Mercury Contamination In Fish Research Articles

Risk Assessment of Mercury-Contaminated Fish Consumption in the Brazilian Amazon: An Ecological Study.

Mercury is one of the most dangerous contaminants on the planet. In recent years, evidence of mercury contamination in the Amazon has significantly increased, notably due to gold-mining activities. Although mercury contamination in fish has consistently been documented, little is known about the risk associated with fish consumption by populations in urban areas of the Amazon. We sampled 1010 fish sold in public markets in six state capitals and 11 additional cities. Mercury levels were determined for each specimen, and the evaluation of the health risks associated with consuming mercury-contaminated fish was conducted according to the methodology proposed by the World Health Organization (WHO). Our study reveals that more than one-fifth (21.3%) of the fish sold in urban centers had mercury levels above the safe limits (≥0.5 µg/g) established by the Brazilian Health Surveillance Agency (ANVISA). The prevalence of Hg contamination ≥0.5 µg/g was approximately 14 times higher in carnivorous than in noncarnivorous fish. The analysis of the risk attributable to fish consumption reveals that daily mercury intake exceeded the reference dose recommended by the U.S. EPA in all population groups analyzed, reaching up to 7 and 31 times in women of childbearing age and children from 2 to 4 years old, respectively. However, these risks are diverse depending on the type of fish consumed and must be considered to formulate appropriate nutritional guidelines for safe fish consumption by the local community.

Education on mercury exposure from fish and its processed products among school children in the Kenjeran Beach Area, Surabaya

Introduction. Fish is a protein source that can be easily found especially in Indonesia, a maritime country. However, the development of industrialization also contributes to increased pollution. In some cases, industrial wastewater contains metals that can be toxic for fish and their processed products. Mercury is one of the heavy metals that is commonly found in fish and has been found to have negative impacts on the health of the human body especially on kids. Objective. The purpose of this study is to increase schoolchildren's knowledge of the risks of mercury exposure from fish and their products. Methods. A quasi-experimental pre-post-test design was conducted among 120 elementary school students in SDN Sukolilo 250 and SDN Komplek Kenjeran II. The sampling method was done using simple random sampling. Elementary school students were divided into two groups. The intervention group received information about the dangers of mercury contamination in fish and its products and the control group received general education about the behavior of a clean and healthy lifestyle. Results. From the test, we found that the result of the paired sample t-test is <0.001 and the delta of mean score between pre-test and post-test among the intervention group was higher than the control group. Conclusion. Nutrition education in elementary students may influence the nutritional behavior of food consumption and mercury awareness. Nutrition education had a positive effect on individual behavior by increasing knowledge, behavioral intentions, and perceived behavioral control.

Mercury Contamination in Fish and Its Effects on the Health of Pregnant Women and Their Fetuses, and Guidance for Fish Consumption—A Narrative Review

As a principal source of long-chain omega-3 fatty acids (3FAs), which provide vital health benefits, fish consumption also comes with the additional benefit of being rich in diverse nutrients (e.g., vitamins and selenium, high in proteins and low in saturated fats, etc.). The consumption of fish and other seafood products has been significantly promoted universally, given that fish is an important part of a healthy diet. However, many documents indicate that fish may also be a potential source of exposure to chemical pollutants, especially mercury (Hg) (one of the top ten chemicals or groups of chemicals of concern worldwide), and this is a grave concern for many consumers, especially pregnant women, as this could affect their fetuses. In this review, the definition of Hg and its forms and mode of entrance into fish are introduced in detail and, moreover, the bio-accumulation of Hg in fish and its toxicity and action mechanisms on fish and humans, especially considering the health of pregnant women and their fetuses after the daily intake of fish, are also reviewed. Finally, some feasible and constructive suggestions and guidelines are recommended for the specific group of pregnant women for the consumption of balanced and appropriate fish diets in a rational manner.

Mercury Contamination of Fish and Their Prey Across a Riverine Food Web

Lakes and reservoirs are frequently monitored by researchers for elevated mercury concentrations in sportfish. Rivers and streams, especially those of smaller orders, are less frequently monitored for mercury contamination and nonsport fishes and invertebrates, although important components of the food web, are rarely examined. We addressed this gap by surveying mercury levels in a stream community in the Kiamichi River in southeastern Oklahoma, U.S., by sampling fish and macroinvertebrates at ten sites in the river. We found elevated levels of mercury across taxa within the river including individuals of smallmouth bass populations 10–25 cm in length having concentrations (2986 ± 1053 ng/g dry weight) above the U.S. Environmental Protection Agency human limit. Furthermore, we observed high concentrations in darters and logperch (1133 ± 464 ng/g dry weight), nonsport fishes found predominantly in rivers and streams. Our results indicate mercury contamination can reach elevated concentrations in rivers and stream food webs, posing risks to both humans and wildlife.

Mercury Contamination on Aquatic Organisms in related to Artisanal Small-scale Gold Mining Activity in Indonesia: A Mini Review

Artisanal Small Scale Gold Mining (ASGM) is the largest source of Hg pollution in the environment. Indonesia has ratified the Minamata convention in 2013. Mercury pollution to the aquatic environment is a great concern due to its potential impact may threat the aquatic ecosystem. In this study we conduct a mini literature review dealing with the impact of mercury pollution on aquatic organisms in Indonesia, this study provides an overview of mercury contamination in fish and macroinvertebrates in Indonesia which is related to ASGM activities, based on peer-reviewed literature recorded in the Scopus database (www.scopus.com). Keywords mercury OR Hg AND ASGM AND Indonesia was used to retrieve literatures from the database. The identified articles were screened for relevance at the title, abstract, and full text level using predefined inclusion criteria. The mercury accumulation in freshwater fish and macroinvertebrates were ranged from 0.005 mg/kg to 19 mg/kg, and from 0.002 mg/kg to 1,46 mg/kg, respectively. While mercury accumulation in in marine fish and macroinvertebrates were from 0,014 mg/kg to 57 mg/kg and 0.002 mg/kg to 2.99 mg/kg, respectively. The highest mercury accumulation in freshwater fish was found in Manado, North Sulawesi and the lowest was in Talawaan Watershed, North Sulawesi, while in Marine fish, the highest Hg accumulation was also found in Manado, North Sulawesi, and the lowest accumulation was found in Buyat, North Sulawesi. Introduction

Mercury in Dried Market Fish of Hong Kong and San Francisco: Human Health Implications

Asian, Asian Pacific Islanders, and Asian American residents of San Francisco have higher exposure to mercury and the associated health risks associated with methylmercury toxicity from fish consumption than other demographics across the United States. Due to their higher annual fish consumption, Hong Kong Chinese residents have elevated risks to methylmercury exposure. Objectives: We investigate samples of dried market fish from San Francisco and from Hong Kong as potential sources of mercury contamination in fish commonly consumed by Asian and Asian American residents. Methods: We analyze 81 samples of dried market fish from San Francisco and Hong Kong for mercury concentration using Inductively Coupled Plasma Emission Spectrograph and Processing Cold Vapor Atomic Fluorescence Spectrometry. We binned into market categories, trophic level, and habitat type for statistical analysis. Results: No significant difference was observed in the mercury levels of samples between San Francisco and Hong Kong (p-value = 0.47). Dried samples did show higher rates of mercury than wet samples reported by the FDA. Data from dried market fish samples also show evidence of bioaccumulation: the concentration of toxins in higher trophic levels of fish (p-value < 0.01). Eliminating apex predators, nearly all samples of fish from both locations and from lower trophic levels had levels below the lowest health advisory thresholds of 0.5 ppm methylmercury by weight. Discussion: Dried fish samples from markets in San Francisco and Hong Kong showed mercury levels with the potential to exceed guidelines set by the EPA and the EFSA, but consumption rates are lacking to know if this threshold is actually being exceeded by consumers. We make recommendations regarding the health risks of dried market fish and of consuming or avoiding fish from certain trophic groups.

Fish Sellers Knowledge on Exposure of Mercury from Fish in the Kenjeran Beach Area, Surabaya

The development in industrialization and human activities causing public health problems related to the safety of fish consumed in areas where industrialization is taking place especially in Surabaya city. One of the concerns on food safety especially in fish is the contamination of mercury. This study aimed to measure and identify the mercury contamination in fish especially in freshwater and saltwater fish and to assess the mercury contamination knowledge level among fish sellers in Kenjeran Beach area, Surabaya. A number of 36 sellers from eight traditional markets located near Kenjeran Beach area were randomly selected and 72 fish were taken to the laboratory to assess the mercury concentration. The sellers were given a questionnaire to assess their knowledge of mercury pollution in fish. The result showed that 55.5% of saltwater fish were contaminated with mercury (mean=0.00686 ppm). The mean score of questionnaires was 7.69 out of 19. There was no significant association between the questionnaire score and fish’s mercury concentration. This study highlights the association between sellers buying fish from Kenjeran Beach and fish’s mercury contamination. The increased risk of contamination from food can occur due to the low awareness among citizens and food sellers. Therefore, direct and indirect strategies to empower people who live near Kenjeran Beach Area to choose low mercury concentrated fish are needed.

Education on Mercury Exposure from Fish and its Product in Elementary Students in Kenjeran Beach Area, Surabaya: A Study Protocol

Fish is one of the high protein food sources that could be found easily in Indonesia. recent trends in industrialization and human activity (e.g., agriculture) that started the degradation of environmental quality such as mercury contamination in fish. This problem has become a concern because the incident occurs more frequently and could affect the health condition both in the long and short term. A quasi-experimental study will be conducted at public school located in Kenjeran District, Surabaya. The framework of Health Behavior Model theory is used to educate the students on the danger of mercury contamination in fish and its products. This study aimed to increase the student’s knowledge on the danger of mercury contamination in fish and its products. This study targets elementary school children with total 135 students. The Universal Trial Number (UTN) of this study is U1111-1269-3728. This study also has been approved by the TCTR Committee with identification number TCTR20210913003.

Influence of Macrophyte and Gut Microbiota on Mercury Contamination in Fish: A Microcosms Study

The freshwater lakes of southwestern France are subject to the development of invasive macrophytes which are associated with mercury (Hg) contamination of the food web. The aim of this study was to determine the bioavailability of methylmercury (MeHg) produced by plant roots in aquatic ecosystems. A microcosm experiment was performed using isotopically enriched inorganic Hg at environmental concentrations (1 µg 199IHg·L−1). For all conditions, total Hg in fish as well as Hg species associated with different compartments (water, sediments, plant roots, fish) were analyzed by gas chromatography-inductively coupled plasma-mass spectrometry (GC-ICP-MS). In addition, sediment, plants, and fish gut microbiota were studied by MiSEQ sequencing. Some strains were isolated and tested for their ability to methylate Hg. The results revealed 199MeHg production in plant roots and the presence of this form in fish (tissues and gut), highlighting a MeHg trophic transfer. Moreover, methylator bacteria were identified from the gut contents of the fish when they were in the presence of plants. Some of them were related to bacteria found in the plant roots. On the basis of these results, the transfer of MeHg and bacteria from plants to fish is highlighted; in addition, Hg methylation is strongly suspected in the fish gut, potentially increasing the Hg bioaccumulation.

MERCURY EXPOSURE FROM FISH IN THE KENJERAN BEACH AREA, SURABAYA: RESEARCH PROTOCOL

Background: One of the abundant food sources of high protein is fish. Fish can be an alternative source of protein. However, recent developments in industrialization and human activities (agriculture, plantations) that lead to degradation of environmental quality followed by ecological imbalances have created major public health problems related to the safety of fish consumed in mining areas and industrialization has occurred. Methods: This study was conducted by analyzing mercury levels in raw fish (freshwater and saltwater fish) originating from the waters of the city of Surabaya. The samples used were the total population of 8 traditional markets at Kenjeran Beach in Surabaya. Fish seller recruitment was carried out using a simple random sampling technique. Seven sellers were randomly selected from each market. From each seller, one freshwater fish, and one saltwater fish was taken for laboratory analysis of mercury contamination. The fish seller's knowledge was assessed through an interview with a structured questionnaire. Discussion: The purpose of this study was to measure and identify mercury contamination in fish (freshwater and saltwater fish) and to see the level of knowledge of fish sellers regarding mercury contamination in fish. Due to the different levels of knowledge for each seller. Potentially, this research can provide information and education to sellers regarding mercury contamination and obtain a map of the distribution of mercury pollution in the waters of the Kenjeran area of Surabaya.

Parametric Inference Using Nomination Sampling with an Application to Mercury Contamination in Fish

Randomized nomination sampling (RNS) is a rank-based sampling technique which has been shown to be effective in several nonparametric studies involving environmental, agricultural, medical and ecological applications. In this paper, we investigate parametric inference using RNS design for estimating an unknown vector of parameters θ in some parametric families of distributions. We examine both maximum likelihood (ML) and method of moments (MM) approaches. We introduce four types of RNS-based data as well as necessary EM algorithms for the ML estimation under each data type, and evaluate the performance of corresponding estimators in estimating θ compared with those based on simple random sampling (SRS). Our results can address many parametric inference problems in reliability theory, sport analytics, fisheries, etc. Theoretical results are augmented with numerical evaluations, where we also study inference based on imperfect ranking. We apply our methods to a real data problem in order to study the distribution of the mercury contamination in fish body using RNS designs.

Risk perception and specific behaviors of anglers concerning mercury contamination of fish

In recent years, mercury levels in some predatory fishes of several lakes of South-West France, exceeding the European Union nutritional recommendations threshold for safe consumption have been noticed. This led to a decision by regional authorities to ban consumption of those species. We conducted a questionnaire-based study on 276 users of four lakes of the region, two of which were affected by the ban, in order to better understand how it had affected perception of the risk and the associated behaviors. Our study revealed that anglers were the major fish consumers. It also showed that the ban had a poor impact on anglers’ actual fish consumption, despite their being globally well informed about its existence. We conclude that the ban has had a weak impact on anglers’ perception of risk, and that safety nutrition policies should better take into account this factor in the future.

The potential impact of new Andean dams on Amazon fluvial ecosystems.

Increased energy demand has led to plans for building many new dams in the western Amazon, mostly in the Andean region. Historical data and mechanistic scenarios are used to examine potential impacts above and below six of the largest dams planned for the region, including reductions in downstream sediment and nutrient supplies, changes in downstream flood pulse, changes in upstream and downstream fish yields, reservoir siltation, greenhouse gas emissions and mercury contamination. Together, these six dams are predicted to reduce the supply of sediments, phosphorus and nitrogen from the Andean region by 69, 67 and 57% and to the entire Amazon basin by 64, 51 and 23%, respectively. These large reductions in sediment and nutrient supplies will have major impacts on channel geomorphology, floodplain fertility and aquatic productivity. These effects will be greatest near the dams and extend to the lowland floodplains. Attenuation of the downstream flood pulse is expected to alter the survival, phenology and growth of floodplain vegetation and reduce fish yields below the dams. Reservoir filling times due to siltation are predicted to vary from 106–6240 years, affecting the storage performance of some dams. Total CO2 equivalent carbon emission from 4 Andean dams was expected to average 10 Tg y-1 during the first 30 years of operation, resulting in a MegaWatt weighted Carbon Emission Factor of 0.139 tons C MWhr-1. Mercury contamination in fish and local human populations is expected to increase both above and below the dams creating significant health risks. Reservoir fish yields will compensate some downstream losses, but increased mercury contamination could offset these benefits.

Fisheries, fish pollution and biodiversity: choice experiments with fishermen, traders and consumers

The increasing rates of per capita consumption of fish around the world should be a matter of concern for those interested in the threats to fishing stocks, aquatic biodiversity and human health. Fish consumption has positive health benefits but also brings higher risks of intake of heavy metals for humans. This increase in the demand for fish products has also been accompanied with fishing practices that threaten biodiversity. This article aims at evaluating from an economic perspective how important are these health and biodiversity components for those in the fish value chain, from fishermen to final consumers, using an experimental approach to estimate, through conjoint valuation techniques, the economic value of these aspects in the decision making of these agents. We find that final consumers place a significant economic value to the reduction of exposure to mercury contamination in fish; we also show that consumers respond positively to an education campaign showing the effects of mercury contained in fish, and that this money value could be used to create campaigns that transmit better price signals throughout the chain value. On the other extreme, the fishermen, we find that they place a positive economic value in a reduction of contamination in their fish as well, which could be aligned with the results for consumers, creating opportunities for Pareto improving measures in the regulations and prices which could translate into lower demand for more contaminated fish.

Fisheries, Fish Pollution and Biodiversity: Choice Experiments with Fishermen, Traders and Consumers

The increasing rates of per capita consumption of fish around the world should be a matter of concern for those interested in the threats to fishing stocks, aquatic biodiversity and human health. Fish consumption has positive health benefits but also brings higher risks of intake of heavy metals for humans. This increase in the demand for fish products has also been accompanied with fishing practices that threaten biodiversity. This article aims at evaluating from an economic perspective how important are these health and biodiversity components for those in the fish value chain, from fishermen to final consumers, using an experimental approach to estimate, through conjoint valuation techniques, the economic value of these aspects in the decision making of these agents. We find that final consumers place a significant economic value to the reduction of exposure to mercury contamination in fish; we also show that consumers respond positively to an education campaign showing the effects of mercury contained in fish, and that this money value could be used to create campaigns that transmit better price signals throughout the chain value. On the other extreme, the fishermen, we find that they place a positive economic value in a reduction of contamination in their fish as well, which could be aligned with the results for consumers, creating opportunities for Pareto improving measures in the regulations and prices which could translate into lower demand for more contaminated fish.

Distribution-free tolerance intervals with nomination samples: Applications to mercury contamination in fish

Tolerance intervals are enclosure intervals which will cover a fixed portion of the population distribution with a specified confidence. These intervals are widely used in clinical, environmental, biological and industrial applications, including quality control and environmental monitoring, to help determine limits for detection or assessment monitoring. In many of these applications the measurement of the variable of interest is costly and/or destructive but a small number of sampling units can be ranked easily by using expert-opinion knowledge or inexpensive and easily obtained measurements from these units. In this paper, we construct tolerance intervals based on the expensive measurements that are obtained using randomized nomination sampling (RNS) with the help of inexpensive auxiliary information. We study the performance of our proposed RNS-based tolerance intervals based on the corresponding coverage probabilities and the necessary sample size for their existence with those based on simple random sampling (SRS). The efficiency of the constructed RNS-based tolerance intervals compared to their SRS counterparts is discussed. We investigate the performance of RNS-based tolerance intervals for different values of the design parameters and various population shapes. We find the values of the design parameters which improve RNS over SRS. The RNS design in presence of ranking error is discussed and a new method for estimating ranking error probabilities is proposed. Theoretical results are augmented with numerical evaluations and a case study based on a fish mercury level dataset.

Prolonging Disaster (Un)recovery: “Culturally‐Irrelevant” Fish Consumption Advisories in the Keweenaw Bay Indian Community

AbstractThe United States responded to the 1971 international mercury crisis by establishing fish consumption advisories, which were intended to warn the American public of temporary mercury contamination in fish. However, advisories remain implemented as public health protection measures in all fifty states. This perpetual reliance on advisories is prolonging disaster recovery, or more precisely, ensuring a continuous state of what I term “disaster (un)recovery.” Modified approaches create “eat safe fish” guidance for fishers, producing “culturally‐relevant” recommendations. This means advisories offer a number of “healthy” choices that correspond to specific bodies of water and fish species favored by varying target populations. This article explores fish advisory policy in the Keweenaw Bay Indian Community (KBIC), a federally‐recognized Indian tribe that retains treaty‐established homelands and harvesting rights in the Lake Superior region. By using ethnographic and oral history methods, I examined fish harvest practices in an effort to create culturally‐relevant fish advisory recommendations for the community. However, my analysis reveals the cultural irrelevance of advisories as health protection measures for the KBIC. Examining cultural considerations within KBIC harvesting and in the development of fish advisories illustrates how the notion of “culture” actually leads to increased toxic exposure. The KBIC rely on fish for social and spiritual wellbeing, which simultaneously places their physical health at great risk. I argue that advisory policy as public health protection is primarily a social justice issue, and conclude by identifying pathways for culturally‐specific recovery.

Mercury contamination and exposure assessment of fishery products in Korea

In this study, total (T-Hg) and methyl mercury (Me-Hg) contamination was investigated in fishery products including canned fish, fish sauces, dried bonito and frozen tuna sashimi, collected from retail markets in Korea, to assess dietary exposure. Direct mercury analyser and gas chromatography-electron captured detector were employed to measure T-Hg and Me-Hg, respectively. The highest T-Hg and Me-Hg contamination was present in tuna sashimi, followed by dried bonito, respectively. Canned tuna showed more frequent detection and higher content than other canned fishery products. The weekly exposure estimate indicates that exposure to mercury from fishery products is safe, showing 2.59% provisional tolerable weekly intake (PTWI) for T-Hg, 1.82% PTWI for Me-Hg and 4.16% reference dose for Me-Hg. However, it should be addressed to monitor the mercury contamination in fish and fishery products regularly, to safeguard vulnerable population such as children, to limit intake of these food products.

Mercury contamination in fish and human hair from Hainan Island, South China Sea: Implication for human exposure

Hair has long been recognized as a good biomarker for human exposure to Hg. The mercury concentrations in 14 species of marine fish and hair samples from 177 coastal residents in Hainan, South China Sea were investigated to assess the status of mercury exposure associated with marine fish consumption. Concentrations of total Hg (THg) and methylmercury (MeHg) in the fish muscles were 0.094±0.008 and 0.066±0.006μg/gww, respectively, which were far below the limit considered safe for consumption (0.5μg/g). The average THg concentrations in hair of adults (1.02±0.92μg/g) were lower than the provisional tolerable weekly intake (PTWI) level of 2.2μg/g. However, 23.7% of children had a hair THg level exceeding the RfD level of 1μg/g, indicating a great risk of Hg exposure to children via fish consumption. The concentration of THg in hair was significantly correlated with fish consumption but not with gender-specific fish intake. With higher fish consumption frequency, the fishermen had significantly elevated hair Hg levels compared to the students and the other general public, who had similar hair THg levels but different fish consumption patterns, indicating the existence of other sources of Hg exposure to the residents of Hainan Island.

Comparative study of mercury speciation in commercial fishes of the Brazilian Amazon

Mercury is responsible for serious episodes of environmental pollution throughout the world, especially in the Amazon. This toxicity has led regulatory agencies to focus on fish as the target organism for protecting the health of humans and other sensitive organisms. Unfortunately, in the Amazon area, different sampling strategies and the wide variety of sampling areas and fish species make it extremely difficult to determine relationships across geographic regions or over time to ascertain historical trends. Thus, the aim of this work was to achieve three main objectives: a comparative study of mercury contamination in fish of Itaituba (Tapajós, located downstream of the largest gold-mining region in Amazon) and Belém (an area non-exposed to mercury pollution of anthropogenic origin), perform an analysis of inorganic mercury (IHg) versus monomethylmercury (MeHg) contents, and, finally, compare mercury contamination in Tapajós over time. Five piscivorous species were obtained in Itaituba and Belém. Also, four non-piscivorous species were collected in Itaituba. For the first time, mercury speciation showed that (1) current MeHg levels in piscivorous species in Tapajós are higher than those of the non-exposed area, (2) piscivorous species from Itaituba (dourada, filhote, and sarda) contained mercury levels above the World Health Organization safety limit (~17%) and/or above the US Environmental Protection Agency tissue residue criterion (40%), (3) increased MeHg is usually accompanied by increased IHg, and (4) the mean total mercury concentrations for piscivorous species in Itaituba were within the same range and, associated uncertainties as those previously reported, although a remarkable decreasing trend over time was observed for mean total Hg concentrations in non-piscivorous species from Itaituba. The present study supports the importance of continuous monitoring of both populations in the Amazon Rivers. Our results will better assist the development of preventive strategies and governmental actions to confront the problem of mercury contamination in the Amazon.