PRODUCTION OF METHYLMERCURY IN HG(II) ION-ADDED FLOODED PADDY FIELD SOIL AND ITS ACCUMULATION IN RICE
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Recent studies have shown that rice is a significant source of dietary exposure to methylmercury (MeHg) for humans. The use of Hg in artisanal and small-scale gold mining (ASGM) has increased in many developing countries in rice-producing regions worldwide. The Hg released into rice paddy fields as a result of ASGM activity pollutes the paddy soil. Anaerobic soil bacteria in flooded rice paddy synthesize MeHg from Hg, leading to accumulation of MeHg in the rice plants. However, MeHg production from inorganic Hg in flooded paddy soil and its bioaccumulation in rice plants have not been extensively studied thus far. Here, we prepared different samples of Hg(II) ion-contaminated soils and cultivated rice therein, to confirm the differences in MeHg production in soils and its effect on MeHg accumulation in rice grain.
Pot experiments were performed in two different soil types—soil I and soil II, to each of which 10 mg/kg Hg(II) ion was added. Although the soils were well mixed under flooded condition, the vertical distribution of T-Hg concentration in these soils was not uniform, with higher concentrations in the upper layer and drastically reduced concentrations below. Rice was planted on June 12, 2015 and harvested on November 16. The flooded condition was maintained throughout the rice-growing season; the surface layer soil (about 3-cm thickness) and leaf and ear samples were collected every month. T-Hg and MeHg concentrations in these samples were measured using thermal decomposition-CV-AAS and HPLC-chemiluminescence method, respectively.
T-Hg and MeHg concentrations in the surface layer soil were monitored during the rice-growing season. MeHg production was confirmed in soil I after two weeks but in soil II after 3 months (October). The maximum MeHg concentration of soil I was 0.13 mg/kg in August and that of soil II was 0.11 mg/kg in October. MeHg concentrations in the flooded paddy soil showed wide variations. MeHg concentrations in the ear samples of brown rice from soil I and soil II were 0.52 ± 0.08 mg/kg (n=87) and 0.22 ± 0.03 mg/kg (n=96), respectively. MeHg and T-Hg concentrations were measured in all three parts of the brown rice grain—embryo, bran, and endosperm and found to be 3.18 and 3.86 mg/kg, 0.74 and 0.90 mg/kg, and 0.49 and 0.53 mg/kg, respectively. These results would be presented in detail in our subsequent study.
QUANTIFYING THE HEALTH IMPACTS OF DIETARY FISH CONSUMPTION ADVISORIES FOR METHYLMERCURY AMONG INUIT IN LABRADOR
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Traditional diets of northern indigenous populations are rich in birds, fish and marine mammals, leading to high exposures to methylmercury (MeHg) and polychlorinated biphenyls (PCBs). Dietary advisories restricting consumption of local traditional foods are the predominant tool used to reduce risks associated with bioaccumulative contaminants. However, traditional foods contribute disproportionately to overall intakes of vitamin D, omega-3 fatty acids and other essential nutrients, and the transition to diets based on store-bought foods has been linked to adverse health outcomes including increased rates of obesity, cardiovascular disease and diabetes. Therefore, dietary advisories must weigh the risks posed by increased exposures to bioaccumulative contaminants against the risks posed by the loss of key nutrients, which act alternately on cardiovascular, neurodevelopmental and oncogenic endpoints. We quantify for the Inuit of Labrador, Canada the significance of local and store-bought foods to the overall dietary calories, MeHg, PCBs and a suite of nutrients. While local foods account for only 10% of total calories, they are the main source of MeHg (70%), PCBs (>90%) and a disproportionate source of omega-3 fatty acids (36%) and vitamin D (39%). We construct scenarios to forecast the cardiovascular, neurodevelopmental, cancer and nutritional impacts of substituting store-bought foods for local foods in comparison to the risks posed by increasing levels of MeHg. We find that substituting store-bought foods for local foods to preserve baseline MeHg exposures can reduce but not completely eliminate neurological impacts on developing children. However, the relative risk of cardiovascular death is greater for store-bought food substitution scenarios (population mean < 1.5) than the baseline diet for MeHg increases in local foods up to roughly seven times the baseline measured values. Food substitution scenarios generally increase population-wide cancer risks (population mean relative risk < 1.1, hepatic and colorectal cancers) relative to baseline and are associated with a decline in sufficiency of key nutrients (e.g., iron, phosphorus) of < 10% required daily intake. This work demonstrates that dietary advisories alone cannot be used to mitigate risks associated with increased exposures to MeHg and, in many cases, may increase these risks.
SELENIUM-INDUCED REDUCTION IN METHYLMERCURY ACCUMULATION IN RICE: ANTAGONISTIC INTERACTION IN SOIL OR WITHIN PLANT
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Methylmercury (MeHg) accumulation in rice has great implications for human health. Here, effects of selenium (Se) on MeHg availability to rice are explored by growing rice under soil or foliar fertilization with Se. Results indicate that soil amendment with Se could reduce MeHg levels in soil and grain (maximally 73%). In contrast, foliar fertilization with Se (examining MeHg-Se interactions within plant) enhanced plant Se levels (312 folds) without affecting grain MeHg concentrations. These evidences, along with distinct distribution of MeHg and Se within plant, demonstrate for the first time that MeHg-Se antagonism in soil (i.e., reduced soil MeHg due to Se) rather than MeHg-Se interactions within plant might be the key process triggering the decreased grain MeHg levels under Se amendment. The observed MeHg-Se antagonism in soil could be mainly attributed to the formation of Hg-Se complexes (detected by TEM-EDX and XANES) and thus reduced microbial MeHg production. Moreover, selenite and selenate were equally effective in reducing soil MeHg concentrations, possibly because of rapid changes in Se speciation. The dominant role of Se-induced reduction in soil MeHg levels, which has been largely underestimated previously, together with the possible mechanisms advance our mechanistic understanding about MeHg dynamics in soil-rice systems.
MERCURY IN 15 DEEP SEA FISH SPECIES FROM THE NORTHEAST ATLANTIC AND FOOD SAFETY CONSIDERATION
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Previous studies have shown that tusk (Brosme brosme) is a species which seems to accumulate relatively high concentrations of mercury. Levels of mercury in tusk have exceeded the EUs maximum level for food safety in some fjord- and coastal areas. There has therefore been a need for a comprehensive survey of mercury levels in tusk caught in different geographical areas. There has also been a knowledge gap about the level of mercury in common ling (Molva molva) and other deep sea species caught in the same areas as tusk. During 2013-2016, 1396 tusk were sampled at 64 positions, distributed on fjord, coast and open sea areas from the Barents Sea in the north to the Skagerrak in the south and from Iceland in the west to Eastern Finnmark in the east. Additionally, 822 common ling were sampled from 41 positions, and 554 individuals of 15 different species were taken as bycatch. Fillets from each fish were analysed for a range of metals, including total mercury (Hg).
The results verified that mercury levels are relatively high in tusk fillet, with a total average of 0.34 mg/kg wet weight and mean concentrations above the maximum level of 0.5 mg/kg wet weight in fjords in western Norway, on the Skagerrak coast and in the Vestfjord area. Moreover, mean concentrations of 0.2 mg/kg wet weight and higher were found most places both along the coast and in open sea to the south of Lofoten. To the north of Lofoten levels were lower, and there was a general increase in mercury levels from north to south and from open sea to coast, and from the North Sea coast further into the fjords. Frequent consumption of tusk caught in many areas, particularly in the southern part of Norway, may thus contribute considerably to the tolerable weekly intake for mercury. For common ling and haddock a similar pattern was found for mercury levels, although concentrations were lower than in tusk. The order of species ranged by mercury concentration in fillet was this: Blackmouth catshark > ratfish > blue ling > tusk > hake > common ling > beaked redfish > rose fish > whiting = greater forkbeard = Atlantic wolffish > cod > haddock > spotted wolffish > northern wolffish.
THE BIO-AVAILABILITY OF MERCURIC SULFIDE IN PADDY FIELD ECOSYSTEM
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Mercuric sulfide widely exists in the ore, sediment and soil of mercury mine area, which has a extremely low solubility in the nature. Its bio-availability is a focus of peoples concerning. In this study, rice was cultured in root boxes filled with paddy soil. mercuric sulfide with different polymorph and size were added, together with different species of sulfur-containing materials to investigate bio-availability of mercuric sulfide and its influence factors. ICP-MS, synchrotron radiation and molecular ecology methods were used for analyzing the content, distribution, speciation of sulfur and mercury in soil and rice samples. The results showed that the mercury content decreased from roots to stems and leaves then rice grains, and the main existence form was analogous to Hg(SG))2 in roots. With the increase of particle size of the mercuric sulfide, the content of mercury increased in brown rice. And different crystal type of mercuric sulfide was utilizated differently by rice, nano-metacinnabar was easier used than nano-cinnabar.
MERCURY AND SELENIUM CONCENTRATIONS IN SEVERAL SPECIES OF COMMERCIAL SHRIMPS IN JAPAN
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Methylmercury (MeHg) is a neurotoxicant and people are mainly exposed to MeHg through the consumption of seafood. Selenium (Se) is known to antagonize the toxicity of mercury (Hg). Therefore, both MeHg concentration and Se/Hg ratio in seafood are important factors to consider the risk of seafood consumption. The muscles of 114 commercial shrimps representing 8 species from 10 countries were obtained at supermarkets in Kumamoto and Kagoshima prefecture. We determined the concentration of total mercury (T-Hg) and MeHg in the muscle of several species of commercial shrimp using heating vaporization AAS (simple analytical method: J. Toxicol. Sci. 41, 489-500, 2016), and Se concentration using ICP-MS. The median T-Hg and MeHg in muscle of black tiger shrimp from Australia were 62.1 ng/g and 58.6 ng/g wet weight (ww) and they were higher (p<0.01) than that of shrimp from Vietnam (8.5 ng/g ww: T-Hg; 8.2 ng/g ww: MeHg) and India (10.8 ng/g ww: T-Hg; 9.1 ng/g ww: MeHg). T-Hg and MeHg of vannamei shrimps from Ecuador were 31.1 ng/g ww and 30.6 ng/g ww, and they were higher (p<0.01) than that of shrimps from India (5.3 ng/g ww: T-Hg; 5.3 ng/g ww: MeHg) and Malaysia (11.2 ng/g ww: T-Hg; 11.0 ng/g ww: MeHg). T-Hg and MeHg of white shrimp from Bangladesh were 39.1 ng/g ww and 35.4 ng/g ww, and they were higher (p<0.01) than that of shrimps from Indonesia (16.0 ng/g ww: T-Hg; 14.6 ng/g ww: MeHg). The mean of MeHg/T-Hg ratios in all species of shrimps examined in this study were in the range of 90-99%. Median of Se concentrations (ng/g ww) in the muscle of shrimps from 3 countries were 322 (Vietnam), 343 (India) and 446 (Australia) for black tiger shrimp, 219 (India), 289 (Ecuador) and 305 (Malaysia) for vanammei shrimp, 391 (India), 412 (Bangladesh) and 385 (Indonesia) for white shrimp, respectively, indicating that Se levels in the muscle of these shrimps were similar compared to variation of Hg concentration. The results indicated that T-Hg and MeHg levels in the imported and domestic commercial shrimps in Japan were lower than the Japanese regulation levels of 300 ng/g ww for MeHg for fish, and the mean of Se/T-Hg molar ratios (16-106) were comparatively high. We can conclude that the shrimps examined in this survey will not pose particularly high risk concerning MeHg exposure.
MERCURY CONTAMINATED RICE AND AIR IN ARTISANAL AND SMALL-SCALE GOLD MINING (ASGM) HOTSPOTS AND HEALTH HAZARDS TO THE IMPACTED COMMUNITIES
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Abstract not available
SCREENING OF HG LEVELS AND SPECIATION IN FISH SPECIES REPRESENTATIVE OF LOCAL CONSUMPTION FROM THE CHILEAN COAST
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Mercury pollution is considered a major environmental and public health concern. Considering its toxicity, Hg has been recently included in the top ten hazardous chemicals by the World Health Organization (1). Pregnant women and children in early life are considered the most vulnerable population to Hg harmfulness. In general, fish and seafood consumption is recognized as the most common pathway of Hg human exposure. It is especially troubling considering the recent and important increase of Hg in oceanic waters, recently reported (2).
Fishing is one of the most important industries in Chile and its commercial catch is the seventh-largest in the world. In Chile, the amount of mercury in marine species is regulated by the Food Health Regulations. It should not exceed 0.5 mg kg-1 for small fish species and for larger species, such as shark and albacore, the maximum limit is 1.5 mg kg-1 (3). However, the extent of coastal Hg levels and its concentration in fish is unknown. It is essential to establish a baseline contamination of MeHg in fish to further develop risk assessment actions in order to prevent Hg exposure via fish consumption and better inform environmental policy makers. The main aim of this work is determining the distribution and bioconcentrationof Hg in fish from the coasts of this South American country.
Representative fish species (such Merluccius gayi gayi and Genypterus chilensis) of local consumption were collected all over Chile’s long coastline. Approximatively 0.1 g of muscle was digested and Hg content was determined by CV-AFS. Speciation was carried out by isotopic dilution GC -ICP-MS. The Hg content varies between 0.1 and 4.6 mg kg -1(dry weight). The highest Hg values correspond to Graus nigra, an endemic fish species. Regarding speciation, MeHg represents more than 95% of the total Hg content, irrespective of the fish species. The Hg levels associated to the different fish species and coastal regions will be discussed. The main perspective of this study is the elucidation of Hg potential sources and its fate in the marine systems by Hg stable isotopic characterization.
References:
World Health Organization 2010
C.H. Lamborg, C.R. Hammerschmidt, K.L. Bowman, G.J. Swarr, K.M. Munson, D.C. Ohnemus, P.J. Lam, L.E Heimbürger, M.J.A. Rijkenberg, M.A. Saito. Nature 512 (7512): 65. 2014.
Reglamento Sanitario de los Alimentos (RSA- Legislación y Resoluciones del Ministerio de Salud - D.S.N°977, 2011. www.minsal.cl.
Acknowledgements: Project ECOS C15E04 and FONDECYT 1150855
SELENIUM TO MERCURY MOLAR RATIOS IN WILD FISH SPECIES FROM NORTHEASTERN ATLANTIC OCEAN: INTER- AND INTRASPECIES VARIATION
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Seafood is the main dietary source of mercury (Hg) for humans and the trade-off between beneficial nutrients and undesirable elements is still a core for many studies. Selenium (Se) and Hg interaction in seafood is a particular example of this trade-off where their co-occurrence directly affect their bioavailability and toxicity. Since 50 years ago, protective effect of Se against Hg has been addressed, and within the last 10 years, Se:Hg molar ratio has received increased attention with regards to Hg risk evaluation , particularly for saltwater fish.
In this study, we examined the concentrations of Hg and Se and the Se:Hg molar ratios in 17 teleost fish species from Barents Sea, Norwegian Sea, North Sea, Skagerrak, North Atlantic and Norwegian fjords and coastal areas. The sampling area is limited to Svalbard Islands in the north, Yuzhny Island in the east, Strait of Dover in the south and west of Iceland in the west.
The mean Se levels ranged from 0.27 to 0.78 mgkg-1 in Atlantic cod (Gadus morhua) and wolffish (Anarhichas spp.) respectively. The mean Hg levels ranged from 0.04 to 0.77 mgkg-1 with the lowest level in Atlantic mackerel (Scomber scombrus) and the highest in blue ling (Molva dipterygia), and the mean Se:Hg molar ratios varied between 1.93 in blue ling and 43.18 in Atlantic mackerel with the major contribution of Hg levels. In general pelagic species had lower Hg levels and higher Se:Hg ratio and deep water demersal species had higher Hg levels and lower Se:Hg ratios. Most species had large portion (more than 50%) of specimens with Se:Hg ratio exceeding 5 except for tusk (Brosme brosme) (4% less than 1, 53% between 1 and 5) and blue ling (19% less than 1, 80% between 1 and 5).
In general, Hg concentration showed a gradually increasing trend from north to south and the rate of accumulation with increasing size also increased gradually towards the south. Se and Hg levels showed weak positive correlation (R-square from 0.15 to 0.47) except in mackerel, pollack, herring and saithe. Se:Hg ratios were negatively correlated to the fish length and the Hg levels. For all species, Se:Hg ratios were significantly different (p <0.05) when individuals from different geographical areas were compared.
In conclusion, we can emphasize that fish from northeastern Atlantic Ocean are generally safe regarding Hg with few exceptions and Se may ameliorate the toxic effect of Hg to some extent.
HIGH CONCENTRATIONS OF MERCURY IN YELLOWFIN TUNA (THUNNUS ALBACARES) FROM THE GALÁPAGOS MARINE RESERVE AND CONTINENTAL WATERS, ECUADOR
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Yellowfin tuna (Thunnus albacares) is one of the major large pelagic fish harvested in the Southeastern Tropical Pacific and also one of the most exported and traded. The tuna fishery is both industrial and artisanal in Ecuador, being the eighth country with most metric tons of tuna caught. This species is highly consumed by the coastal population in Ecuador and the Galápagos Island, an insular region part of Ecuador’s territory. While the consumption of tuna fish is considered a source of nutrients that brings health benefits, tuna fish meat can also impose potential risks because of contamination by methylmercury. Methylmercury is a bioaccumulative and neurotoxic pollutant causing neurological and neurodevelopmental health effects in exposed people, mainly pregnant women and children, who may consume mercury-contaminated fish harvested from the sea. Very few studies have investigated mercury in large predatory fish in this equatorial region of the Pacific. The objective of this study was to assess the concentrations of total mercury (THg) in the red muscle of yellowfin tuna caught by artisanal fisheries in the Galápagos Marine Reserve and Ecuador’s mainland coast. A total of 347 tuna were sampled (243 from the Galápagos and 104 from waters offshore Ecuador’s coast). Muscle samples were analyzed using a DMA 80 mercury analyzer. 62.3 % of tuna samples exhibited size less than 70 cm. The mean concentration ± SD of mercury was 0.53 ± 0.55 μg/g (ppm) wet weight (ww). It was found that 8% of the tunas analyzed (n = 28) in this study were above the tolerable levels of Mercury established by FAO and the World Health Organization (1 ppm). The maximum concentration found was 6.8 (ppm) ww, being this one of the highest values of mercury reported for yellowfin tuna in the Pacific when compared to other studies. This study contributed with new baseline data on mercury concentrations in tuna from this region of the Pacific Ocean Basin and the initial information to establish tuna fish advisories with a limit of consumption of this species in both Ecuador and the Galapagos Islands with implications for public health in the long term.
MERCURY RISK IN POULTRY IN THE WANSHAN MERCURY MINE, CHINA
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Rice, rather than fish, has recently been identified as the major exposure pathway of mercury (Hg) to inland populations of China. In recent years, in the Wanshan Mercury Mine (WMM), SW China, local crops were used more extensively to feed poultry and the awareness of Hg pollution in crops, led to a concern over Hg contamination in poultry. In this study, total mercury (THg) and methylmercury (MeHg) burdens in muscles (leg and breast), organs (intestine, heart, stomach, liver) and blood were investigated for chickens, ducks and geese in the WMM. Elevated THg and MeHg levels, especially in livers and blood, were observed in WMM poultry. The liver may serve as a filter of blood Hg, and may be a site of MeHg demethylation. Elevated THg and MeHg burdens were observed in chickens (THg: 15.3 to 238.1 μg; MeHg: 2.2 to 15.6 μg), ducks (THg: 15.3 to 238.1 μg; MeHg: 3.5 to 14.7 μg) and geese (THg: 83.8 to 93.4 μg; MeHg: 15.4 to 29.7 μg). Organs and blood constitute more than 50% of total burdens of THg and MeHg in poultry. This study demonstrated poultry can be a new important Hg exposure source for the WMM residents, and identified a high risk of Hg exposure for the local population.
A NEW PATHWAY FOR METHYLMERCURY ACCUMULATION IN RICE PLANT: USING A STABLE ISOTOPE TRACER TECHNIQUE AND FIELD INVESTIGATION
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Methylmercury (MeHg) is a potent toxicant. Fish consumption is considered as the primary pathway of human MeHg exposure, and yet recent studies highlighted that rice is the main route of human MeHg exposure in inland areas polluted by mercury. Amounts of field investigations from mining and no-mining areas showed that rice plant, especially in grain has the highest ability for MeHg accumulation among crops. Where does this accumulation MeHg in rice plants come from, and how does it get there? So far, a consistent view think that MeHg in rice plant was originated from soil. In this study we hypothesized that air is another important pathway for MeHg accumulation in the rice plant. Stable isotope addition technique through field in-situ open top chambers(OTCs) experiments was performed to trace the uptake and translocation of gaseous organic mercury in rice plant and then quantify and assess the relative importance for assimilation of atmospheric organic Hg in rice plant. Firstly, we established a continuous low concentration DMe199Hg generation system based on the reaction of 2CH3-B12+Hg2++2H2O---(CH3)2Hg +2H2O-B12. Five levels of DMe199Hg in mixed air were set for OTCs experiments during rice growing stages. Me202Hg and Me199Hg concentration in rice tissues were determined by GC-ICPMS in rice tillering, jointing, heading, milk and mature stage. Results showed that total and tracer Me199Hg concentrations in rice tissues were statistical significance increase with the air DMe199Hg levels and the extension of growth period, which clearly reveal that rice can uptake DMeHg from air. Examining to the percentage of Me199Hg (tracer) in rice tissues to those in whole plant suggests that leaf and stem absorb large amounts of DMeHg during tillering and jointing stages, and then most of those translocated to ear of rice, and finally accumulated in the rice grain. The relative contribution percentages of tracer DMeHg to total MeHg in rice tissues calculated by model are increasing with the gaseous DMeHg concentration, and more than half of MeHg in rice leaves and about 40% to 90% of MeHg in rice grain are obtained from air with DMeHg concentrations from 16.0 to 1033.3 pg m-3. Furthermore, the preliminary investigations show that DMeHg concentration was 2 to 20 pg m-3 in surface air and 1-15pg L-1 in surface water at flooding paddy field in Wanshan mining areas, implying that the new pathway from air for MeHg accumulation in rice plant should be comprehensive evaluation at this mining areas.
SULFUR MODULATES MERCURY TRANSFORMATION AND ACCUMULATION IN RICE PLANT GROWN IN MERCURY CONTAMINATED SOILS
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Sulfur (S) is an essential element for plants and its biogeochemical cycling is strongly linked to the species of heavy metals and their transformation in soils. In this work, the effects of S (elemental sulfur and sulfate) treatment on rice growth, Hg accumulation in rice, and Hg geochemical fractions in rice rhizosphere soil were investigated. It was found that both elemental sulfur and sulfate promoted the total Hg (T-Hg) and methylmercury (MeHg) accumulation in rice grains, stalkleaf, and root but did not affect the rice growth. Sequential extraction analysis of Hg geochemical fractions in rhizosphere soil displayed increased bioavailable Hg in paddy soils. The result was further proved with Hg L3-edge X-ray absorption near-edge structure (Hg L3-edge XANES), indicating that S treatment reactivated the non-bioavailable Hg in the rhizosphere soils. This finding is significant since it suggests that the application of S fertilizers in Hg contaminated farmland can increase the accumulation of both T-Hg and MeHg in crops, which may bring much serious health problems to people depending on them. It should raise cautiousness when using sulfur-containing agents in Hg contaminated soils. On the other hand, this study also suggests that S treatment could be an effective measure to mobilize the Hg that was hard to be absorbed by plants and to accelerate the phytoremediation efficiency in Hg contaminated soils.
ELEVATED MERCURY BODY BURDEN IN PACIFIC SIDS WOMEN OF CHILDBEARING AGE
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There is little information about the body burden of mercury in Pacific Small Island Developing States (SIDS) populations, and consequently little understanding in this UN subregion about the potential adverse impacts on human health, development, intelligence and, by association, economic costs. What little data exists highlights the unusual phenomenon of high mercury levels in places where there is limited industrial pollution or coal-based power generation.
To advance the understanding of global mercury pollution impacts, IPEN undertook a study focussing on determining the methylmercury levels borne by women of childbearing age (18-44 years) in Pacific SIDS, on the basis that they represent a vulnerable sub-population. Methylmercury body burdens are particularly important for women contemplating pregnancy, because of the possible impacts of methylmercury on the developing foetus with regard to health and development endpoints.
The hypothesis for this study is that women from Pacific Islands have elevated mercury body burdens due to consumption of seafood. Members of IPENs global network coordinated with civil society partners to collect hair samples from female participants. In total, 239 hair samples from 7 Pacific SIDS were taken, analysed for mercury concentrations and compared against the 1 ppm level that approximately corresponds to the USA EPA reference dose. Preliminary results show highly-elevated mercury body burden for women in Pacific SIDS, with the most likely exposure pathway being seafood consumed as the principal dietary protein.
As methylmercury is considered an endocrine-disruptor, this may have some bearing on the rapid increase of non-communicable diseases (including diabetes and hypertension) that were deemed high priority in the outcome report from the 2014 Third International SIDS Conference.
Industrial and related sources of mercury pollution are negligible in the Pacific subregion, suggesting diffuse atmospheric mercury deposition to oceans is a key source of methylmercury contamination in seafood. While this sample size is relatively small, it illustrates a disturbing trend that may compel Pacific SIDS governments to request a broader, deeper study through the WHO. We conclude that greater efforts are needed to reduce atmospheric mercury emissions, in order to avoid contamination of fish and thus protect Pacific SIDS women and their unborn children countries from the adverse impacts of elevated methylmercury body burden.