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The most common alternative for the management and valorization of rice processing waste is the combustion of rice husk (RH) for energy generation. The environmental risk assessment of the ash generated during the combustion of the RH to obtain energy has remained understudied. Disposal of rice husk ash (RHA) on agricultural land is the most common outcome, which could pose a risk to both natural ecosystems and human health. The objective of this study was to characterize the physicochemical composition and the phytotoxicity, cytotoxicity, and genotoxicity of RHA obtained from three distinct combustion processes. The evaluation processes were 800-900 °C in up to 5 min (I), 800-900 °C in 15-20 min (II), and 600-700 °C in 15-20 min (III). Furthermore, the content, pH, and concentrations of Al, Cd, Cu, Fe, Mg, Mn, Mo, Na, Ni, and Ti present in the ashes were determined. The germination index for two vegetable seeds was subsequently evaluated. By measuring the mitotic index and frequency of chromosomal aberrations, the cytotoxicity and genotoxicity were determined. It was observed that RHA produced by combustion of RH at higher combustion temperatures for an extended period exhibited different physicochemical properties, in addition to higher levels of phytotoxicity, cytotoxicity, and genotoxicity.

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Inorganic forms of As (arsenite - As(III) and arsenate - As(V)) are prevalent in soil and recognized for their high toxicity. Once in the soil, these forms of As can compromise key organisms for ecological processes, such as earthworms. The aim of the study was to evaluate the toxicity of arsenite and arsenate in the Californian earthworm Eisenia andrei exposed in natural soil and tropical artificial soil (TAS). Adverse effects were evaluated using avoidance test, acute toxicity test, and a sublethal concentration test to assess biochemical parameters. LC50 values for arsenite were 21.27 mg/kg in natural soil and 19.0 mg/kg in TAS and for arsenate were 76.18 mg/kg in natural soil and above 120 mg/kg in TAS. In the avoidance test, this behavior was shown to be significantly higher in the natural soil and for earthworms exposed to arsenite, while total antioxidant capacity, glutathione levels, lipid damage, and DNA damage were significantly higher in animals exposed to arsenite, but without differences in relation to the two types of soil tested. Animals exposed to As(V) showed increased activity of enzymes related to glutathione metabolism. The results obtained in the present study show the impact of As exposure on the health of the Californian earthworm E. andrei, especially in the form of arsenite, and alert the public authorities that legal limits should, whenever possible, consider the soil properties and also the different chemical species of the contaminants.

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ABSTRACT One of the major drawbacks of this final disposal technique is leachate production, which occurs due to the degradation of organic matter and rainwater percolation. The leachate composition is quite varied, with high organic load and various compounds that may be toxic to the environment. To reduce the polluting potential of the leachate, it must be subjected to an appropriate treatment. Biological treatments are widely used in the treatment of leachate, although these technologies have some drawbacks. As an alternative to conventional biological treatments, rotating biological reactors are used. The objective of this study was to determine the efficiency of a pilot scale rotating biological reactors in the removal of biochemical oxygen demand, chemical oxygen demand, and phosphorus from the landfill leachate. Effluent toxicity and rotating biological reactors's ability to remove this toxicity were also verified by calculating the germination index of lettuce (Lactuca sativa) and cucumber (Cucumis sativus) seeds. The reactor showed an average efficiency of 75.99% of biochemical oxygen demand removal, 33.53% of chemical oxygen demand removal, and 16.04% of phosphorus removal. In fact, the cucumber and lettuce seeds proved sensitive to the toxicity of the effluent. For crude leachate, the germination index values of lettuce and cucumber were 13.28 and 49.61%, respectively. In this study, rotating biological reactors obtained a good efficiency in the removal of toxicity from leachate. The germination index of the seeds for the treated effluent was 60.9% for lettuce and 82.49% for cucumber.

RESUMO Diante do crescimento populacional acelerado e do desenvolvimento econômico, grande quantidade de resíduos tem sido gerada nos grandes centros urbanos. Esses resíduos devem ser coletados e dispostos adequadamente, sendo os aterros sanitários os locais mais adequados para a sua disposição. Um dos grandes inconvenientes dessa técnica de disposição final é a produção de um líquido lixiviado, proveniente da degradação da matéria orgânica e da percolação da água da chuva. A composição do lixiviado é bastante variada, com elevada carga orgânica e diversos compostos que podem ser tóxicos ao meio ambiente. Para determinar a toxicidade do lixiviado são amplamente utilizados testes fitotoxicológicos, como o índice de germinação de sementes. Com o intuito de reduzir o potencial poluidor do lixiviado, este deve ser submetido a um tratamento adequado. Tratamentos biológicos são bastante utilizados, mas possuem algumas desvantagens. Como alternativa aos tratamentos biológicos convencionais, surgem os reatores biológicos rotatórios. O objetivo deste estudo foi determinar a eficiência de uns reatores biológicos rotatórios em escala piloto na remoção da demanda bioquímica de oxigênio, da demanda química de oxigênio e de fósforo do lixiviado do aterro. Também foi verificada a toxicidade do efluente e a capacidade dos reatores biológicos rotatórios para remover essa toxicidade por meio do cálculo do índice de germinação de sementes de alface (Lactuca sativa) e pepino (Cucumissativus). O reator utilizado neste trabalho obteve eficiência média de 75,99% de remoção de demanda bioquímica de oxigênio, 33,53% de remoção de demanda química de oxigênio e 16,04% de remoção de fósforo. As sementes de alface e pepino mostraram-se bastantes sensíveis à toxicidade do efluente. Para o lixiviado bruto, os índices de germinação da alface e do pepino foram, respectivamente, 13,28 e 49,61%. Neste estudo, os reatores biológicos rotatórios obtiveram boa eficiência na remoção da toxicidade do lixiviado. O índice de germinação das sementes para o efluente tratado foi de 60,9% para a alface e de 82,49% para o pepino.

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This work aimed to evaluate the composting of the mixture of residues from fish filleting, using sawdust as a structuring material as an alternative for stabilization, through physical-chemical analysis and phytotoxicity. The experiment was carried out in a composter 1.10 m long, 1.50 m wide, and 1.20 m high and presenting 2.50 m in total height, which received the mixture of fish filleting wastes and sawdust in a5:3 ratio, respectively. The results demonstrated that composting in cells is an efficient alternative for the decomposition of the mixture of fish filleting and sawdust residues. The rapid decomposition of fish waste and the low C/N ratio harms the development of thermophilic microorganisms during the composting of the mixture of fish filleting and sawdust residues. The compaction of the sawdust layers and the absence of stirring in the composting method in cells collaborate for the compost to need a time greater than 60 days to be recommended as simple organic fertilizer. The biomass stirring is necessary so that sawdust can be considered a good structuring agent. The phytotoxicity test should be taken into account by the Normative Instruction n° 25/2009 as an indicator of compost maturity.

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RESUMO Os resíduos de serviços de saúde (RSS) são todos aqueles resíduos gerados nos serviços que prestam atendimento à saúde humana ou animal. Os RSS são classificados em cinco grupos (Grupo A, Grupo B, Grupo C, Grupo D e Grupo E), dos quais uma parcela apresenta periculosidade. A legislação brasileira recomenda que os resíduos pertencentes ao Grupo D sejam reciclados. Contudo, com base na má segregação existente, o encaminhamento desses materiais representa riscos aos profissionais que manejam os resíduos intra e extraestabelecimentos de saúde, incluindo os trabalhadores que atuam junto às cooperativas de triagem de materiais recicláveis. Nesse contexto, este trabalho teve como objetivo verificar a presença de RSS destinados inadequadamente às cooperativas de triagem de materiais recicláveis de um município da zona Sul do Rio Grande do Sul. Para tanto, foi realizada uma caracterização quali-quantitativa dos RSS incidentes nas cinco cooperativas do município durante o período de quatro semanas. A partir dos resultados obtidos, verificou-se a presença de RSS no programa de coleta seletiva (PCS) municipal e, também, que a quantidade incidente varia conforme a cooperativa estudada e a semana avaliada. Ao final das caracterizações, foram quantificados 36,23 kg de RSS entre todas as cooperativas. Tais resultados indicam falhas na segregação e na destinação de RSS, seja pela população e/ou pelos estabelecimentos de saúde, além de evidenciarem a fragilidade existente no PCS do município. À vista disso, torna-se necessária a implementação de políticas públicas, tanto educativas quanto de fiscalização, que sejam capazes de assegurar maior segurança no âmbito de trabalho das cooperativas de triagem de materiais recicláveis.

ABSTRACT Healthcare waste (HCW) is all the waste generated by human or animal health care activities. HCW is classified into five groups, of which a portion presents hazardousness. Brazilian legislation recommends that waste belonging to Group D be recycled. However, based on the poor existing waste segregation, the forwarding of these materials presents risks to the professionals who handle them inside and out of health care facilities, including the workers within recyclable material waste picker cooperatives. In such a context, this study aimed to investigate the presence of HCW inappropriately sent to waste pickers cooperatives of a municipality in the south of Rio Grande do Sul. To this end, a qualitative and quantitative characterization of HCW incidence in the five cooperatives of the municipality was performed during the period of four weeks. From the results obtained, it was possible to verify the presence of HCW in the municipal selective waste collection program and that HCW quantities vary according to the waste pickers cooperative studied and the week being evaluated. At the end of the characterizations, 36.23 kg of HCW were quantified amongst all the cooperatives. Such results indicate flaws in HCW segregation and destination, either by the population and/or by health care facilities, in addition to showing the fragility in the municipality's selective waste collection program. In view of this, it is necessary to implement public policies, both educational and supervisory, that can ensure greater safety in the work environment of recyclable material waste picker cooperatives.

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The aim of this study was to evaluate the phytotoxicity of raw and treated effluents from a parboiling rice industry in the south of Brazil. The evaluation included 19 physicochemical parameters and a phytotoxicity test using lettuce and cucumber seeds as bioindicators. The germination index (GI) of both seeds was decreased when in contact with the raw effluent (p < 0.05) and with the treated effluent reduced the GI of cucumber seeds (p < 0.05) and the root length (RL) of lettuce seeds (p < 0.05). For lettuce seeds exposed to the treated effluent there was a negative correlation (p < 0.05) between RL and Mn (- 0.82) and between GI and Fe (- 0.68). For cucumber seeds in the raw effluent, the Fe showed negative correlation (p < 0.05) with seed germination (- 0.75), but, in the treated effluent, their GI presented positive correlation (0.61) with the ammoniacal-N (p < 0.05). The results indicated that both effluents showed phytotoxicity for lettuce and cucumber seeds.

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Abstract Flotation sludge (FS) is produced in huge amounts at slaughterhouses in western Santa Catarina, Brazil. This waste is rich in plant nutrients and a valuable resource for soil amendments. Five FS composts were tested as a replacement for chemical fertilizers (QF), namely T1 (75% poultry manure (PM) and 25% sawdust (SD)); T2 (50% PM and 50% SD); T3 (25% PM and 75% SD); T4 (100% PM and 0% SD); and T5 (0% PM x 100% SD). For lettuce plants, treatments containing composted FS resulted in an increased number of leaves, leaf area and leaf fresh weight (LFW). T1 presented the best results with increases of 1.4 fold in LFW compared to plants supplemented with QF. T2 was the most effective treatment for radish with the best results of root fresh weight and root diameter. Although T4 had the highest nitrogen content, it did not present the best results in growth performance for lettuce or radish. The presence of higher proportions of SD in composts (25% for lettuce and 50% for radish) improved the physical characteristics of the soil and proved to be a more balanced compost.

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Alguns pesquisadores e laboratórios clínicos utilizam apenas uma técnica para detecção de parasitos intestinais, podendo isto subestimar os achados. Enteroparasitos afetam principalmente populações com vulnerabilidade social, como os catadores. Alguns destes trabalhadores se reúnem em cooperativas, melhorando a condição de trabalho e o rendimento mensal, porém ainda não é o adequado, sendo por vezes insalubre. Nosso objetivo foi verificar a prevalência de enteroparasitos e comparar duas técnicas parasitológicas em suas medidas de efeito em catadores de material reciclável que trabalhavam em cooperativas no Sul do Brasil. Três amostras de fezes de 48 catadores, de seis cooperativas, foram coletadas em dias alternados, para a análise de parasitos. Duas técnicas de concentração de amostra foram utilizadas (Faust e Ritchie) e testadas para verificação da melhor a ser utilizada. A prevalência de parasitos em catadores foi de 62,5% (30/48) utilizando as duas técnicas em paralelo, sendo que quando utilizadas sozinhas, essa prevalência foi menor. Diagnosticaram-se helmintos e protozoários, tanto patogênicos quanto comensais. A partir da análise estatística, provou-se que as técnicas parasitológicas fornecem melhores resultados quando utilizadas em paralelo, ou seja, quando utilizamos as duas técnicas juntas e em três amostras de fezes.

Some researchers and clinical laboratories use just one technique for the detection of enteroparasites, allowing substandard findings. Enteroparasites mostly affect the socially vulnerable population, like the waste pickers. Some of these workers are gathered in cooperatives where work conditions and monthly wage are better. However, this environment is still not adequate being, sometimes, unsanitary. The objective was to study the enteroparasite prevalence and compare the two parasitological techniques in their effect measure in recyclable waste picker who were working in cooperatives in the south of Brazil. Three stool samples from 48 pickers from six cooperatives were collected in alternate days for parasite analysis. Two sample concentration techniques were used (Faust and Ritchie) and tested to verify which was the best to use. The parasite prevalence in waste picker was 62.5% (30/48), using the two techniques concurrently. When used individually, the prevalence was lower. Commensal and pathogenic helminths and protozoan were diagnosed. From the statistical analysis, it was proved that the parasitological techniques provide better results when used concomitantly, that is, when using the two techniques at the same time in three stool samples.

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This study evaluated the phytotoxic effects of raw and treated effluents from a swine slaughterhouse on cucumber and lettuce seeds and determined correlations among physicochemical characteristics of such effluents and the germination of seeds used as bioindicators. Physicochemical parameters were characterized for both effluents and their phytotoxicity was determined through the germination index (GI), the root length (RL) and the number of germinated seeds (SG) for both plant species. The effluents treatment system was efficient to reduce the concentration of some physicochemical parameters to levels within those recommended by the Brazilian legislation, except for P, ammoniacal N and TKN concentration. Although phytotoxicity of the treated effluent was less in comparison to the raw effluent, the GI for cucumber and lettuce seeds submitted to each of the tested effluents was lower than 80%. Thus, both effluents were phytotoxic for the tested bioindicators (p<0.05). For lettuce seeds, the GI presented negative correlations (p<0.05) with the total Kjeldahl N (-0.93) and the surfactants concentration (-0.83) in the raw effluent. The Zn concentration in the treated effluent showed a negative correlation (p<0.05) with the GI of both lettuce (-0.63) and cucumber seeds (-0.64). Therefore, effluents from swine slaughterhouses may impair the germination of the evaluated plant species if used for agricultural purposes.

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ABSTRACT The need for cleaner sources of energy has stirred research into utilising alternate fuel sources with favourable emission and sustainability such as biodiesel. However, there are technical constraints that hinder the widespread use of some of the low cost raw materials such as pork fatty wastes. Currently available technology permits the use of lipolytic microorganisms to sustainably produce energy from fat sources; and several microorganisms and their metabolites are being investigated as potential energy sources. Thus, the aim of this study was to characterise the process of Staphylococcus xylosus mediated fermentation of pork fatty waste. We also wanted to explore the possibility of fermentation effecting a modification in the lipid carbon chain to reduce its melting point and thereby act directly on one of the main technical barriers to obtaining biodiesel from this abundant source of lipids. Pork fatty waste was obtained from slaughterhouses in southern Brazil during evisceration of the carcasses and the kidney casing of slaughtered animals was used as feedstock. Fermentation was performed in BHI broth with different concentrations of fatty waste and for different time periods which enabled evaluation of the effect of fermentation time on the melting point of swine fat. The lowest melting point was observed around 46 °C, indicating that these chemical and biological reactions can occur under milder conditions, and that such pre-treatment may further facilitate production of biodiesel from fatty animal waste.

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