Study on the Effects of Methyl Mercury

Study on the Effects of Methyl MercuryKOLIANDRIS Damianos EHS 519IntroductionMethyl hectogram is ranked in the top ten groups of chemicals listed as environgenial problem globally and is significant associated for human race health issues8, 10. Published literature suggests that methyl mercury is suspected to have negative effects brain schooling and the consumption of this compound pregnant woman may eventually lead significant neurological defects in newborns13.We will identify the adverse effects (if any) of methyl mercury by examining major epidemiological and animal studies and using the mean levels of image, we will assess the level of exposure of methyl mercury and work fall out the BMDL and RfD.Hazard IdentificationWe will study Mercury. Mercury exists in different forms, either in elements (or metals) as inorganic form (occupational exposure) and organic form such as methyl mercury (dietary exposure) 1.Mercury, a natural element in water, soil and air, is considered by WHO as one of the top 10 groups of chemicals of major public health concern1. Methyl Mercury primarily targets the nervous system during its advance(prenominal) development1. That is why foetuses and young children be mostly vulnerable to Methyl Mercurys adverse health effects. Methyl Mercury is oxidised in the brain and causes chronic diseases 2,3,4,5.Specifically, in the Faroe Islands, people consume whale meat at genuinely mellow rates. The world was found to be highly contaminated and the researchers associated europsychological deficits at 7 years of age Developmental delays with the methylmercury exposures6.The Faroe Islands and New Zealand studies provide evidence of a negative association between methylmercury in seafood consumed by pregnant women and the neurodevelopmental capabilities of the siblings at the age of 4 and 6-7 years old. Even in low concent symmetryns of methylercury, the effects ar small but still there 6,8The Seychelles study did not detect any sig nificant associations between developmental tests and methylmercury exposure. The study measured concentration of blur mercury in pregnant mothers and then evaluated the development capabilities of children at 6.5, 19, 29 and 66 months of age7. From the study there is no evidence about the association of MeHg exposure and DDST-R where was showed in pilot study7.The New Zealand study associated exposure to Methyl mercury with mental development of children at the age of 4 and 6-7 years old8. The study habilitate a high exposure group consisted of 200 children (mean exposure = 9g/g) at the age of 6 to 7 years old, lower mental capabilities were observed as opposed to the Control group with lower exposure rates. Nevertheless, JEFCA posed several methodological questions on this study1, 7.Exposure assessmentVarious epidemiological studies were conducted in which researchers assed the level of exposure of the mothers of the children. Noteworthy attention is given in the study in the Fa roe Islands6, in Seychelles7 and in New Zealand8.The studies we examined 6,7,8 and the report for WHO1, suggest that the population is primarily exposed through seafood consumption. Since methylmercury oxidises in the brain during early development stages, the adverse effects are apparent to foetuses and young children where cognitive capabilities are in general affected.The population of Faroe Islands is not more than 50,000 people and the New Zealand is roughly 4.5 million. It is evident that population that resides in islands and fish consumption is highly observed, and then the exposure is of high rates. Typical levels of fish consumption vary between 1g/g and 9g/g (Faroe) and sometimes higher (10g/g in New Zealand).The Joint FAO/WHO Expert Committee on Food Additives (JECFA) determined that a steady-state daily ingestion of methylmercury of 1.5 g/kg torso pack/day would result in the concentration in maternal squanderer estimation1.Table 1 GUIDANCE FOR IDENTIFYING POPULATIO NS AT RISK FROM MERCURY EXPOSURE, August 2008, Issued by UNEP DTIE Chemicals Branch and WHO Department of Food Safety, Zoonoses and Foodborne distempersDose-Response AnalysisThe population in Faroe Islands was found to be highly contaminated of about 2 mg methyl mercury/kg6. The results were also (statistically) significant even when they excluded children whose mothers exceed 10 g/g 6. This study included many neuropsychological tests such as Finger Tapping, Hand-Eye Coordination, an news program scale (Wechsler), Similarities, and Block Designs, Visual and verbal tests by Bender6.The 3 studies (Faroe, N. Zealand and Seychelles) were used by the US EPA to derive an RfD of 0.11 g/Kg boy weight per day for methyl mercury. The benchmark dose was derived with an uncertainty factor of 10 and based on the 95% confidence levels of the 3 studies1. The Joint FAO/WHO Expert Committee on Food Additives concluded pregnant women exposure to methyl mercury neurotoxic effects were the most sens itive health outcome of the 3 studies.Original BMDLs of 1724mg/kg were produced. Nevertheless, a single observation in the New Zealand study (86g/Kg) seemed to inflate this BMDL, and when omitted a BMDLs of 7.410mg/kg was derived.Minor adverse effects are expected when the threshold of 0.056g/l is not exceed1. This threshold was obtained by dividing a maternal hair-mercury concentration of 14mg/kg by the hair blood ratio of 250. In humans, the steady state concentration of mercury in blood can be related to average daily intake using a one-compartment model that incorporates refinements to the original WHO formula, as followsu1Using this equation, the Committee determined that a steady-state daily ingestion of methyl mercury at 1.5 mg/kg of body weight per day would result in a maternal blood-mercury concentration that would have no appreciable adverse effects on offspring in these two study populations.Potential human variability was taken into account by the application of adjustm ent or uncertainty factors such as sink individual variation in pharmacokineticsRisk CharacterisationMercury, a natural element in water, soil and air, is considered by WHO as one of the top 10 groups of chemicals of major public health concern1. Exposure to mercury even small amounts causes major health problems, and is treated for the development of the child in utero in early years. 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