Human health risk of methylmercury from fish consumption at the largest floodplain in Colombia.

Colombia is one of the countries with the highest emissions of mercury (Hg) to the environment, due to its use in gold mining. This study evaluated the human health risk from exposure to Hg through fish consumption in 11 municipalities located in the Mojana region, northern Colombia. The study participants (n = 839) were categorized into three population groups: children (CHD), women of childbearing age (WCHA) and the rest of population (RP). Total Hg (THg) and methylmercury (MeHg) concentrations were evaluated in the top ten most consumed fish species (n = 292). Median concentrations (range: 0.22-0.58 µg/g ww) of the five carnivorous fish species exceeded the reference limit established by FAO/WHO (0.2 µg/g ww) for vulnerable populations. For 6 of the 10 studied fish species, the estimated weekly intake (EWI) in children was above the provisional tolerable weekly intake (PTWI, 1.6 µg/kg bw/week) of MeHg established by JECFA. EWI values for WCHA were above PTWI in 4 fish species, whereas in general, for RP group values were below PTWI (3.2 µg/kg bw/week). Our assessment of potential risks to MeHg exposure indicated that most of the consumed fish could generate negative effects in vulnerable groups, because according to ingestion rate, MeHg permissible is, in some cases, up to 4 times higher than reference limits. Consumption advisories should be a guidance to avoid risk, gain nutritional benefits, and sustain fish populations. Because its high MeHg levels as well as high ingestion, it is recommended that inhabitants of this region should stop eating certain kinds of fish and the whole fish as a single meal. To reduce its harmful intake, we have proposed a didactic strategy based on marbles that control the portion of fish they are eating.

Mercury, Methylmercury and other Heavy Metals in Fish in Colombia: Risk From Ingestion / Mercurio, metilmercurio y otros metales pesados en peces de colombia: riesgo por ingesta

RESUMEN En 2013 el pescado proporcionó a más de 3100 millones de personas casi el 20 % de la ingesta promedio de proteínas de origen animal per cápita (FAO, 2016). De acuerdo con el Programa de las Naciones Unidas para el Desarrollo (PNUD), en Colombia y, particularmente en las poblaciones ribereñas y costeras, el 90 % del consumo de proteína de origen animal proviene del pescado, como resultado de un acceso muy bajo a otro tipo de proteínas. Colombia enfrenta uno de los mayores problemas por contaminación ambiental a nivel mundial, generado en gran parte por el abuso de sustancias químicas para el aprovechamiento de minerales, mala disposición de aguas servidas y prácticas industriales y agrícolas inadecuadas, en cuerpos de aguas fundamentales para la dinámica poblacional de animales, vegetales y humanos. Como estrategia mundial para reducir los riesgos a la salud humana por consumo de pescado contaminado con metales pesados, se han considerado límites máximos permisibles, propuestos por diferentes entidades; sin embargo, el 31,5 % de los resultados de estudios publicados para Colombia, son superiores al límite permisible recomendado por la OMS (0,5 μg/g). Los resultados presentados en esta revisión evidencian la urgente necesidad de realizar estudios que evalúen el riesgo a la salud que enfrentan pobladores de zonas mineras y no mineras de Colombia, aportará también fundamentos científicos y bases para el establecimiento de ejes estratégicos que permitan la puesta en marcha de nuevos proyectos productivos que ofrezcan el acceso de la población a diversas fuentes de alimentación.

ABSTRACT In 2013, fish provided to more of 3100 million people about 20 % of the average intake of animal protein per capita (FAO, 2016). According to the United Nations Development Program (UNDP), in Colombia and, particularly in the coastal populations, 90 % of the protein consumption of animal origin comes from fish, mainly as a result of very low access comparing it with another type of proteins. Colombia faces one of the biggest problems due to global environmental pollution, generated in largely part by the abuse of chemical substances for the exploitation of minerals, poor disposal of wastewater and inadequate industrial and agricultural practices, in bodies of natural water essential for population dynamics of animals, plants and humans. As a global strategy to reduce the risks to human health from the consumption of fish contaminated with heavy metals, maximum permissible limits have been considered, proposed by different entities. However, 31.5 % of the results of studies published for Colombia, register higher than the permissible limit recommended by the WHO (0.5 μg/g). The results presented in this review, evidence the urgent need to conduct studies that assess the health risk faced by residents of mining and non-mining areas of Colombia, will also provide scientific foundations and bases for the establishment of strategic axes that permit the start-up of new productive projects, which offer the population access to various sources of food.