Communicating Methylmercury Risks and Fish Consumption Benefits to Vulnerable Childbearing Populations

Mercury in aquatic fauna contamination: A systematic review on its dynamics and potential health risks

Mercury is an important pollutant, released into aquatic ecosystems both naturally and by anthropogenic action. This element is transferred to aquatic organisms in different ways, causing potential health risks. In addition, mercury can be accumulated by humans, especially through the consumption of contaminated food. This systematic review aims to present mercury pathways, the major routes through which this element reaches the aquatic environment and its transformations until becoming available to living animals, leading to bioaccumulation and biomagnification phenomena. The key biotic and abiotic factors affecting such processes, the impact of mercury on animal and human health and the issue of seafood consumption as a source of chronic mercury contamination are also addressed. A total of 101 articles were retrieved from a standardized search on three databases (PubMed, Emabse, and Web of Science), in addition to 28 other studies not found on these databases but considered fundamental to this review (totaling 129 articles). Both biotic and abiotic factors display fundamental importance in mediating mercurial dynamics, i.e., muscle tropism, and salinity, respectively. Consequently, mercurial contamination in aquatic environments affects animal health, especially the risk of extinction species and also on human health, with methylmercury the main mercury species responsible for acute and chronic symptomatology.

Perceptions about mercury and lead in fish consumed in Lake Albert fishing communities Uganda

Fish consumption is a lifestyle in fishing communities influenced by individual and communal perceptions. However, information about individual perceptions about fish consumption in the vulnerable fishing community in a developing country is lacking. Without this study, the benefits of fish consumption in a vulnerable community may not be realized. Data collection was executed using key informant interviews and survey structured questionnaires. The key informants include fisheries, community development, veterinary, community and environmental officers. The household heads were the respondents. The Qualitative data was organized and queried using QSR Nvivo 10 and quantitative data analyzed with SPSS version 22. The perceived benefits of eating fish are health, income, nutrition and manhood. The perceived risks are Stigma and ill health. The factors increasing fish consumption are heedless of fish consumption benefits (p = 0.041) and household size i.e. number of adults more than seven (p = 0.020). Those decreasing are methods of preparation of fish i.e. boiling and frying (p = 0.019 and p = 0.010) and oblivious about organizations dealing with fishing activities (p = 0.029). An awareness campaign is needed to demystify the health benefits and fallacies of fish consumption. The knowledge on individual perceptions associated with fish consumption will increase fish consumption but with fewer risks.

Mercury, selenium and fish oils in marine food webs and implications for human health

Humans who eat fish are exposed to mixtures of healthful nutrients and harmful contaminants that are influenced by environmental and ecological factors. Marine fisheries are composed of a multitude of species with varying life histories, and harvested in oceans, coastal waters and estuaries where environmental and ecological conditions determine fish exposure to both nutrients and contaminants. Many of these nutrients and contaminants are thought to influence similar health outcomes (i.e., neurological, cardiovascular, immunological systems). Therefore, our understanding of the risks and benefits of consuming seafood require balanced assessments of contaminants and nutrients found in fish and shellfish. In this paper, we review some of the reported benefits of fish consumption with a focus on the potential hazards of mercury exposure, and compare the environmental variability of fish oils, selenium and mercury in fish. A major scientific gap identified is that fish tissue concentrations are rarely measured for both contaminants and nutrients across a range of species and geographic regions. Interpreting the implications of seafood for human health will require a better understanding of these multiple exposures, particularly as environmental conditions in the oceans change.

Developmental Origins of Health and Disease: A Challenge for Nurses

Prevention of disease is a cornerstone of nursing care. Through our endeavors in research, teaching, and clinical care, nurses consistently seek to change the trajectory of disease development. The theoretical framework known as the Developmental Origins of Health and Disease (DOHaD) offers a new lens that shifts the current disease prevention paradigm upstream, encouraging intensified care of pregnant girls/women, neonates, and infants. This new focus parallels other emerging ecobiodevelopmental, life-course theories, which identify the long-term impact of early environments and stressors on the later risk of chronic adult diseases. Nurses have the potential to influence the health of multiple generations by incorporating DOHaD perspectives and interventions into their research and patient care.

How can more women of childbearing age be encouraged to follow fish consumption recommendations?

Several studies show that most women do not consume enough fish during pregnancy (and afterward) to derive the maximum health benefits for themselves and their babies, according to the USDA guidelines. We engaged in a two-part study to better understand what might be done to encourage women of childbearing age to eat healthy fish-a mail survey of women who recently gave birth in Minnesota, Wisconsin, and Pennsylvania, and six focus groups with women of childbearing age living in the Great Lakes region. Similar to other studies, we found that many women changed their behavior and consumed less fish during pregnancy than before. Most women reported receiving information, primarily during pregnancy, about the types of fish and how much fish to eat. As a result, increasing access to information during pregnancy likely would not result in increasing many women's fish consumption. Based on our examination of factors influencing women to try to follow the recommendations, the strongest connection with trying to follow the recommendations was receiving enough information to decide and believing that eating fish was good for the baby. Focus group participants also reported that messages about the specific health benefits of fish consumption for their children were particularly influential. These findings suggest that refining messages through testing might be a valuable approach toward increasing women's consumption of less-contaminated fish.

Web-based environmental health education: fish facts

Nurses and other health professionals are often asked about the benefits and risks of fish consumption. The combination of conflicting media messages about these risks and benefits and limited knowledge has led to confusion about how to properly advise people about safe fish consumption. "Fish Facts for Health Professionals" was the result of a collaborative effort of environmental, public health, medical, nursing, and media experts to create a web-based educational series to address the need for reliable information on fish consumption. Using interviews and real case studies, the 3- to 5-minute media modules provided a strong visual element while remaining conversational. The modules were viewed worldwide, and 121 participants successfully completed the requirements for professional continuing education credit.

Effects of methylmercury exposure on neuronal differentiation of mouse and human embryonic stem cells

The establishment of more efficient in vitro approaches has been widely acknowledged as a critical need for toxicity testing. In this study, we examined the effects of methylmercury (MeHg), which is a well-known developmental neurotoxicant, in two neuronal differentiation systems of mouse and human embryonic stem cells (mESCs and hESCs, respectively). Embryoid bodies were generated from gathering of mESCs and hESCs using a micro-device and seeded onto ornithine-laminin-coated plates to promote proliferation and neuronal differentiation. The cells were exposed to MeHg from the start of neuronal induction until the termination of cultures, and significant reductions of mESCs and hESCs were observed in the cell viability assays at 1,10,100 and 1000nM, respectively. Although the mESC derivatives were more sensitive than the hESC derivatives to MeHg exposure in terms of cell viability, the morphological evaluation demonstrated that the neurite length and branch points of hESC derivatives were more susceptible to a low concentration of MeHg. Then, the mRNA levels of differentiation markers were examined using quantitative RT-PCR analysis and the interactions between MeHg exposure and gene expression levels were visualized using a network model based on a Bayesian algorithm. The Bayesian network analysis showed that a MeHg-node was located on the highest hierarchy in the hESC derivatives, but not in the mESC derivatives, suggesting that MeHg directly affect differentiation marker genes in hESCs. Taken together, effects of MeHg were observed in our neuronal differentiation systems of mESCs and hESCs using a combination of morphological and molecular markers. Our study provided possible, but limited, evidences that human ESC models might be more sensitive in particular endpoints in response to MeHg exposure than that in mouse ESC models. Further investigations that expand on the findings of the present paper may solve problems that occur when the outcomes from laboratory animals are extrapolated for human risk evaluation.