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BACKGROUND: Nickel is a ubiquitous element used in many everyday items. In recent decades nickel has become a leading allergen, which has become a public health problem. OBJECTIVE: To evaluate frequently used nickel products in Brazil. We investigated if these objects release nickel that is capable of inducing sensitization or cause clinical manifestations in terms of allergic contact dermatitis (ACD). METHODS: Dimethylglyoxime (DMG) spot tests assessed nickel release from several common utensils used in everyday life in São Paulo and Rio de Janeiro, Brazil. RESULTS: We tested 46 coins (two denominations) and 90 common utensils. Approximately 91.1% produced nickel-positive results using the DMG spot test. CONCLUSIONS: The DMG limit of detection was 1.67 ppm of nickel. We observed that many objects in our test series released nickel above the DMG test limit. This observation suggests that nickel-sensitive individuals may be exposed to nickel, representing a public health issue.

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With regards to health, chromium (Cr) is an ambiguous chemical element. Although it is considered to be an important micronutrient, it also is connected with several pathologies, including carcinogenicity. The mechanism of action of Cr and its compounds in humans is not yet fully understood. Currently, three possible mechanisms have been proposed for carcinogenesis: Cr(VI)-induced multistage carcinogenesis, genomic instability, and epigenetic modification. Therefore, in addition to the toxicity of this metal and its ions, human susceptibility to Cr-induced pathologies depends on external factors and individual characteristics, such as enzymatic polymorphisms, carriers, endogenous reducing system, adduct formation and stability, and efficiency of DNA repair mechanisms, among other factors. In fact, the variability of individual molecular constitutive factors, such as individual polymorphisms, creates an individualized environment for Cr toxicity. This mini-review contemplates the essential variables in this process.

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The Indigo carmine (IC) dye has been widely used in textile industries, even though it has been considered toxic for rats, pigs and humans. Owing to its toxicity, wastes containing this compound should be treated to minimize or eliminate their toxic effects on the biota. As an alternative to wastewater treatment, advanced oxidative processes (AOPs) have been highlighted due to their high capacity to destruct organic molecules. In this context, this study aimed to evaluate Indigo Carmine toxicity to soil organisms using the earthworm Eisenia andrei as a model-organism and also verify the efficiency of AOP in reducing its toxicity to these organisms. To this end, lethal (mortality) and sub-lethal (loss or gain of biomass, reproduction, behavior, morphological changes and immune system cells) effects caused by this substance and its degradation products in these annelids were evaluated. Morphological changes were observed even in organisms exposed to low concentrations, while mortality was the major effect observed in individuals exposed to high levels of indigo carmine dye. The organisms exposed to the IC during the contact test showed mortality after 72h of exposure (LC50 = 75.79mgcm-2), while those exposed to photoproducts showed mortality after 48h (LC50 = 243min). In the chronic study, the organisms displayed a mortality rate of 14%, while those exposed to the photoproduct reached up to 32.7%. A negative influence of the dye on the reproduction rate was observed, while by-products affected juvenile survival. A loss of viability and alterations in the cellular proportion was verified during the chronic test. However, the compounds did not alter the behavior of the annelids in the leak test (RL ranged from 20% to 30%). Although photocatalysis has been presented as an alternative technology for the treatment of waste containing the indigo carmine dye, this process produced byproducts even more toxic than the original compounds to E. andrei.

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The objective of this study was to evaluate the burden of environmental pollution by Polychlorinated Biphenyls (PCBs) and Organochlorine Pesticides (OCs) in two localities of Rio de Janeiro coast, through the determination of these levels in specimens of mullets and croakers collected from May to August 2008, at Guanabara Bay (GB) and from Araújo Island (AI), at Paraty Bay. Twenty three organochlorine pollutants were detected in croakers at GB and twenty in mullets and all PCBs congeners investigated in the study were present in the two species. Ratio ∑DDT/∑PCB of 1.4 shows an important contribution of agricultural residues in GB and p,p'-DDE/∑DDT of 0.1 demonstrates a reintroduction of DDT. Consumption of mullet may represent a risk to the health of fishermen families from GB, with average and maximum estimated daily intake of ∑DDT of 9.012µg/kg p.c. and 26,174µg/kg p.c., representing 45% and 131% of ADI established by WHO.

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O uso indiscriminado de um número cada vez maior de substâncias químicas vem aumentando e a contaminação ambiental associada tem trazido sérias consequências para o sistema público de saúde devido à elevação de danos para a saúde humana. Uma das substâncias que desperta grande interesse devido à contaminação contemporânea é o benzeno, composto aromático classificado pela International Agency for Research on Cancer como reconhecidamente carcinogênico para humanos. O objetivo do presente estudo foi elaborar e discutir um panorama sobre a contaminação por benzeno, seu metabolismo, consequências para a saúde e sua determinação ambiental e biológica a partir de informações existentes na literatura científica. O levantamento de dados possibilitou o acesso a mais de 200 artigos científicos tanto de âmbito nacional quanto internacional, demonstrando a atualidade do tema e a necessidade de minimização da exposição humana a essa substância. A maioria preocupa-se em explorar o metabolismo e investigar indicadores de exposição, muitos já amplamente estudados e com sérias limitações. Contudo, um crescente número de pesquisadores estão empenhados em elucidar fatores relacionados à suscetibilidade e à interferência da exposição no material genético e proteico. Indicadores de exposição inovadores têm sido propostos com o objetivo de complementar as lacunas de informações anteriormente obtidas, contribuindo para o delineamento da estrutura da biologia de sistemas orgânicos frente à exposição ao benzeno.

The indiscriminate use of an increasing number of chemicals is growing and associated environmental contamination has brought serious consequences for the public health system due to rising damage to human health. One of the substances that have attracted great interest due to contemporary contamination is benzene, aromatic compound classified by International Agency for Research on Cancer as a carcinogen known. The aim of this study was develop and discuss an overview of the contamination by benzene, its metabolism, health endings and their environmental and biological determination based on literature data existing. The survey provided access to more than 200 scientific papers, both nationally and internationally, demonstrating the relevance of the topic and the need to minimize human exposure to this substance. The majority is concerned with exploring the metabolism and investigates indicators of exposure, many already widely studied and with serious limitations. However, a growing number of researchers are committed to elucidate factors related to interference susceptibility and exposure on protein and genetic material. Indicators of innovative exhibition has been proposed with the aim of complementing gaps of information previously obtained, contributing to the design of the structure of the organ biology systems upon exposure to benzene.

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Photocatalytic degradation of bisphenol A (BPA) in waters and wastewaters in the presence of titanium dioxide (TiO2) was performed under different conditions. Suspensions of the TiO2 were used to compare the degradation efficiency of BPA (20 mg L(-1)) in batch and compound parabolic collector (CPC) reactors. A TiO2 catalyst supported on glass spheres was prepared (sol-gel method) and used in a CPC solar pilot plant for the photodegradation of BPA (100 µg L(-1)). The influence of OH·, O2 (·-), and h (+) on the BPA degradation were evaluated. The radicals OH· and O2 (·-) were proved to be the main species involved on BPA photodegradation. Total organic carbon (TOC) and carboxylic acids were determined to evaluate the BPA mineralization during the photodegradation process. Some toxicological effects of BPA and its photoproducts on Eisenia andrei earthworms were evaluated. The results show that the optimal concentration of suspended TiO2 to degrade BPA in batch or CPC reactors was 0.1 g L(-1). According to biological tests, the BPA LC50 in 24 h for E. andrei was of 1.7 × 10(-2) mg cm(-2). The photocatalytic degradation of BPA mediated by TiO2 supported on glass spheres suffered strong influence of the water matrix. On real municipal wastewater treatment plant (MWWTP) secondary effluent, 30 % of BPA remains in solution; nevertheless, the method has the enormous advantage since it eliminates the need of catalyst removal step, reducing the cost of treatment.

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OBJECTIVE: The aim of the study was quantify organochlorine compounds in women seeking for infertility treatment (n = 15) and in spontaneously pregnant ones (n = 21). MATERIALS AND METHODS: A questionnaire was applied regarding lifestyle, occupational and reproductive history. Blood samples were collected from both groups. RESULTS: From the pesticides studied, pp'DDE was detected in 100% of infertile women, at higher mean levels than in pregnant women (3.02 mcg/L vs. 0.88 mcg/L; p = 0.001; power of 69%), without correlation with the etiology of infertility. Levels of the polychlorinated biphenyls (PCBs) were low, with positive samples in 100% in the infertile women for PCBs 138, 153, 180, while in pregnant women, they were 85.7% for congeners 138 and 153. Only PCB180 showed significance, with frequency of 71.4% (p = 0.019). CONCLUSIONS: The risk factors for female infertility were: age, consumption of untreated water and of canned foods. Exposure to the most prevalent organochlorine compounds described in literature was confirmed in the study, indicating that pp'DDE may adversely influence female fertility.

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OBJECTIVE: The aim of the study was quantify organochlorine compounds in women seeking for infertility treatment (n = 15) and in spontaneously pregnant ones (n = 21). MATERIALS AND METHODS: A questionnaire was applied regarding lifestyle, occupational and reproductive history. Blood samples were collected from both groups. RESULTS: From the pesticides studied, pp'DDE was detected in 100% of infertile women, at higher mean levels than in pregnant women (3.02 mcg/L vs. 0.88 mcg/L; p = 0.001; power of 69%), without correlation with the etiology of infertility. Levels of the polychlorinated biphenyls (PCBs) were low, with positive samples in 100% in the infertile women for PCBs 138, 153, 180, while in pregnant women, they were 85.7% for congeners 138 and 153. Only PCB180 showed significance, with frequency of 71.4% (p = 0.019). CONCLUSIONS: The risk factors for female infertility were: age, consumption of untreated water and of canned foods. Exposure to the most prevalent organochlorine compounds described in literature was confirmed in the study, indicating that pp'DDE may adversely influence female fertility.

OBJETIVO: O estudo teve como objetivo quantificar as substâncias organocloradas em mulheres buscando tratamento para infertilidade (n = 15) e que espontaneamente engravidaram (n = 21). MATERIAIS E MÉTODOS: Foi aplicado questionário considerando estilo de vida, história ocupacional e reprodutiva. Amostras de sangue foram obtidas em ambos os grupos. RESULTADOS: Dos pesticidas, pp'DDE foi detectado em 100% das inférteis, com níveis maiores que nas grávidas (3,02 mcg/L vs. 0,88 mcg/L; p = 0,001; poder 69%), sem correlação na etiologia da infertilidade. Os níveis de detecção das bifenilas policloradas (PCBs) foram baixos, com 100% de positividade das amostras nas inférteis para os PCBs 138, 153, 180, e de 85,7% nas grávidas para os congêneres 138 e 153. Apenas PCB180 mostrou significância na frequência de 71,4% (p = 0,019). CONCLUSÕES: Os fatores de risco para infertilidade feminina foram: idade, consumo de água não tratada e alimentos enlatados. A exposição aos organoclorados mais prevalentes descritos na literatura foi confirmada no estudo, indicando que pp'DDE pode influenciar adversamente a fertilidade feminina.

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The photocatalytic degradation of two commercial textile azo dyes, namely C.I Reactive Black 5 and C.I Reactive Red 239, has been studied. TiO(2) P25 Degussa was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO(2) used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated and we observed that the degradation rates achieved in mono and bi-component systems were identical. The repeatability of photocatalytic activity of the photocatalyst was also tested. After five cycles of TiO(2) reuse the rate of colour lost was still 77% of the initial rate. The degradation was followed monitoring the change of azo dye concentration by UV-Vis spectroscopy. Results show that the use of an efficient photocatalyst and the adequate selection of optimal operational parameters may easily lead to a complete decolorization of the aqueous solutions of both azo dyes.

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This work describes an efficient, fast, and reliable analytical methodology for mercury determination in urine samples using stripping chronopotentiometry at gold film electrodes. The samples were sonicated in the presence of concentrated HC1 and H2O2 for 15 min in order to disrupt the organic ligands and release the mercury. Thirty samples can be treated over the optimized region of the ultrasonic bath. This sample preparation was enough to allow the accurate stripping chronopotentiometric determination of mercury in the treated samples. No background currents and no passivation of the gold film electrode due to the sample matrix were verified. The samples were also analyzed by cold vapour atomic absorption spectrometry (CV-AAS) and good agreement between the results was verified. The analysis of NIST SRM 2670 (Toxic Metals in Freeze-Dried Urine) also validated the proposed electroanalytical method. Finally, this method was applied for mercury evaluation in urine of workers exposed to hospital waste incinerators.