Ecotoxicological assessment of land ll leachate has become a priority to determine its impacts on the ecosystem. Toxicity assays with microorganisms stand out due to their quick response, low cost and ease of testing. In this context, the present study evaluated the acute toxic effects of leachates from two land lls of different ages and modes of operation to bacterium A. scheri and activated sludge microorganisms and the ammonia nitrogen and humic substances (HS) sensitivity to these organisms. Reductions greater than 30% in leachate toxicity were observed after ammonia removal for A. scheri and activated sludge microorganisms. After 97% removal of HS, the greater reductions in toxicity (44.28 to 79.82%) were veri ed for microbial species studied, indicating that the organic compounds (measured as chemical oxygen demand, total organic carbon and humic substances) were the primary pollutants responsible for the toxicity of the leachates. Concerning the organisms studied, A. scheri showed greater sensitivity to the leachates' pollutants compared to the activated sludge microorganisms. Nevertheless, a strong correlation was observed between A. scheri and activated sludge microorganisms' toxicity responses, suggesting that respirometry assay can be used to determine leachate toxicity.

Ecotoxicological assessment of landfill leachate has become a priority to determine its impacts on the ecosystem. Toxicity assays with microorganisms stand out due to their quick response, low cost and ease of testing. In this context, the present study evaluated the acute toxic effects of leachates from two landfills of different ages and modes of operation to bacterium A. fischeri and activated sludge microorganisms and the ammonia nitrogen and humic substances (HS) sensitivity to these organisms. Reductions greater than 30% in leachate toxicity were observed after ammonia removal for A. fischeri and activated sludge microorganisms. After 97% removal of HS, the greater reductions in toxicity (44.28 to 79.82%) were verified for microbial species studied, indicating that the organic compounds (measured as chemical oxygen demand, total organic carbon and humic substances) were the primary pollutants responsible for the toxicity of the leachates. Concerning the organisms studied, A. fischeri showed greater sensitivity to the leachates' pollutants compared to the activated sludge microorganisms. Nevertheless, a strong correlation was observed between A. fischeri and activated sludge microorganisms' toxicity responses, suggesting that respirometry assay can be used to determine leachate toxicity.

Este artigo objetivou-se em realizar um levantamento bibliográfico sobre a epidemiologia e fisiopatologia da psoríase, além de dá uma breve atualização sobre os seus tratamentos. Para metodologia deste trabalho, foi realizado um levantamento bibliográfico utilizando bancos de dados, como: Google Acadêmico, plataforma SciELO (Scientific Eletronic Library Online), PubMed (National Library of Medicine) e Bibliotecas digitais que estão disponíveis para pesquisa, assim como livros, dissertações, teses e monografias. A psoríase afeta 6% da população mundial, acometendo igualmente homens e mulheres. Caracteriza-se por inflamação imunomediada do tecido cutâneo, que resulta em placas eritematosa-escamosa descamativas de tamanhos diferentes, com fronteira bem definida ou irregular, que surgem em diversos locais do exterior da pele, tendo uma preferência pelos cotovelos, unhas, tronco, joelhos e couro cabeludo. Sua etiologia envolve aspectos genéticos e ambientais. O diagnóstico é clínico, sendo necessária a biópsia da lesão para confirmação apenas em alguns casos. Pode ser dividida em leve, moderada e grave, com grande variabilidade clínica, incluindo: vulgar, vale, palmoplantar, inversa, eritrodérmica, pustulosa, ungueal e articular. Atualmente não há cura, e o tratamento visa aliviar os sintomas e reduzir o número de irritações, podendo utilizar medicações tópicas ou sistêmicas dependendo da gravidade do quadro.

The landfill leachate treatment system inevitably will consist of processes that generate sludge. This sludge must be disposed in a way that minimizes its environmental impacts. The objective of this work is to evaluate the impact of co-disposal of sludge generated in leachate treatment plant with household solid waste (HSW). The sludges from leachate treatment evaluated in the present work were generated in a forced evaporation treatment system and in a lime treatment step. Nine cells simulating landfill were set up to evaluate the impact of sludge co-disposal with HSW. During 225 d of monitoring, the results showed that the cells were in the acid phase of waste degradation and, for all parameters except chemical oxygen demand (COD) and total organic carbon (TOC), the cells showed similar behavior to the control cells. Leachate from co-disposal cells E (evaporator sludge) presented greater COD and TOC than leachate from control cells (cell C), which in turn presented greater values than leachates from co-disposal cells L (lime sludge). The higher content of organic matter may have influenced waste degradation inside the cell with evaporator sludge. On the other hand, the lime in sludge may have reacted with organic matter inside the cells.

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