Mercury in hair and in fish consumed by Riparian women of the Rio Negro,Amazon, Brazil

This work puts the risks and benefits of a mercury acquisition through a fish-dominated diet in the context of the other endemic health problems in the Amazon. Fish consumption rate was assessed after determining mercury concentrations in the most consumed fish and in hair of women at fertile age (15 to 45 years of age), living in remote localities of the Rio Negro basin (not impacted by gold mining). Fish-meals were consumed once a day (7.1%) but in most cases (78.6 %) at least twice a day with an estimated mean fish consumption rate of 170.5 g (range 23 to 293 g). The fish-species most preferred were Tucunarés (Cichla spp), Pacus (Mylossoma aureum and Myleus micans), Piranhas (Sarrasalmus spp), Cará (Satanoperca jurupari), Jaraquí (Semaprochilodus taeniurus). The mean Hg concentration in these species varies widely (38 to 592 ng g(- 1)) but 27% of samples had Hg concentrations above 500 ng g(- 1), and only 7% were above 1000 ng g(- 1). The hair-Hg concentrations ranged from 6.5 to 32.6 microg g(- 1) with 82% of them having concentrations above 10 microg g(- 1) (w.w.) hair. Hair-Hg concentrations were positively correlated with women's age (r=0.4500; P=0.0111). Clinical evaluation did not detected symptoms (paraparesis, tremor, numbness of limbs, sensory disturbances) compatible with Minamata disease, but there was a high (71%) incidence of clinical history of malaria. Fish is an abundant natural resource, rich in essential nutrients and important to the diet of 'ribeirinhos' of Brazilian Amazonia. We hypothesize that lack of basic medical care in these communities outweighs risk of naturally occurring fish-MMHg. Therefore food habits based on fish consumption is part of a successful strategy for survival and should be considered as a health asset.     

Mercury levels in tissues of Giant otters (Pteronura brasiliensis) from the Rio Negro, Pantanal, Brazil

This research reports the first data on mercury levels found in Giant otters (Pteronura brasiliensis) from South America. Mercury concentrations were analyzed from different organs/tissues of two animals found dead floating on the water of the Rio Negro in the Pantanal, Brazil. The mean mercury concentration ranged from 2.94 to 3.68 microg/g in hair, from 1.52 to 4.3 microg/g in liver, and from 1.11 to 4.59 microg/g in kidney and was 0.17 microg/g in muscle samples. In comparison with other research, there is no evidence of contamination in these animals and mercury concentrations in tissues appeared to be at levels below those associated with toxicity.     

Differences in Methylmercury and Inorganic Mercury Biomagnification in a Tropical Marine Food Web

Methylmercury (MeHg), inorganic mercury (Hg_inorg) and their biomagnification factors (BMF) were evaluated along a non-degraded Brazilian bay food web. Highly significant differences (p < 0.0001) were found between MeHg and Hg_inorg concentrations among all organisms (microplankton, shrimp, fish and dolphin). MeHg increased with increasing trophic position while Hg_inorg did not present the same pattern. BMF values for MeHg were higher than 1 for all trophic interactions from source to consumer, indicating that MeHg was transferred more efficiently and biomagnified over the entire web. Only one BMF exceeding one was observed for Hg_inorg (27) between microplankton and their consumer, planktivorous fish. BMF values for Hg_inorg were significantly different than those found for MeHg (20) at the base of the food web.     

When, how, and what to drink: alcoholism among Indian peoples in the Upper Rio Negro, Brazil

This paper analyzes the development of alcoholism among Indian peoples in the Upper Rio Negro, Amazonas State, Brazil. Based on a comprehensive approach to what, how, and when individuals drink, this ethnography emphasizes the socio-cultural and historical context in which alcohol is consumed and interpretation of the issue by Indian people themselves. The article discusses historical transformations in the forms of drinking and their correlations with the status quo and changes in social standards of living. The article concludes that current forms of alcohol consumption are linked to the behaviors and values emerging on the frontier of interethnic relations and the resignification of the traditional culture, currently experiencing difficulties in offering parameters for action and symbolization of social life by the younger generations as they deal with challenges from the modern world.     

Mercury in Bottom Sediments of the Tropical Rio Marabasco,Its Estuary,and Laguna de Navidad,Mexico

Bulletin of Environmental Contamination and Toxicology -     

Characterization of the Mangrove Oyster, Crassostrea rhizophorae, as a Biomonitor for Mercury in Tropical Estuarine Systems, Northeast Brazil

No abstract available.     

Hair Mercury Speciation as a Function of Gender, Age, and Body Mass Index in Inhabitants of the Negro River Basin, Amazon, Brazil

Human mercury contamination can be monitored through hair analysis of mercury's inorganic and organic form as methylmercury (Me-Hg). Hair total mercury and Me-Hg were studied in a Negro River fish-eating population in relation to age, gender, and body mass index (BMI). This riverbank population eats fish at least twice a day and is exposed to high levels of Me-Hg. Total mercury ranged from 1.51 μg/g to 59.01 μg/g, with only 21% of the sampled population having Hg concentration of less than 10 μg/g hair. The mean percentage of Me-Hg was 71.3% (range 34% to 100%) of the total mercury in hair. No statistically significant differences were found in regard to age groups (children and adults) or BMI. However, women had significantly lower total mercury in hair than men, but the percentage of Me-Hg was not significantly different. Women in fertile age (15–40 years) had hair total mercury ranging from 1.65–32.63 μg/g, and 65% in this subgroup had hair mercury above 10 μg/g hair. The percentage of Me-Hg concentration in hair of this freshwater, fish–eating population is comparable to populations eating ocean fish from different parts of the world and does not seem to be affected by age, gender, and BMI. Received: 8 July 2000/Accepted: 8 November 2000     

Cat-transmitted sporotrichosis, Rio de Janeiro, Brazil

Sporotrichosis is an emerging zoonosis in Rio de Janeiro, Brazil. From 1998 to 2003, 497 humans and 1,056 cats with culture-proven sporotrichosis were studied. A total of 421 patients, 67.4% with a history of a scratch or bite, reported contact with cats that had sporotrichosis.     

Mercury Levels in Muscle of Six Species of Turtles Eaten by People Along the Rio Negro of the Amazon Basin

Mercury levels in the Amazon River are generally high, but there are no published studies on Hg levels in turtles from the region. In this study, levels of Hg were examined in the muscle of six species of turtles in the Rio Negro in the Amazon basin of Brazil, including Podocnemis unifilis, Podocnemis expansa, Podocnemis erythrocephala, Podocnemis sextuberculata, Peltocephalus dumerilianus, and Chelus fimbriatus. It is important to analyze Hg levels in chelonians in this region because of the potential health risk to humans and other receptors that eat them, as well as their potential use as bioindicators. The effect of sex, weight, and carapace length on Hg concentrations in turtle muscle was examined to determine if the levels represent a health risk to riverine people. There was a significant interspecific difference in Hg levels but no differences as a function of size or gender. The highest Hg level was found in Chelus fimbriatus (mean = 432 ppb, standard deviation ± 196 ppb), followed by Peltocephalus dumerilianus (106 ± 41 ppb), Podocnemis expansa (62 ± 49 ppb), P. sextuberculata (61 ± 40 ppb), P. unilifis (35 ± 17 ppb), and P. erythrocephala (33.1 ± 17 ppb). Of the species studied, the piscivorous C. fimbriatus had the highest Hg level. Hg levels in turtles were similar to the levels found in fish from the same basin. Levels of Hg in the muscle of C. fimbriatus are sufficiently high to pose a potential risk to humans who consume them. This study represents the first comparative study of Hg levels in muscle of six species of turtles.     

Mercury Biomagnification in the Aquaculture Pond Ecosystem in the Pearl River Delta

This is the first study to investigate the rate of mercury (Hg) biomagnification in the aquaculture pond ecosystem of the Pearl River Delta (PRD), China, by analyzing total mercury (THg) and methyl mercury (MeHg) concentrations in various species of fish at different trophic levels (TLs). Species representing a gradient of trophic positions in the aquaculture pond food chains were chosen for analyzing THg and MeHg concentrations. In this study, there were two kinds of the aquaculture pond food chains: (1) omnivorous (fish feeds, zooplankton, grass carp [Ctenopharyngodon idellus], and bighead carp [Aristichthys nobilis]) and (2) predatory (zooplankton, mud carp [Cirrhina molitorella], and mandarin fish [Siniperca kneri]). Bighead carp and mandarin fish had the highest MeHg and THg concentrations, i.e., an order of magnitude higher than other species, in their respective food chains. More than 90% of the THg concentrations detected in bighead carp, mandarin fish, and mud carp were in the methylated form. In this study, %MeHg increased with TLs and MeHg concentrations, reflecting that MeHg is the dominant chemical species of Hg accumulated in higher concentrations in biota, especially biota associated with higher TLs in the food chains. The trophic magnification factors were 2.32 and 2.60 for MeHg and 1.94 and 2.03 for THg in omnivorous and predatory food chains, respectively, in PRD. Hg concentrations in fish tissue correlated to Hg levels in the ambient environment, and sediment seemed to be the major source for Hg accumulated in fish. In addition, feeding habit also affected Hg accumulation in different fish species. Four significant linear relationships were obtained between log-THg and δ¹⁵N and between log-MeHg and δ¹⁵N. The slope of the regression equations, as biomagnification power, was smaller in magnitude compared with those reported for temperate and arctic marine and freshwater ecosystems, indicating that THg and MeHg biomagnifications were lower in this PRD subtropical aquaculture pond ecosystem. This was probably due to low Hg bioavailability at lower TLs as well as individual feeding behavior of fish.     

HIV vaccine evaluation center in Rio de Janeiro, Brazil

We conducted an HIV seroincidence study among high-risk men who have sex with men in Rio de Janeiro to determine whether this population would be suitable for vaccine and non-vaccine HIV prevention studies. There were 34 HIV seroconversions during the follow-up period, for a seroincidence of 3.1 per 100 person-years. The incidence among the youngest members of our cohort was over 8%, an extraordinarily high transmission rate for a homosexual male population. We have used the sensitive/less sensitive ELISA assay to identify a high-risk heterosexual population for intervention studies in Brazil. The estimated seroincidence was 1.9 and 2.8 per 100 person-years among heterosexual females and males, respectively. We are presently conducting a study to investigate behavior changes among 202 participants of a post-sexual-exposure chemoprophylaxis (PEP) study. During a median follow-up of 24 months, there were 11 HIV seroconversions, 10 of which were among non-PEP users. Additionally, we are conducting a phase 2 HIV vaccine trial of the ALVAC-HIV vector vCP1452 alone and in combination with a subunit vaccine, MN rgp120, in healthy adult volunteers. The primary goal of this trial is to define the immunogenicity and confirm the safety of the most promising vector-based vaccine alone and in combination with a recombinant envelope protein vaccine with an established safety and immunogenicity profile. A phase 3 HIV vaccine trial is planned to begin in the next 18-24 months.     

Neonatal screening for hemoglobinopathies in Rio de Janeiro, Brazil]

OBJECTIVE: To describe the main results obtained in the first 15 months of neonatal screening for sickle cell disease in the state of Rio de Janeiro, Brazil, from August 2000 to November 2001. METHODS: Starting in August 2000, blood samples began to be collected for sickle cell disease screening from all newborns receiving care in primary health care clinics in the state of Rio de Janeiro. The samples were submitted to high-resolution liquid chromatography. If the resulting chromatogram was compatible with sickle cell disease, the child and the parents were referred for diagnostic confirmation and treatment. RESULTS: Between August 2000 and November 2001, 99 260 newborns were screened. There was one case of homozygous Hb C. On average, one of every 27 newborns who were screened presented sickle cell trait (Hb AS). Sickle cell disease was observed in 83 cases, or one new case in each 1 196 births. The 83 consisted of: 62 Hb S, 18 Hb SC, and 3 Hb SD. One child did not appear for diagnostic confirmation. The 82 children who were followed up by the program presented 15 intercurrent illnesses (upper respiratory infections, fever, splenic sequestration crises, hand-foot syndrome, and vascular occlusion), resulting in seven hospital admissions. Blood transfusions were necessary with 15 children, but none developed alloimmunization. All the other babies were doing well with the use of prophylactic penicillin. CONCLUSIONS: Our data show the importance of early diagnosis for sickle cell disease, so as to prevent the frequent infectious complications faced by these patients.     

Food consumption by pregnant adolescents in Rio de Janeiro, Brazil

The increase in teenage pregnancy has been viewed with concern by public health experts. Food consumption to help maintain high nutrient demands has been identified as one of the most relevant components. This study aims to present the habitual consumption of food and energy-specific nutrients by pregnant adolescents. A total of 1,180 adolescent mothers were interviewed in maternity hospitals in the City of Rio de Janeiro, and a simplified questionnaire on semi-quantitative frequency of food consumption was applied. Lower consumption of fruit juice, vegetables, and fruits was observed among adolescent mothers over 15. Adolescent mothers classified in the lowest quartile of consumption lack the minimum recommended consumption of energy and nutrients. An inverse association was found between the number of household members and energy and nutrient consumption. Adolescent mothers who received dietary information and changed their eating habits during pregnancy showed better results concerning the consumption of energy and nutrients. Prenatal care was a key factor for improving the results of pregnancy, emphasizing the importance of providing dietary information.     

Factors associated with cesarean sections in a public hospital in Rio de Janeiro, Brazil

Brazil has one of the world's highest cesarean section rates. Contributing factors include the organization of obstetric practice, physicians' attitudes, and women's preferences and decisions. This study aimed to identify factors associated with cesarean sections in a public maternity hospital in Rio de Janeiro. A case-control study was conducted with 231 cesarean sections (cases) and 230 vaginal deliveries (controls). Hierarchical logistic regression analysis was performed, based on a conceptual model. Factors associated with increased odds of cesarean section were: primiparity; mother's age 20-34; last birth by cesarean; cervical dilatation < 3cm at admission; patient request; daytime birth; male attending obstetrician; obstetrician on duty for more than 24 hours a week; obstetrician with private practice; gestational hypertension; non-cephalic presentation; and gestational age > 41 weeks. Factors associated with lower odds of cesarean were: gestational age < 37 weeks; leaving home with signs of labor, use of oxytocin; and amniotomy. In this hospital, interventions aimed to modify the above-mentioned factors can help lower the cesarean rate.