Fishing activity, health characteristics and mercury exposure of Amerindian women living alongside the Beni River (Amazonian Bolivia)

Abstract

Populations in Bolivian Amazonia are exposed to mercury contamination through fish ingestion. A group of 170 Amerindian women living along the banks of the Beni River were examined in order to detect any adverse effects on their health consistent with the toxic effects of mercury. The mercury content of the women's hair (H-Hg) was used as the bio-indicator of mercury exposure. The women answered a 24-hour food recall questionnaire on the frequency of their fish consumption. They also underwent a clinical examination with their weight, stature, hemoglobinemia hemoglobin concentration in blood, and blood pressure being recorded. Significant relationships were found between fishing practices, the frequency of fish consumption and H-Hg levels with mercury contaminated women (H-Hg > 5 µg/g) being more likely to present neurological abnormalities (paresthesia, static and dynamic imbalance, poor motor coordination) than non-contaminated women.. No relationship was found between blood pressure and mercury levels. Women with higher H-Hg reported more infant deaths than did women with lower levels. A logistic regression analysis which included socio cultural traits, fish consumption habits and health characteristics was performed in order to determine the risks of contamination. Contaminated women were more likely to belong to those communities pursuing traditional fishing activities; moreover these women tended to be younger and frailer than other. They also exhibited mild neurological abnormalities and reported more infant deaths. These findings should stimulate local communities to take preventive actions directed towards the more "traditional" and vulnerable groups of population.

Estimation of Seasonal Risk Caused by the Intake of Lead, Mercury and Cadmium through Freshwater Fish Consumption from Urban Water Reservoirs in Arid Areas of Northern Mexico

“…It has been also reported that the consumption of 150 g of either louvar or swordfish, acquired from fish retailers in Madrid (Spain), exceeded the recommended value of PTWI for mercury in women in childbearing age, whereas for Cd and Pb it did not [ 53 ]. This is an important issue, considering the human health threats associated with methyl mercury exposure through intake [ 1 , 15 ] affecting public health, mainly in children [ 54 ].…”

“…Prenatal exposure through consumption of fish with high concentrations of methyl mercury causes serious diseases, such as cerebral palsy, mental retardation, neurological abnormalities and more infant mortality [ 1 , 15 ].…”

Scientific Opinion on the risk for public health related to the presence of mercury and methylmercury in food

“…The authors concluded that overall, the data did not provide strong evidence for an association between mercury in blood and lower scores on neurobehavioural performance tests in this population. Benefice et al (2010) examined neurological abnormalities and blood pressure among two ethnic groups of Amerindian women living along the banks of the Beni River (n = 170). Total mercury in hair (mean 5.5, SD 4.2 mg/kg) and frequency of fish consumption was recorded by a 24-h food recall questionnaire.…”

Benefits and risks of fish consumption for the human health

“…Thus, evidences between exposure to mercury and an increase in the risk of heart diseases were not observed, although Benefice et al 44 suggest that there may be a relation with higher susceptibility of developing other diseases, such as neurological disorders.…”

“…Benefice et al 44 reported that the increase in blood mercury levels among Amerindians living in the Bolivian Amazon, also related with fish consumption, was associated with a higher susceptibility in developing neurological disorders. .Most of the other studies that explain the risks of fish consumption are limited to identification and quantification of contaminants in varied species.…”