Mercury in European Blushers,Amanita rubescens,mushrooms and topsoils: Bioconcentration potential and intake assessment

Total mercury content has been determined in fruiting bodies of European Blushers and topsoils collected from 11 sites across Poland in 2006-2008. Mercury analysis was carried out using a validated analytical method and cold-vapour atomic absorption (CV-AAS). The European Blusher effectively accumulated mercury in fruiting bodies. The mean values of total mercury in caps of European Blushers from background (uncontaminated) areas were from 0.22 to 1.0 (0.067-3.2) and in stipes from 0.16 to 0.65 (0.071-2.7) μg/g dry weight. In topsoil beneath to fruiting bodies, the median Hg concentration at 10 sites in Northern Poland varied between 0.030 and 0.072 (0.0096–0.19) μg/g dw, and in one site in Southern Poland was 0.20 (0.079–0.34) μg/g dw. Data on Hg in European Blushers from different countries were reviewed. The mean concentrations of total Hg in caps of European Blushers from two “pristine” sites in northern part of Poland were ～1.0 μg/g dw. A meal made with 300–500 g of fresh caps of European Blushers collected at such sites (assuming 90% water content in caps) can result in Hg intake of 0.0003–0.0005 mg Hg/kg bm (assuming a 60 kg bm), which is a dose equipotent to a new provisional tolerable weekly intake (PTWI) value set for inorganic Hg.     

Assessment of trace element pollution and ecological risks in a river basin impacted by mining in Colombia

Trace element pollution in rivers by anthropogenic activities is an increasing problem worldwide. In this study, the contamination and ecological risk by several trace elements were evaluated along a 100-km stretch of the San Jorge River in Colombia, impacted by different mining activities. The increase of average concentration levels and range of trace elements in sediments (in μg/g) was as follows: Cu 6656 (454–69,702) > Cd 1159 (0.061–16,227) > Zn 1064 (102–13,483) > Ni 105 (31–686) > Pb 7.2 (5.1–11.7) > As 1.8 (1.0–3.2) > Hg 0.31 (0.12–1.37). Results showed that surface sediments could be classified as very high ecological risk index (RI > 600), associated with high contamination of Hg, Cd, and Cu, in stations close mining activities. Values for pollution load index indicate an environmental deterioration (PLI > 1), and sediment quality guidelines (SQGs) suggested that Cu, Ni, Zn, and Hg caused adverse biological effects. We further used pollution indices such as contamination factor (CF), enrichment factor (EF), and geoaccumulation index (Igeo) to assess the extent of contamination. According to these indices, discharges of hazardous chemicals over many years have resulted in a high degree of pollution for Cu, Pb, and Cd, with critical values in stations receiving wastes from mining activities. Multivariate statistical analysis suggested that Hg, Cd, Cu, and Zn derived from gold and coal mining, Ni and As were related from the mining of ferronickel and coal, respectively, whereas the high Pb load was attributed to diffuse source of pollution. In sum, our study provided the first detailed database on metal concentration and ecological risks to organisms in sediments of the San Jorge River Basin, and the current results also suggested future research for public health action.

     

Distribution of Hg,As and Se in material and flue gas streams from preheater–precalciner cement kilns and vertical shaft cement kilns in China

The aim of this study was to evaluate the behavior of Hg, As, and Se in cement production. Two types of cement plants were studied, including the vertical shaft kiln (VSK) and preheater–precalciner kiln (PPK) processes. Determination of Hg, As, and Se in the main material and gas streams were performed. It was found that recycling of particulate matter captured by an air pollution control device caused a significant enrichment of Hg and As inside both processes. The total quantity of Hg entering the process and the quantity emitted to the atmosphere were found to be 10–109 and 6.3–38 mg, respectively, per ton of clinker produced. The average Hg emission was calculated to be around 41% of the total mercury input. The emissions found complied with the European Union (EU) limit and exceeded partly the U.S. limit. Furthermore, it was found that oxidized mercury was the dominant species in the PPK process, whereas the reduced form was dominant in the VSK process, due to the oxidizing and reducing gas conditions, respectively. Regarding the distribution of As and Se, the major amounts were bound to the solid materials, that is, cement clinker and particulate matter. Based on cement production data in China in 2013, the annual emissions of Hg and As were estimated to be in the range of 8.6–52 and 4.1–9.5 tons, respectively.

Implications: There are fairly limited studies on Hg, As, and Se measurements from cement manufacturing facilities in China, and even more limited studies on the behavior in vertical shaft kilns. The needs for increased emission reduction efforts in energy-intensive industries are globally recognized, and an improved understanding of the processes ongoing in a cement kilns system is decisive. Since the processes are complex and almost impossible to recreate in the laboratory, field measurements are indeed important. The findings in the present study were solely based on field measurements and the data are considered to be valuable for the further development of emission reduction technology.     

Mercury, cadmium, lead and selenium in ringed seals (Phoca hispida) from the Baltic Sea and from Svalbard

The concentrations of mercury (Hg), cadmium (Cd), lead (Pb) and selenium (Se) were determined in liver, kidney and muscle samples from 20 Baltic ringed seals (Phoca hispida botnica) (3-32 years), and from 17 ringed seals (Phoca hispida) (0-20 years) from Svalbard, in the Arctic. The concentrations of Hg and Se were considerably higher in the Baltic ringed seals, but the Cd concentrations lower than in the Svalbard ringed seals. There was no big geographical difference with respect to Pb concentrations. Se and Hg concentrations showed a significant positive correlation in both regions. By comparison with earlier studies on Baltic seals, the metal concentrations have remained at the same level since the 1980s. Of the metals we studied, only the level of Hg in Baltic ringed seals can be considered high (mean 53 mg/kg, range 6.5-124 mg/kg wet wt. for liver), but probably not high enough to cause metal intoxication. No pathological changes associated with metal intoxication were observed in the seals.     

Mercury in the traditional diet of indigenous peoples in Canada

Traditional food of indigenous people in Canada, particularly fish and marine mammal meat, has mercury (Hg) concentrations exceeding the Canadian consumption guideline level of 0.5 microg/g. Health effects of Hg in traditional food are, therefore, a concern. We conducted contaminant exposure assessments in 28 indigenous communities in Canada. Hg exposure was greatest among communities with high use of marine mammals as food. Exposure among other communities was variable. Recent adoption of a lower intake guideline for women of reproductive age and by Health Canada may decrease the use of traditional food, and could result in other health problems, such as increased risk of diabetes and cardiovascular disease.     

Triclosan in Fresh Water Fish Gibelion Catla from the Kaveri River,India, and Its Consumption Risk Assessment

Triclosan is a common antimicrobial agent that is found in significant levels in the aquatic environment and may elicit effects on aquatic organisms through unexpected modes of action. In this study, triclosan was quantified in fish from the Kaveri River, India, by using the gas chromatography and mass spectrometry technique and it was found in the range of 0.73–50 ng/g wet weight (ww). The mean bioaccumulation factor based on water (BAF_w 820) and sediment (BAF_s 2.12) in the Kaveri River showed that triclosan is accumulative in fish, and reflects its feeding behavior. The bioaccumulation indicates triclosan's persistence or prevalence throughout the river stretch. Human risk assessment through dietary intake demonstrated that the triclosan exposure is five orders of magnitude lower than the acceptable daily intake (50 μg/kg bw) and US EPA reference dose (300 μg/kg bw/day). This investigation is the first to report the bioaccumulation of triclosan in freshwater fish from India. Further, the results indicate that this fish acts as a biomarker of exposure for triclosan and thus shall be used to report triclosan pollution in the future.     

Specific accumulation of mercury and selenium in seabirds

Total mercury (T-Hg), methyl mercury (MeHg) and selenium (Se) concentrations were determined to elucidate the relationship between Hg and Se levels in the liver of 10 seabird species. Highest concentrations of T-Hg (mean 267 microg/g dry wt), MeHg (mean 25.5 microg/g dry wt) and Se (mean 113 microg/g dry wt) were in the liver of black-footed albatross (Diomedea nigripes). An equivalent molar ratio of 1:1 between T-Hg and Se was found in the liver of individuals which contain over 100 microg Hg/g. However, such a relationship was unclear in other individuals which had relatively low Hg levels. This suggests that Se plays a role in Hg detoxification for those individuals with high Hg. In seabird tissues, Hg and Se levels should be a most important factor determining the relationship between Hg and Se, and fluctuation of Hg burden through molting and the species-specific demethylation capacity would also influence their relationships.     

Trace element (Cd, Cu, Hg, Se, Zn) accumulation and tissue distribution in loggerhead turtles (Caretta caretta) from the Western Mediterranean Sea (southern Italy)

Cadmium (Cd), copper (Cu), mercury (Hg), selenium (Se) and zinc (Zn) were determined in the liver, kidney and muscle of 29 loggerhead turtles, Caretta caretta, from the South Tyrrhenian Sea (Western Mediterranean). No significant differences (p>0.05) were detected between males and females. Trace element concentrations were not influenced by the size of the specimen except Se in the liver, which was negatively correlated with the curved carapace length (p<0.001). Muscles generally displayed the lowest trace element burdens, with the exception of Zn which contained concentrations as high as 176 microgg-1dwt. Kidneys displayed the highest Cd and Se mean concentrations (57.2+/-34.6 and 15.5+/-9.1 microgg-1dwt, respectively), while liver exhibited the highest Cu and Hg levels (37.3+/-8.7 and 1.1+/-1.7 microgg-1dwt, respectively). Whichever tissue is considered, the toxic elements had elevated coefficients of variation (i.e. from 60% to 177%) compared to those of the essential ones (i.e. from 14% to 65%), which is a consequence of homeostatic processes for Cu, Se and Zn. Globally, the concentrations of Hg remained low in all the considered tissues, possibly the result of low trophic level in sea turtles. In contrast, the diet of loggerhead turtles would result in a significant exposure to Cd. Highly significant correlations between Cd and Cu and Zn in the liver and kidney suggest that efficient detoxification processes involving MT occur which prevent Cd toxicity in loggerhead turtles.     

Mercury in European Blushers, Amanita rubescens, mushrooms and topsoils: bioconcentration potential and intake assessment

Total mercury content has been determined in fruiting bodies of European Blushers and topsoils collected from 11 sites across Poland in 2006-2008. Mercury analysis was carried out using a validated analytical method and cold-vapour atomic absorption (CV-AAS). The European Blusher effectively accumulated mercury in fruiting bodies. The mean values of total mercury in caps of European Blushers from background (uncontaminated) areas were from 0.22 to 1.0 (0.067-3.2) and in stipes from 0.16 to 0.65 (0.071-2.7) μg/g dry weight. In topsoil beneath to fruiting bodies, the median Hg concentration at 10 sites in Northern Poland varied between 0.030 and 0.072 (0.0096-0.19) μg/g dw, and in one site in Southern Poland was 0.20 (0.079-0.34) μg/g dw. Data on Hg in European Blushers from different countries were reviewed. The mean concentrations of total Hg in caps of European Blushers from two "pristine" sites in northern part of Poland were ～1.0 μg/g dw. A meal made with 300-500 g of fresh caps of European Blushers collected at such sites (assuming 90% water content in caps) can result in Hg intake of 0.0003-0.0005 mg Hg/kg bm (assuming a 60 kg bm), which is a dose equipotent to a new provisional tolerable weekly intake (PTWI) value set for inorganic Hg.     

Exposure to heavy metals and infectious disease mortality in harbour porpoises from England and Wales

We investigate whether long-term exposure to heavy metals, including immunosuppressive metals like mercury (Hg), is associated with infectious disease in a wild cetacean. Post-mortem investigations on 86 harbour porpoises, Phocoena phocoena, found dead along the coasts of England and Wales revealed that 49 of the porpoises were healthy when they died as a consequence of physical trauma (most frequently entrapment in fishing gear). In contrast, 37 porpoises died of infectious diseases caused by parasitic, bacterial, fungal and viral pathogens (most frequently pneumonia caused by lungworm and bacterial infections). We found that mean liver concentrations of Hg, selenium (Se), the Hg:Se molar ratio, and zinc (Zn) were significantly higher in the propoises that died of infectious disease compared to healthy porpoises that died from physical trauma. Liver concentrations of lead (Pb), cadmium (Cd), copper (Cu) and chromium (Cr) did not differ between the two groups. Hg, Se, and the Hg:Se molar ratio were also positively correlated with age. The association between Zn concentration and disease status may result from Zn redistribution in response to infection. Further work is required to evaluate whether chronic exposure to Hg may have presented a toxic challenge to the porpoises that succumbed to infectious disease.     

Effects of environmental methylmercury on the health of wild birds, mammals, and fish

Wild piscivorous fish, mammals, and birds may be at risk for elevated dietary methylmercury intake and toxicity. In controlled feeding studies, the consumption of diets that contained Hg (as methylmercury) at environmentally realistic concentrations resulted in a range of toxic effects in fish, birds, and mammals, including behavioral, neurochemical, hormonal, and reproductive changes. Limited field-based studies, especially with certain wild piscivorous bird species, e.g., the common loon, corroborated laboratory-based results, demonstrating significant relations between methylmercury exposure and various indicators of methylmercury toxicity, including reproductive impairment. Potential population effects in fish and wildlife resulting from dietary methylmercury exposure are expected to vary as a function of species life history, as well as regional differences in fish-Hg concentrations, which, in turn, are influenced by differences in Hg deposition and environmental methylation rates. However, population modeling suggests that reductions in Hg emissions could have substantial benefits for some common loon populations that are currently experiencing elevated methylmercury exposure. Predicted benefits would be mediated primarily through improved hatching success and development of hatchlings to maturity as Hg concentrations in prey fish decline. Other piscivorous species may also benefit from decreased Hg exposure but have not been as extensively studied as the common loon.     

Atmospheric emissions of F,As, Se,Hg, and Sb from coal-fired power and heat generation in China

Coal is one of the major energy resources in China, with nearly half of produced Chinese coal used for power and heat generation. The large use of coal for power and heat generation in China may result in significant atmospheric emissions of toxic volatile trace elements (i.e. F, As, Se, Hg, and Sb). For the purpose of estimating the atmospheric emissions from coal-fired power and heat generation in China, a simple method based on coal consumption, concentration and emission factor of trace element was adopted to calculate the gaseous emissions of elements F, As, Se, Hg, and Sb. Results indicate that about 162 161, 236, 637, 172, and 33 t F, As, Se, Hg, and Sb, respectively, were introduced into atmosphere from coal combustion by power and heat generation in China in 2009. The atmospheric emissions of F, As, Se, Hg, and Sb by power and heat generation increased from 2005 to 2009 with increasing coal consumptions.     

Trace elements in striped dolphins (Stenella coeruleoalba) from the western Mediterranean

Tissues obtained from Stenella coeruleoalba stranded along the Spanish and Italian Mediterranean coasts from 1987 to 1994 were analysed for cadmium (Cd), copper (Cu), mercury (Hg), selenium (Se) and zinc (Zn). The age, length and weight of the dolphins were recorded. Hg levels were also assayed in skin biopsies from dolphins of the same species in the waters off northeastern Spain and in the Tyrrhenian and Ligurian Seas. Levels of all elements differed in muscle of stranded dolphins from the two areas. Hg was higher in tissues from animals stranded on the Italian coasts and in skin biopsies obtained in the Tyrrhenian and Ligurian Seas, than in the respective Spanish samples. This is probably related to Hg pollution from the natural weathering of cinnabar ores in central Italy. Se and Cd levels had similar accumulation patterns to those of Hg. Accumulation of Hg and Se is explained by the existence of a detoxification pathway involving both elements, however the reason for the similar Cd trend is unclear. Geographical differences in the accumulation pattern of these elements may reflect the existence of two different populations of Stenella coeruleoalba in the western Mediterranean.     

Mercury in hair and blood from residents of Phnom Penh (Cambodia) and possible effect on serum hormone levels

High concentration of mercury (Hg) in hair has been reported for Cambodians. To confirm the Hg contamination occurring through intake, Hg concentrations were determined in both hair and blood of residents (n=20) from Phnom Penh, Cambodia. Mercury concentrations in the hair and blood were 0.69-190microg g(-1) dry wt and 5.2-58microg l(-1), respectively, which were lower than those from Hg contaminated or high fish intake regions, but were higher than those from non-contaminated regions. Some female subjects had hair and blood Hg levels exceeding the threshold values for neurotoxic effects. Interestingly, serum estrone and estradiol levels were positively correlated with blood Hg level for both males and females, indicating possible induction of female hormones by Hg exposure in Cambodians.     

Mercury species accumulation and trophic transfer in biological systems using the Almadén mining district (Ciudad Real,Spain) as a case of study

The impact of mercury (Hg) pollution in the terrestrial environments and the terrestrial food chains including the impact on human food consumption is still greatly under-investigated. In particular, studies including Hg speciation and detoxification strategies in terrestrial animals are almost non-existing, but these are key information with important implications for human beings. Therefore, in this work, we report on Hg species (inorganic mercury, iHg, and monomethylmercury, MeHg) distribution among terrestrial animal tissues obtained from a real-world Hg exposure scenario (Almadén mining district, Spain). Thus, we studied Hg species (iHg and MeHg) and total selenium (Se) content in liver and kidney of red deer (Cervus elaphus; n?=?41) and wild boar (Sus scrofa; n?=?16). Similar mercury species distribution was found for both red deer and wild boar. Major differences were found between tissues; thus, in kidney, iHg was clearly the predominant species (more than 81 %), while in liver, the species distribution was less homogeneous with a percentage of MeHg up to 46 % in some cases. Therefore, Hg accumulation and MeHg transfer were evident in terrestrial ecosystems. The interaction between total Se and Hg species has been evaluated by tissue and by animal species. Similar relationships were found in kidney for both Hg species in red deer and wild boar. However, in liver, there were differences between animals. The possible underlying mechanisms are discussed.     

Influence of mercury and selenium chemistries on the progression of cardiomyopathy in pygmy sperm whales, Kogia breviceps

More than half of pygmy sperm whales (Kogia breviceps) that strand exhibit signs of cardiomyopathy (CMP). Many factors may contribute to the development of idiopathic CMP in K. breviceps, including genetics, infectious agents, contaminants, biotoxins, and dietary intake (e.g. selenium, mercury, and pro-oxidants). This study assessed trace elements in K. breviceps at various stages of CMP progression using fresh frozen liver and heart samples collected from individuals that stranded along US Atlantic and Gulf coasts between 1993 and 2007. Standard addition calibration and collision cell inductively coupled plasma mass spectrometry (ICP-MS) were employed for total Se analysis and pyrolysis atomic absorption (AA) was utilized for total Hg analysis to examine if the Se/Hg detoxification pathway inhibits the bioavailability of Se. Double spike speciated isotope dilution gas chromatography ICP-MS was utilized to measure methyl Hg and inorganic Hg. Immunoblot detection and colorimetric assays were used to assess protein oxidation status. Data collected on trace elements, selenoproteins, and oxidative status were evaluated in the context of animal life history and other complementary histological information to gain insight into the biochemical pathways contributing to the development of CMP in K. breviceps. Cardiomyopathy was only observed in adult pygmy sperm whales, predominantly in male animals. Both Hg:Se molar ratios and overall protein oxidation were greater in males than females and increased with progression of CMP.     

Environmental mercury contamination of an artisanal zinc smelting area in Weining County, Guizhou, China

To investigate the extent of Hg contamination due to artisanal Zn smelting activities in Weining County, northwestern Guizhou, China, total Hg and methyl mercury (MeHg) concentrations in soil and surface water were determined. Samples of corn plants growing in the study area were also collected for total Hg analysis. A high geometric mean Hg emission factor of 75gHgt(-1)Zn was estimated and significantly elevated total gaseous mercury (TGM) concentrations were found in the atmosphere adjacent to the Zn smelting sites, ranging from 30 to 3814ngm(-3). Total Hg and MeHg concentrations in topsoil samples ranged from 62 to 355microgkg(-1) and from 0.20 to 1.1microgkg(-1), respectively. Total Hg Concentrations in corn plant tissues increased in the order of grains相似文献   

Health risks of environmental exposure to metals and herbicides in the Pardo River,Brazil

Mixture of metals and herbicides in rivers may pose relevant risks for the health of surrounding communities. Humans may be exposed to river pollution through intake of contaminated water and fish, as well as irrigated agricultural products. The aim of this study was to assess the human health risks of environmental exposure to metals and herbicides through water and fish intake in the Pardo River. Metals (Al, As, Be, Cd, Cr, Cu, Pb, Mn, Hg, Ni, Tl, Sn, V, and Zn) were analyzed in river water and in edible fish. Herbicides (ametryn, atrazine, diuron, hexazinone, simazine, and tebuthiuron) were analyzed in river water. Seasonal variances were also studied. Aluminum, Cd, Cu, Mn, Pb, and Zn levels in river water were higher than the USEPA benchmarks. Non-carcinogenic risks due to pollutants mixture exposure were above the limit, and carcinogenic risks of As exposure were >10^?6 in the sampling points during the rainy season. Metal levels in fish were lower than the Brazilian legislation and do not pose a threat to public health. Herbicides were detected in four sampling points, with atrazine concentrations (range 0.16–0.32 μg/L) below the Brazilian standard (2.0 μg/L), but above the European Union standard (0.1 μg/L). Considering the water supply needs of cities located in the Pardo River Basin and the persistence of metals and herbicides, the present study indicated that there was a seasonal influence on non-carcinogenic and carcinogenic risks to human health, especially in the rainy season. Studies for water treatment plants implantation should consider the risks of exposure to persistent substances, in order to protect the population.     

Influences of salinity on the biokinetics of Cd, Se, and Zn in the intertidal mudskipper Periophthalmus cantonensis

The biokinetics (aqueous uptake, dietary assimilation, and elimination) of Cd, Se, and Zn in the intertidal mudskipper, Periophthalmus cantonensis, were examined at different acclimated salinities using the radiotracer technique. The dietary assimilation efficiency from ingested radiolabeled polychaetes was the highest for Se (32–40%), followed by Zn (5–7%) and Cd (2–3%), and was not influenced by salinity within a range of 10–30 psu. Uptake from the dissolved phase typically exhibited a linear pattern within the first 12 h of exposure, followed by a second slower uptake. The highest concentration factor (CF) was found for Zn, followed by Cd and Se. Differences in salinity did not significantly affect the CF of the three metals within the first 12 h, but the CFs were significantly higher at lower salinities (10–20 psu) than at the highest salinity (30 psu) by the end of 48 h exposure. Because the degrees to which the uptake of Se (a metalloid) and Cd/Zn were affected by salinity were comparable, we concluded that metal speciation as a result of salinity change was not important in leading to a change in metal CF. Physiological changes may be responsible for the increasing uptake at lowered salinity. The elimination rates of the three metals (0.01–0.06 d⁻¹) were not significantly affected by salinity, but Se was eliminated at a faster rate following aqueous uptake than following dietary ingestion. There was no consistent influence of exposure routes on Cd and Zn elimination. The accumulated Cd was mainly associated with the gut, whereas the muscle was the dominant target site for Se and Zn accumulation.     

Distributions and determinants of mercury concentrations in toenails among American young adults: the CARDIA Trace Element Study

Since data on mercury (Hg) levels in Caucasians and African Americans (AAs) of both genders are lacking, this study aims to present toenail Hg distributions and explore the potential determinants using data from the Coronary Artery Risk Development in Young Adults Trace Element Study. Data from 4,344 Americans, aged 20–32 in 1987, recruited from Oakland, Chicago, Minneapolis, and Birmingham were used to measure toenail Hg levels by instrumental neutron-activation method. The Hg distribution was described with selected percentiles and geometric means. Multivariable linear regression (MLR) was used to examine potential determinants of Hg levels within ethnicity–gender subgroups. The geometric mean of toenail Hg was 0.212 (95 % CI?=?0.207–0.218)?μg/g. Hg levels varied geographically with Oakland the highest [0.381 (0.367–0.395) μg/g] and Minneapolis the lowest [0.140 (0.134–0.147) μg/g]. MLR analyses showed that male gender and AA ethnicity were negatively associated with toenail Hg levels, and that age, living in Oakland city, education level, alcohol consumption, and total fish intake were positively associated with toenail Hg concentrations within each ethnicity–gender subgroup. Current smokers were found to have higher Hg only in AA men. This study suggested age, gender, ethnicity, study center, alcohol, education level, and fish consumption consistently predict toenail Hg levels. As fish consumption was the key determinant, avoiding certain types of fish that have relatively high Hg levels may be crucial in reducing Hg intake.