title: Methylmercury in fish and hair samples from the Balbina Feservoir, Brazilian Amazon.
abstract: The present study aimed to evaluate methylmercury in fish and human hair samples from an important hydroelectrical reservoir, Balbina (Brazil, Amazon). It presents a quite intense fishing activity and there is no known goldmining activity in its watershed. Fish and human hair were analyzed with a new extraction technique and measured by GC-ECD. Analytical quality was checked through intercomparisons between two laboratories with local samples and certified standards from IAEA. Methylmercury in hair ranged from 2.0 to 21.6 microg . g-1 with a mean of 8.76+/-5.20 microg . g-1 (N=20), while the methylmercury percentages were above 90. Fish presented methylmercury levels ranging from 0.03 to 0.9 microg small middle dot g-1 wet wt with a mean of 0.24+/-0.18 microg small middle dot g-1 wet wt (N=32), which is below the limit established for food by Brazilian legislation (0.5 microg small middle dot g-1 wet wt) and methylmercury mean percentages were above 95%. The total mean daily methylmercury intake ranged from 11 to 55 microg for 70% of the sampled population from the village based on a daily consumption of about 110 g of fish with methylmercury concentrations in the range of 0.1 to 0.5 microg . g-1. This calculation is consistent with methylmercury concentrations in hair samples in the range of 2.6 to 13.1 microg . g-1.
authors.affiliation: Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Rio de Janeiro, UFRJ, 21949-900, Brazil. kehrig@leao.biof.ufrj.br
authors.forename: H A
authors.initials: HA
authors.lastname: Kehrig
authors.forename: O
authors.initials: O
authors.lastname: Malm
authors.forename: H
authors.initials: H
authors.lastname: Akagi
authors.forename: J R
authors.initials: JR
authors.lastname: Guimarães
authors.forename: J P
authors.initials: JP
authors.lastname: Torres
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001938:Brazil / Q000453:epidemiology; D002675:Child, Preschool; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D005399:Fishes; D005506:Food Contamination / Q000032:analysis; D006197:Hair / Q000737:chemistry*; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D018811:Maternal Exposure / Q000009:adverse effects; D008628:Mercury / Q000008:administration & dosage / Q000009:adverse effects / Q000032:analysis*; D008630:Mercury Poisoning / Q000453:epidemiology / Q000209:etiology; D008767:Methylmercury Compounds / Q000008:administration & dosage / Q000009:adverse effects / Q000032:analysis*; D009132:Muscles / Q000737:chemistry; D011247:Pregnancy; D015203:Reproducibility of Results; D017747:Seafood / Q000009:adverse effects; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000009:adverse effects
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury