Mercury contamination in humans in Upper Maroni, French Guiana between 2004 and 2009.

We measured hair mercury concentration in Amerindians between 2004 and 2009 in Upper Maroni, French Guiana. Hair samples were collected from 387 residents (males: 153, females: 234). Average hair mercury concentration was high (males: 9.4 ppm, females: 9.9 ppm). We examined fish consumption by 37 residents. There was a significant correlation between hair mercury concentration and fish consumption. We also measured mercury concentration in polluted fish in upper reaches of the Maroni River. Muscle mercury concentrations were high in the fish. These results indicate that current high hair mercury concentrations in Amerindians remain linked to fish consumption.

Mercury in hair as a biomarker of exposure in a coastal Venezuelan population.

To assess mercury exposure and potential risk, total mercury (THg-H) and methylmercury (MeHg-H) in hair were studied in 160 adults. The study group consisted of 60 individuals living in the north central coast of Venezuela. A section of the area was known to be contaminated with mercury from a chlor-alkali plant installed near one of the tributary rivers of the Caribbean Sea. The study group was selected from 4 inclusion criteria points. The control group was composed of 100 individuals selected from Carabobo state with no known exposure to Hg. A questionnaire was designed to collect demographic, health information, work activities and fish consumption habits. Hair samples were analyzed for THg. Samples with THg-H > 5 microg/g were also analyzed for MeHg. The mean THg-H was 1.88 +/- 1.50 and 0.99 +/- 0.87 microg/g for the study and control groups, respectively. The study group was statistically higher than control individuals, however, no statistical differences of THg-H were found between each of the 4 categories of both groups. Mean MeHg-H value was 3.67 +/- 1.25 microg/g. Associations were made between Hg-H and several variables. No significant relationship was noted between Hg-H levels and clinical symptoms. R analyses and t-tests were used to determine associations between questionnaire variables and THg-H. The main predictors of THg-H levels in the study group were fish consumption and frequency. As both groups presented relatively low values for THg-H and MeHg-H, the results of this study indicate that Hg exposure did not exceed safe levels. However, a more in-depth exposure assessment should be conducted to more accurately assess this exposure, specifically in terms of Hg content in water and fish sampling.

Mercury in hair as a biomarker of exposure in a coastal Venezuelan population

Mercurio total y metil mercurio en cabello (THg-H y MeHg-H) fueron determinados en 160 adultos para caracterizar esta población en términos de exposición a Hg y su potencial riesgo. El grupo Estudio consistió de 60 individuos que viven en la costa Centro-Norte de Venezuela. Parte de esta  rea se había reportado contaminada, años atrás, con Hg de una planta de cloro-soda instalada junto a uno de los ríos tributarios del mar Caribe. El grupo Estudio se seleccionó con base en 4 criterios de inclusión. El grupo Control estuvo compuesto de 100 individuos del Estado Carabobo, sin exposición conocida a Hg. Se administró un cuestionario para obtener información referida a: demografía, salud, actividades laborales y alimentación con pescado. Se analizaron muestras de cabello para determinar THg. Las que resultaron superiores a 5 µg/g, se analizaron también para MeHg. El promedio de THg-H fue de 1,88 ± 1,50 y 0,99 ± 0,87 µg/g para los grupos estudio y control respectivamente. El grupo estudio resultó estadísticamente superior al control, sin embargo, no se hallaron diferencias estadísticamente significantes en el THg-H comparando cada una de las 4 categorías del grupo estudio. La media de MeHg-H fue de 3,67 ± 1,25 æg/g. Se calcularon asociaciones entre Hg-H y algunas variables. No se encontró una relación significativa entre los niveles de Hg-H y los síntomas reportados. Se usaron R-análisis y t-test y para examinar las asociaciones individuales entre las variables del cuestionario y el THg-H. Los principales predictores de los niveles de THg-H en el grupo Estudio fueron el consumo de pescado y su frecuencia. Ya que ambos grupos estudiados presentaron valores relativamente bajos de THg-H y MeHg-H, los resultados de este estudio indican que la exposición a Hg no excedió los niveles permisibles.