ABSTRACT Adélie penguins (Pygoscelis adeliae) are seabirds that live exclusively in Antarctica, one of the planet's last pristine areas. However, this remote region is experiencing a continuing expansion of human activities that may affect Antarctic fauna. Trace metals constitute a menace to seabirds because they can adversely affect their health. There is a lack of studies relating to metals' levels in feathers with morphological parameters of seabirds. Trace metal levels were measured in Adélie penguin feathers and their body condition through the relative condition factor (ReCF) in adult individuals from two South Shetland Islands locations and two from Graham Land. Consequently, we determined the levels of some metals in feathers to see any relationship with morphological parameters linked to the bird's health. Our results showed significant differences in metals among locations studied and a significant relationship between ReCF with Cu and Zn in one of the South Shetland Islands. Also, penguins exhibited a significantly lower weight. We found a positive correlation between non-essential with essential metals, indicating that Cu acts as a detoxifying agent for Cr, Cd, and Pb. In contrast, Se could be for V and Pb. Although the relationship between most metals with ReCF was not significant, some site-specific factors may be influencing it, whereas metals may be affecting the organisms at low biological levels. Molecular, biochemical, and genetic studies are required to elucidate this issue.

RESUMO Este é o primeiro estudo a investigar a contaminação por mercúrio (Hg) em espécies de felinos na Amazônia brasileira. Foram coletadas 26 amostras de pelo de felinos selvagens de quatro espécies (Puma concolor, Panthera onca, Leopardus pardalis e Leopardus wiedii) ocorrendo nas reservas de desenvolvimento sustentável Mamirauá e Amanã, no estado do Amazonas. As amostras foram coletadas de espécimes de museu, exceto cinco amostras de P. onca obtidas de indivíduos capturados em vida livre. As concentrações de Hg variaram de 0,12 a 48,1 µg g-1. Não houve diferença significativa entre a concentração de Hg no pelo de espécimes de museu e de indivíduos vivos de P. onca. Houve variação significativa entre espécies, sendo que P. onca e L. pardalis tiveram concentrações significativamente mais altas, o que pode estar relacionado a fatores como dieta e hábitat.

ABSTRACT This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors such as diet and habitat.

Abstract Nanocomposite based on high density polyethylene (HDPE) and layered zirconium phosphate organically modified with octadecylamine (ZrPOct) was obtained through melt processing. The ZrPOct was synthesized by precipitation and modified by suspension and sonication procedures. The initial and maximum degradation temperatures (Tonset and Tmax) were increased. A slight decrease of crystallinity degree was detected. Reduction of elastic modulus and elongation at break were noticed. The lamellar spacing was increased (3.3 times higher). The storage modulus decreased and low field nuclear magnetic resonance (LFNMR) revealed an increasing of molecular mobility. The presence of octadecylamine enhanced the entrance of HDPE in the ZrPOct galleries. Several characteristics of HDPE were changed indicating that intercalation was successful. All results indicated that partially intercalated and/or exfoliated nanocomposite was achieved.

Knowing the mercury levels of an environment allows a diverse array of biogeochemical studies into the mercury cycle on a local or global scale. Among matrices commonly evaluated, water remains a challenge for research because its mercury levels can be very low, requiring development of complex analytical protocols. Currently, sample preservation methods, protocols that avoid contamination, and analytical techniques with low detection limits allow analysis of mercury in pristine waters. However, different protocols suggest different methods depending on a range of factors such as the characteristics of water sampled and storage time. In remote areas, such as oceanic and Amazonian regions, sample preservation and transport to a laboratory can be difficult, requiring processing of the water during the sampling expedition and the establishment of a field laboratory. Brazilian research on mercury in water can be limited due to difficulty obtaining reagents, lack of laboratory structure, qualified personnel, and financial support. Considering this complexity for analyzing water, we reviewed methodologies for sampling, preservation, and storage of water samples for analysis of the most commonly evaluated mercury species (dissolved gaseous mercury, reactive mercury, methylmercury and total mercury).

Introdução: Pacientes com Doença Renal Crônica apresentam deficiência de selênio (Se), um elemento essencial, com importantes funções biológicas, como a de ser componente da enzima antioxidante glutationa peroxidase (GPx). A concentração de Se nos alimentos depende de sua concentração no solo e autores relatam que o solo da Amazônia possui elevados níveis de Se. Objetivo: O objetivo do trabalho foi comparar o estado nutricional do Se em pacientes em hemodiálise (HD) das regiões Norte e Sudeste do Brasil. Métodos: Trinta e oito pacientes da região Sudeste (22 homens e 16 mulheres, 15% diabéticos, 53,5 ± 26,4 anos) foram comparados com 40 pacientes da região Norte (28 homens e 12 mulheres, 22,5% diabéticos, 63,5 ± 11,9 anos). O Se no plasma foi determinado por espectrofotometria de absorção atômica por geração de hidretos acoplados a cela de quartzo. Resultados: Os níveis de Se dos pacientes em HD da região Sudeste foram significativamente menores (17,5 ± 11,9 μg/L) comparados aos pacientes da região Norte (37,1 ± 15,8 μg/L) (p < 0,001). Entretanto, ambos os grupos apresentaram níveis de Se abaixo da recomendação (60-120 μg/L). Não houve associação entre os níveis de Se e os parâmetros analisados. Conclusão: Com base nos resultados, concluímos que os pacientes da região Norte apresentaram elevados níveis de Se quando comparados com os pacientes da região Sudeste do Brasil. Entretanto, independentemente da região, ambos os grupos apresentaram deficiência com relação ao estado nutricional do Se.

Introduction: Patients with chronic kidney disease present selenium (Se) plasma deficiency which is an essential trace element with important biological functions and, the best known biological role is attributed to its presence in the antioxidant enzyme, glutathione peroxidase (GPx). The Se content of foods depends on soil and some authors have suggested that Amazon soil (North Brazilian region) has high Se concentrations when compared to other regions of Brazil. Objective: The objective of this work was to compare the Se status in hemodialysis (HD) patients from North and Southeast of Brazil. Methods: Thirty-eight patients from Southeast region (22 men and 16 women, 15% diabetic, 53.5 ± 26.4 yrs) were compared to 40 patients from North region (28 men and 12 women, 22.5% diabetic, 63.5 ± 11.9 yrs). Se in plasma was determined through atomic absorption spectrophotometry with hydride generation. Results: The plasma Se levels in patients from Southeast region were significantly lower (17.5 ± 11.9 μg/L) when compared to patients from the North (37.1 ± 15.8 μg/L) (p < 0.001). However, both patient groups presented low Se plasma levels when compared to recommended values (60- 120 μg/L). There was no correlation between plasma Se levels and analyzed parameters. Conclusion: We concluded that patients from North (Amazon) region present higher plasma Se levels when compared to the patients from Southeast of Brazil. However, independently of the region, HD patients presented Se deficiency.

Um método simples, validado e econômico está descrito para a determinação de deltametrina e cipermetrina em leite bovino. Baseia-se na extração simultânea e clean up da matriz por dispersão em fase sólida (MSPD) com Celite® usando hexano/acetona (7:3 v/v), seguido de análise por cromatografia gasosa com detecção por captura de elétrons (GC-µECD). A análise de confirmação foi feita por GC-espectrometria de massas (MS). O processo simultâneo mostrou-se eficiente para amostras de leite. As recuperações médias em amostras de leite bovino fortificadas ficaram na faixa de 60 a 81%, com um desvio-padrão relativo (RSD) de 9 a 18%. O método apresentou limites de quantificação (LOQ) de 0,010 µg g-1 para ambos os piretróides e os limites de detecção (LOD) foram 0,007 e 0,002 µg g-1 para cipermetrina e deltametrina, respectivamente. A principal vantagem do método proposto é o número reduzido de etapas envolvidas, além de ser simples, rápido e barato. O método foi aplicado em amostras de leite integral coletadas em propriedades leiteiras do município de Chapada dos Guimarães, MT, Brasil. Deltametrina não foi detectada nas vinte amostras analisadas e cipermetrina foi detectado em quatro amostras (20%) em quantidades inferiores ao limite de quantificação.

A simple, validated and economic method is described for the determination of deltamethrin and cypermethrin in bovine milk. It is based on simultaneous extraction and clean up on matrix solid-phase dispersion (MSPD) with Celite® using hexane/acetone (7:3 v/v), followed by gas chromatography with electron capture detector (GC-µECD) analysis. Confirmatory analysis was carried out by GC-mass spectrometry (MS). The simultaneous process showed to be efficient for milk samples. Average recoveries from fortified bovine milk samples were in the range of 60 to 81%, with relative standard deviation (RSD) from 9 to 18%. Method limits of quantification (LOQ) were 0.010 µg g-1 for both pyrethroids and limits of detection (LOD) were 0.007 and 0.002 µg g-1 for cypermethrin and deltamethrin, respectively. The main advantage of the proposed method is the reduced number of steps involved, besides being simple, rapid and inexpensive. The method was applied to whole milk samples collected at dairy farms in the municipality of Chapada dos Guimarães, MT, Brazil. Deltamethrin was not detected in the twenty analyzed samples, and cypermethrin was detected in four samples (20%) at trace levels (< LOQ).

Neste estudo Da exposição humana e ambiental ao Manganês (Mn) no Sul do Brasil foi realizada em duas etapas. O primeiro passo consistiu na análise de amostras de águas da superfície do rio Pardinho. Os resultados médios desta tecnica mostraram aumento significativo de poluentes, incluindo aumento dos níveis de Mn acima do padrão aceitável para o ambiente recomendado pelo Conselho Nacional de Meio Ambiente. Além disso, 64 amostras de solo foram coletadas em áreas com e sem atividade agrícola. Muitos resultados ficaram acima da média e não indicaram diferenças significativas dos níveis de Mn entre as áreas amostradas. Para o segundo passo, 12 famílias foram selecionadas e avaliadas quanto à exposição ao Manganês nas regiões com níveis elevados de Mn no solo. A maioria dos alimentos analisados continham Mn acima dos valores de referência, indicando que o alimento pode ser uma fonte importante de exposição. O teor de Mn no cabelo da maioria dos indivíduos estudados foi também elevado em comparação com valores de referência de populações não-expostas. Apesar de a contaminação parecer vir de uma origem natural, os resultados encontrados neste estudo mostraram que os níveis de Mn presentes na Bacia do Rio Pardinho são um relevante problema de saúde pública.

The study of environmental pathways and human exposure to Manganese (Mn) in Southern Brazil was performed using two steps. The first step consisted of taking water samples from the surface of the Pardinho River. The average results from this technique showed a significant increase of pollutants, including increased levels of Mn, above the environmentally acceptable standard recommended by the Brazilian National Environment Council. Additionally, 64 soil samples were taken from areas with and without agricultural activity. Many results were above the mean crust and did not indicate significant differences of Mn levels between the sampled areas. For the second step, 12 families were selected and assessed for exposure to Mn in a region with high levels of Mn in the soil. Most of the analyzed foods contained amounts of Mn above the reference values, indicating that food can be an important source of exposure. The Mn content from the hair of most subjects studied was also high compared to reference values from non-exposed populations. Although the contamination appeared to come from a natural origin, the results found in the present study showed that the Mn levels present in the Pardinho River Basin are a relevant public health issue.

O mercúrio é neurotóxico e muitas pesquisas confirmam sua ação ototóxica. Porém, para o diagnóstico e acompanhamento da exposição é necessário entender a fisiopatologia da substância química. O objetivo do trabalho, por meio da revisão sistemática, é evidenciar se o mercúrio é ou não ototóxico e, sendo assim, qual seria sua forma de atuação no sistema auditivo periférico e central, de forma a contribuir para o diagnóstico e acompanhamento da exposição. É uma revisão sistemática dos trabalhos publicados sobre os efeitos da exposição ao mercúrio no sistema auditivo. Analisaram-se os estudos contemplados na íntegra e também sua qualidade metodológica. A pesquisa identificou 108 artigos publicados sobre o tema, sendo que 28 se enquadraram nos critérios de inclusão. Todos os artigos analisados evidenciaram que a exposição ao mercúrio é ototóxico e induz ao dano periférico e/ou central. A exposição aguda e de longo prazo produzem danos irreversíveis ao sistema auditivo central. Os biomarcadores não puderam predizer a relação do grau de intoxicação com o grau de lesão do sistema auditivo.

Mercury is neurotoxic, and numerous studies have confirmed its ototoxic effect. However, the diagnosis and follow-up of mercury exposure require understanding the pathophysiology of the chemical substance. Based on a systematic literature review, this study aimed to demonstrate whether mercury is ototoxic and to analyze its mechanism of action on the peripheral and central auditory system, in order to contribute to the diagnosis and follow-up of exposure. This was a systematic review of studies published on the effects of mercury exposure on the auditory system. The full text of the studies and their methodological quality were analyzed. The review identified 108 studies published on the theme, of which 28 met the inclusion criteria. All the articles in the analysis showed that mercury exposure is ototoxic and produces peripheral and/or central damage. Acute and long-term exposure produces irreversible damage to the central auditory system. Biomarkers were unable to predict the relationship between degree of mercury poisoning and degree of lesion in the auditory system.

O mercúrio é neurotóxico e muitas pesquisas confirmam sua ação ototóxica. Porém, para o diagnóstico e acompanhamento da exposição é necessário entender a fisiopatologia da substância química. O objetivo do trabalho, por meio da revisão sistemática, é evidenciar se o mercúrio é ou não ototóxico e, sendo assim, qual seria sua forma de atuação no sistema auditivo periférico e central, de forma a contribuir para o diagnóstico e acompanhamento da exposição. É uma revisão sistemática dos trabalhos publicados sobre os efeitos da exposição ao mercúrio no sistema auditivo. Analisaram-se os estudos contemplados na íntegra e também sua qualidade metodológica. A pesquisa identificou 108 artigos publicados sobre o tema, sendo que 28 se enquadraram nos critérios de inclusão. Todos os artigos analisados evidenciaram que a exposição ao mercúrio é ototóxico e induz ao dano periférico e/ou central. A exposição aguda e de longo prazo produzem danos irreversíveis ao sistema auditivo central. Os biomarcadores não puderam predizer a relação do grau de intoxicação com o grau de lesão do sistema auditivo.

Mercury is neurotoxic, and numerous studies have confirmed its ototoxic effect. However, the diagnosis and follow-up of mercury exposure require understanding the pathophysiology of the chemical substance. Based on a systematic literature review, this study aimed to demonstrate whether mercury is ototoxic and to analyze its mechanism of action on the peripheral and central auditory system, in order to contribute to the diagnosis and follow-up of exposure. This was a systematic review of studies published on the effects of mercury exposure on the auditory system. The full text of the studies and their methodological quality were analyzed. The review identified 108 studies published on the theme, of which 28 met the inclusion criteria. All the articles in the analysis showed that mercury exposure is ototoxic and produces peripheral and/or central damage. Acute and long-term exposure produces irreversible damage to the central auditory system. Biomarkers were unable to predict the relationship between degree of mercury poisoning and degree of lesion in the auditory system.

Mercúrio e selênio foram determinados no tecido muscular do peixe espada (Trichiurus lepturus) de três áreas costeiras (Baía da Ilha Grande, Baía de Guanabara and Búzios, Estado do Rio de Janeiro) que apresentam diferentes condições ambientais, localizadas no sudeste brasileiro. Hg foi determinado por espectrometria de absorção atômica em vapor frio (CV-AAS) e Se por espectrometria de absorção atômica com forno de grafite (GF-AAS). As concentrações variaram de 0,44 a 0,87 µg Hg g-1 e de 0,0050 a 3,12 µg Se g-1, em peso seco. Foram observadas diferenças significativas na concentração de mercúrio e na razão molar selênio:mercúrio entre as áreas. O comprimento total e os intervalos de tamanho influenciaram na acumulação de mercúrio, entretanto estes parâmetros biológicos não influenciaram na acumulação de selênio. Foi observado um excesso de selênio em relação ao mercúrio. Provavelmente, as diferenças regionais podem ser em parte atribuídas às diferenças nas condições ambientais (temperatura da água e produção primária), e também a outros fatores, tais como a escolha das presas e a disponibilidade destes elementos nos ambientes.

Mercury and selenium were assessed in the muscle tissue of cutlassfish (Trichiurus lepturus) from three coastal areas (Ilha Grande Bay, Guanabara Bay and Búzios coast, Rio de Janeiro State, Brazil) that present different environmental conditions, localized in Southeastern Brazil. Hg was determined by cold vapor atomic absorption spectrometry (CV-AAS) and Se was determined by graphite furnace atomic absorption spectrometry (GF-AAS). Across sites, mercury and selenium in this fish ranged from 0.44 to 0.87 µg Hg g-1 and 0.0050 to 3.12 µg Se g-1 dry wt. Significant differences were observed in mercury concentrations and Se:Hg molar ratios among the areas. The total length and size intervals presented a significant influence on the accumulation of mercury, whereas this pattern was not observed for selenium. A large excess of selenium in relation to mercury was observed. Probably, the regional differences can be partly attributed to differences in the prevalent environmental conditions (water temperature and primary production), and also to other factors, such as prey choices and availability across locations.

O estuário do rio Goiana (7º30'S 34º47'W) é um típico estuário de região tropical semi-árida. Esse estuário abriga uma fauna rica de peixes, crustáceos e moluscos que tem um importante papel na vida da população tradicional. Ele também é o principal receptor de efluentes da agroindústria da cana-de-açúcar e esgoto das comunidades e vilas. Trichiurus lepturus (n = 104), do estuário do rio Goiana foram examinados para o conteúdo de mercúrio total durante dez meses (2005 a 2007) ao longo de duas estações secas e parte de uma estação chuvosa. Os indivíduos estudados apresentaram peso (P) (204,1±97,9 g) e comprimento total (CT) (63,1±10,1 cm, variação 29,5-89,0 cm) com uma correlação significativa (p<0,05). As correlações entre CT e Hg-T (r = 0,37286) e entre P e Hg-T (r = 0,38212) foram positivas e significativas. AANOVA (2 fatores) (n =81) mostrou que o CT e P apresentaram diferenças significativas (p<0,05) entre as estações. O Hg-T apresentou diferença em relação ao fator estação (p<0,05). A correlação entre Hg-T e a chuva apresentou uma relação negativa e significativa (r = -0,56; p<0,05). A precipitação pluviométrica influenciou fortemente a bioacumulação de mercúrio nessa espécie. Os meses secos apresentaram relativamente concentrações de mercúrio maiores do que o final da estação chuvosa. Isso sugere que a menor precipitação pluviométrica, e consequentemente a menor quantidade de material particulado e menor produtividade primária no estuário, torna o mercúrio mais biodisponível. Peixes desse estuário podem ser consumidos pela população humana ao longo de todo ano.

The Goiana River Estuary (7º30'S 34º47'W) is a typical estuary of the semi-arid tropical regions. This estuary shelters a rich fauna of fish, crustaceans and mollusks which play an important role in the life of traditional populations. It is also the main recipient of the effluents from the sugarcane agro-industry and sewage from settlements and villages. Trichiurus lepturus (n = 104), from the Goiana Estuary were examined for total mercury contents during ten months (2005 to 2007) spaning two dry seasons and part of a rainy season. The studied individuals showed weight (W) (204.1±97.9 g) and total length (TL) (63.1±10.1 cm, range 29.5-89.0 cm) with a significant (p<0.05) correlation. Correlation between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were positive and significant (p<0.05). Two-way ANOVA (n = 81) showed that TL and W had significant difference (p<0.05) among seasons. The Hg-T showed differences in relation to the factor season (p<0.05). The correlation between Hg-T and rainfall showed a negative and significant relation (r = -0.56; p<0.05). Rainfall strongly influenced the bioacumulation of mercury in this species. Dryer months showed relatively higher mercury concentrations than the end of the rainy season. Less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more bioavailable. Fish from this estuary are fit for human consumption at all times of the year.

Methylmercury was determined in water and aquatic biota from Guanabara Bay. Trophic transfer of methylmercury was observed between trophic levels from prey (microplankton, mesoplankton and fish with different feeding habits) to top predator (pelagic demersal fish). Top predator fish presented the highest methylmercury concentrations (320.3 ± 150.7 mg kg-1 dry wt.), whereas microplankton presented the lowest (8.9 ± 3.3 mg kg-1 dry wt.). The successive amplification of methylmercury concentrations and its bioconcentration factor with increasing trophic levels from base to top indicate that biomagnification may be occurring along the food web. Results suggest the importance of feeding habits and trophic level in the bioaccumulation of methylmercury by aquatic biota.

DDT concentrations had been quantified in fishes and at 20 points along the "Puruzinho" lake. The determination of pollutants in the samples consisted in four consecutive steps: extraction, clean-up, fractionation and automatic injection in high resolution gas chromatography coupled to an electron capture detector. The ΣDDT results in fishes (ng g-1 dry weight) ranged from 0.3 to 71.4. The concentrations of ΣDDT on house soils varied from 2.0 to 55.4 ng.g-1 while forest soils the obtained values were between 1.6 e 13.3 ng g-1. The Shapiro-Wilk test showed that the distribution was not normal for both the results of the soil of the houses (p < 0.001) as well as for the forest soils (p < 0.007). The U test of Mann-Whitney reveled that there were no significant difference between the results obtained for both houses and forest soils (p > 0.290).

Trophic transfer of trace elements along marine food chains has been recognized as an important process influencing metal and metalloid bioaccumulation. The trophic transfer of mercury was observed between trophic levels from prey (considering fish with different feeding habits and squid) to top predator (dolphin) in a Northern coastal food chain of Rio de Janeiro. Selenium showed some evidence of trophic transfer between lower trophic levels. Dolphin presented the highest mercury concentrations whereas the benthic carnivorous fish showed the highest selenium concentrations. Mercury is biomagnified through the food chain while selenium does not present the same behavior.