A contribution to the establishment of reference values for total mercury levels in hair and fish in amazonia.

Studies on mercury levels in the Amazonian Region have typically lacked background or reference parameters. A sectional study on Hg concentration in hair and fish was conducted, together with an assessment of the prevalence of signs and symptoms related to Hg poisoning, in four communities in the Amazon Basin not impacted by gold mining, located either by a river course (Santana do Ituqui and Caxiuanã) or by a lake (Aldeia do Lago Grande and Vila do Tabatinga). Mercury determinations in hair and fish were made by flameless atomic absorption spectrophotometry. Mean total Hg in hair was 4.33 microg/g (0.40-11.60 microg/g) in 321 individuals from Santana do Ituqui, 3.98 microg/g (0.40-11.76 microg/g) for 316 persons in Aldeia do Lago Grande, 5.46 microg/g (0.37-49.85 microg/g) for 504 individuals from Vila do Tabatinga and 8.58 microg/g (0.61-45.59 microg/g) for 203 inhabitants from Caxiuanã. Fish consumption was very high in all those communities but no signs or symptoms associated with Hg poisoning were found. Mean Hg concentration in fish varied from 0.006 to 2.529 microg/g for carnivores and from 0.008 to 0.871 microg/g for noncarnivores. These values suggest that further studies including a larger number of communities would eventually lead to values of "normal" Hg concentration in the Amazonian Region quite above the limits suggested by the World Health Organization.

Mercury contamination of fish and exposures of an indigenous community in Pará state, Brazil.

Fish consumption is an important source of protein among indigenous communities in Amazonian Brazil. Exposures to mercury via fish were studied in an indigenous community of the Munduruku reserve, located in the Tapajós River basin in the state of Pará, one of the oldest and most productive gold mining areas in the Amazon region. This study summarizes the results of mercury (Hg) analyses of fish consumed by inhabitants of the Munduruku settlement of Sai Cinza. The most frequently consumed fish, reported by 330 persons interviewed for this study, were tucunaré, pacu, jaraqui, traíra, aracu, matrinchã, and caratinga. The mean mercury concentration in carnivorous fish was 0.297 microg.g(-1) while in noncarnivorous fish mean mercury concentration was 0.095 microg.g(-1). Only in caratinga was there a significant relationship between fish size, weight, and mercury levels. Levels of methylmercury in the tucunaré averaged 0.170 microg.g(-1), while in traíra the mean level of methylmercury was 0.212 microg.g(-1). Although the levels of Hg in fish consumed by the Sai Cinza community are below the Brazilian limit value for consumption, the high rates and amounts of fish consumed by this population are relevant to evaluating risks of mercury contamination for communities with limited food resources.

Mercury exposures in riverside Amazon communities in Pará, Brazil.

Cross-sectional studies were conducted in three riverside communities in the state of Pará in the Amazon Region of Brazil. Two of these communities, Brasília Legal and São Luís do Tapajós, are located in a watershed exposed to mercury pollution from artisanal gold mining, and the third, Santana do Ituqui, is outside this area. The studies were based upon a community census and included all persons volunteering for participation in each community. All participants were surveyed by questionnaire for health history, occupation, residence, and diet. Clinical evaluations were also done on each subject, along with collection of blood, urine, feces, and hair. Fish samples were collected to represent the most frequently consumed species. Mercury was measured in hair and fish. Although no signs or symptoms of overt mercury intoxication were observed, persons in Brasília Legal and São Luís do Tapajós had higher levels of mercury in hair than residents of Santana de Ituqui, located out of the risk area. Levels of mercury in fish were below Brazilian health guidance limits, but the high rates of fish consumption among these populations raise concerns for the possible effects of chronic exposure, especially among young children and women of childbearing age.

[Mercury levels in fish consumed by the Sai Cinza indigenous community, Munduruku Reservation, Jacareacanga County, State of Pará, Brazil]. / Níveis de mercúrio em peixes consumidos pela comunidade indígena de Sai Cinza na Reserva Munduruku, Município de Jacareacanga, Estado do Pará, Brasil.

This study evaluated fish consumption and mercury levels in fish consumed by an indigenous community in the State of Pará. Eighty fish samples were collected (barbado, surubim, traíra, tucunaré, piranha, aruanã, caratinga, aracu, mandiá, jandiá, and pacu). Mercury analysis was performed using a Mercury Analyzer HG-3500. Average mercury concentration in carnivorous species was 0.293 (g/g (SD=0.104), while in non-carnivorous species it was 0.112 (g/g (SD=0. 036). Brazilian legislation establishes a maximum permissible limit of 0.5 (g/g for fish consumption. No significant correlation was found between fish length or weight and mercury concentration. Types of fish most frequently consumed by the community were tucunaré, pacu, jaraqui, traíra, aracu, matrinchã, and caratinga. Carnivorous species, especially tucunaré and traíra, amongst the most frequently eaten, had higher mercury levels than non-carnivorous species. Frequency of consumption is crucial to assess the risk of mercury contamination in communities who lack alternative food sources.

[Diagnosis of health conditions in a pan-mining community in the Tapajós River Basin, Itaituba, Par , Brazil, 1992]. / Diagnóstico das condições de saúde de uma comunidade garimpeira na regiõ o do Rio Tapajós, Itaituba, Pará, Brasil, 1992.

The purpose of this article is to describe health conditions in a pan-mining community, in particular the interaction of mercury contamination with other health problems. This study was carried out in a panning mine located on Rato Creek, a tributary of the Tapajó s River Basin in the municipality of Itaituba, State of Par The study population consisted of 223 individuals. An epidemiological questionnaire was applied, medical treatment was given, and biological specimens were collected. Testing of fecal samples showed that 96.1% of the individuals had parasites and 66.4% were anemic. Prevalence of hepatitis B virus was 85.0%, and 11 individuals (6.0%) were virus carriers (HBsAg positive). Of 186 patients tested for malaria, 65 individuals (35.0%) had the infection, of whom 34 (52.3%) were asymptomatic. Prevalence of syphillis was 41.6%. Urine mercury levels were measured in 173 individuals. Some 16 (9.2%) of those tested had mercury levels between 10 and 19 ug/l, while 9 patients (5.2%) had levels above 20 ug/l. An overview of general health conditions showed a combination of problems in individuals, who lacked adequate diagnosis, in addition to a high level of self-medication, given the absence of health facilities. In addition, these individuals are threatened by critical levels of mercury contamination. In conclusion, this article gives a general overview of health conditions in these pan-mining communities, demonstrating the multicausal nature of health conditions in the Amazon region, a fact which should be considered when planning appropriate strategies for clinical treatment.