace elements in Haliotis tuberculata (Linnaeus, 1758) from southern Italy: safety issues
Food Chem. Toxicol.
(2015) - et al.
Mercury and selenium intake by seafood from the Ionian Sea: a risk evaluation
Ecotoxiology and Environmental Safety
(2014) - et al.
Contaminant concentrations in sport fish from san Francisco Bay, 1997
Mar. Pollut. Bull.
(2002)
Comparison of contaminants from different trophic levels and ecosystems
Sci. Total Environ.
Bioaccumulation of metals and biomarkers of environmental stress in Parablennius sanguinolentus (Pallas, 1814) sampled along the Italian coast
Mar. Pollut. Bull.
Isopods of the genus Ligia as potential biomonitors of trace metals from the Gulf of California and Pacific coast of Baja California peninsula
Ecotoxicol. Environ. Saf.
Mercury in the bivalves Crassostrea tulipa and Perna perna from Ghana
Mar. Pollut. Bull.
Selenium and mercury in widely consumed seafood from South Atlantic Ocean
Ecotoxicol. Environ. Saf.
The overlooked role of the ocean in mercury cycling in the Arctic
Mar. Pollut. Bull.
Integrating the spatial and temporal dimensions of fishing activities for management in the Northern Gulf of California, Mexico
Ocean and Coastal Management Journal
Temporal variation of blood and hair mercury levels in pregnancy in relation to fish consumption history in a population living along the St Lawrence River
Environ. Res.
Total mercury intake from fish and shellfish by Japanese people
Chemosphere
Effects of various cooking methods and food components on bioaccessibility of mercury from fish
Environ. Res.
Environmental status of the Gulf of California: a pollution review
Eearth-Science Reviews
Mercury accumulation in barred sand bass (Paralabrax nebulifer) near a large wastewater outfall in the southern California Blight
Mar. Pollut. Bull.
Regional differences in worldwide emissions of mercury to the atmosphere
Atmos. Environ.
Mercury bioaccumulation patterns in fish from the Iténez river basin, Bolivian Amazon
Ecotoxicol. Environ. Saf.
Distribution of mercury in adult penaeid shrimps from Altata-Ensenada del Pabellón lagoon (SE Gulf of California)
Chemosphere
Mercury in fish that are of dietary importance from the coasts of Sinaloa (SE Gulf of California)
J. Food Compos. Anal.
Mercury in muscle and liver of then ray species from Northwest Mexico
Mar. Pollut. Bull.
Contaminated fish consumption in California's Central Valley Delta
Environ. Res.
The mercury levels in crustaceans and cephalopods from peninsular Malaysia
Environ. Sci. Pollut. Res.
Atlantis Model Development for the Northern Gulf of California
Mercury and selenium in muscle and target organs of scalloped hammerhead sharks Sphyrna lewini of the SE Gulf of California: dietary intake, molar ratios, loads and human health risks
Arch. Environ. Contam. Toxicol.
Uptake of mercury by fish in an experimental boreal reservoir
Arch. Environ. Contam. Toxicol.
Synthesis Report on Mercury in Fish Tissues from Mexico
Macrofaunal biodiversity in the Gulf of California
Daily consumption of wild fish and game: exposures of high end recreationalists
Int. J. Environ. Health Res.
Mercury in commercial fish: optimizing individual choices to reduce risk
Environ. Health Perspect.
Elemental profiles in feather samples from a mercury-contaminated lake in Central California
Arch. Environ. Contam. Toxicol.
Mercury toxicity and neurodegenerative effects
Rev. Environ. Contam. Toxicol.
Mercury distribution in organs of fish species and the associated risk in traditional subsistence villagers of the Pantanal wetland
Environ. Geochem. Health
Mercury levels of seafood commonly consumed in Taiwan
J. Food Drug Anal.
The importance of fisheries in the Gulf of California and ecosystem-based sustainable co-management for conservation
Mercury concentrations in fish from lake Mead, USA, related to fish size, condition, trophic level, location and consumption risk
Arch. Environ. Contam. Toxicol.
Anuario Estadístico de Acuacultura y Pesca 2014
Perfiles de salud reproductiva México
Risk assessment for metals and PAHs by Mediterranean seafood
Food Nutr. Sci.
Levels of total mercury in predatory fish sold in Canada in 2005
Food Addit. Contam.
Cited by (25)
Mercury in fish tissues from the Galapagos marine reserve: Toxic risk and health implications
2023, Journal of Food Composition and AnalysisCitation Excerpt :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). M. olfax showed Hg concentrations like those found in M. jordani and M. rosacea in the Central Gulf of California (García-Hernández et al., 2007; 2018). On the other hand, the concentrations found in the individuals of S. violacea and P. clemensi in this study were higher than those obtained by Biffi et al., (2020) in Peru and Monteiro, Isidro & Lopes (1991) for P. kuhlii in Azores Islands, respectively.
Toxic metal and metalloid contamination in seafood from an eutrophic Brazilian estuary and associated public health risks
2022, Marine Pollution BulletinCitation Excerpt :When considering the maximum deviation, only shrimp consumption by the adult population was not indicative of health risks The existence of health risks indicated by the HI and HQ for some metals is extremely worrying, especially for the population aged 5, indicating that no shrimp, swimming crabs or squid should be consumed by this age group. This group is highly vulnerable due to two important factors, low body mass and immune system immaturity (Garcı́a-Hernández et al., 2018; Zamora-Arellano et al., 2017). Other studies have also identified health risks for child populations compared to adult populations (Andrew et al., 2016, Copat et al., 2014, Tang et al., 2009).
Baseline titanium levels of three highly consumed invertebrates from an eutrophic estuary in southeastern Brazil
2022, Marine Pollution BulletinMercury concentrations in Baja California Sur fish: Dietary exposure assessment
2021, ChemosphereCitation Excerpt :It is important to consider that there is higher fish consumption and larger meal sizes in coastal communities compared to inland communities. For example, García-Hernández et al. (2018) found that fish and shellfish consumption by women of coastal communities of Sonora was almost ten times higher (mean: 307 ± 325 g per day) than the national average, as a result of the availability and affordability of fishery products in these communities. In addition, they reported a high mean HQ (6.2 ± 6.8.)
Methylmercury's chemistry: From the environment to the mammalian brain
2019, Biochimica et Biophysica Acta - General SubjectsCitation Excerpt :The bioaccumulation and biomagnification of MeHg along the web chain can result in human exposure. The consumption of MeHg-containing fish represents a common route of exposure, especially in individuals that consume fish as their main protein food source [102–104]. Moreover, in specific human populations (e.g. Inuits in Canada), exposure to high levels of MeHg can occur after the ingestion of mammals and birds [105].