Presença da toxina microcistina em água, impactos na saúde pública e medidas de controle / Microcystin toxin in the presence of water, public health impact and control measures

As cianobactérias constituem um grupo de micro-organismos procariontes encontrado em ambientes aquáticos, os quais vêm sendo pesquisado devido à capacidade de produzir toxinas que causam grandes impactos à saúde pública e ambiental. A ocorrência de florações desses micro-organismos em reservatórios de água utilizada para abastecimento público tem sido frequente e prejudicado os usos múltiplos da água. Algumas cepas produzem florações nocivas liberando compostos neurotóxicos, hepatotóxicos ou irritantes à pele de seres humanos e animais, podendo ocasionar intoxicação e morte. A literatura reporta a ocorrência de um acidente em Caruaru, Pernambuco, onde faleceram 65 pacientes que faziam hemodiálise, devido à presença de microcistina-LR na água que consumiram. Esse estudo objetivou realizar uma revisão sobre a presença da toxina microcistina em água, os impactos e medidas de controle. Foram relatados os principais métodos utilizados para a remoção e quantificação da microcistina em água, bem como sua relação com a saúde humana.

Cyanobacteria are a group of prokaryotic microorganisms found in aquatic environments, which have been researched because of the ability to produce toxins that cause major public health impacts and environmental. The occurrence of seaweed buddings in reservoirs used for public supplying has been frequent, and has affected the multiple uses of the drinking water. Some strains of seaweed, in special the cyanobacterial, can produce toxins as the microcystins, which are responsible for the intoxication and death of animals and humans.The literature reports the occurrence of an accident in Caruaru, Pernambuco, where he died 65 hemodialysis patients who were due to the presence of microcystin-LR in water. This study aimed to perform a review of the presence of the toxin microcystin in water, impacts and control measures. Reported were the main methods used for the removal and quantification of microcystins in water and its relation to human health.

Silver discharged in effluents from image-processing services: a risk to human and environmental health.

In Brazil, only 20.2% of the municipalities have sewage collection and treatment. The use of medical diagnostic by radiographic processing generates effluents which may contain contaminants such as silver (Ag) that causes irreversible damage to health. They can also contaminate soil, water, and food if there is no treatment before disposal. This study aimed to identify and quantify the Ag concentration in radiographic film-washing water and fixer generated from radiographic processing in 12 Brazilian health institutions, in order to offer subsidies to the environmental and public health managers about this issue. The Ag values found in the washing water films samples ranged from 0.1 to 1,785.97 mg L(-1). In the fixer samples, the values ranged from 435.59 to 16,325.92 mg L(-1). These data are far above the values required by Brazilian legislation whose limit is 0.1 mg L(-1) for Ag in effluents released directly or indirectly into the environment. This research reveals that the disposal of Ag in this kind of effluent needs to be monitored and controlled by the Brazilian government in order to protect both the human and environment health from those contaminants.

A molecular modeling and QSAR study of suppressors of the growth of Trypanosoma cruzi epimastigotes.

In this work, we have used molecular modeling and QSAR tools to study 18 dithiocarbamate suppressors of the growth of Trypanosoma cruzi epimastigotes, which have been reported in the literature as superoxide dismutase (SOD) inhibitors. The principal component analysis (PCA) showed that the descriptors superficial area, heat of formation, logarithm of the partition coefficient, charge of the nitrogen atom from the dithiocarbamate group and Charges of the two carbon atoms adjacent to that nitrogen are responsible for the classification between the higher and lower trypanomicid activity. Using multiple linear regression (MLR) and docking methods it was possible to identify the probable bioactive isomers that suppress of the growth of T. cruzi epimastigotes. Our best partial least square (PLS) model obtained with these six descriptors yields a good correlation between experimental and predicted biological activities and compares two different SODs as possible target for interaction with the dithiocarbamates.

Pesticidas e seus respectivos riscos associados à contaminação da água / Pesticides and respective risks associated to water contamination

Efetuou-se revisão de literatura sobre os principais tipos de pesticidas, bem como suas toxicidades e riscos associados contaminação da água e do meio ambiente. Os pesticidas podem ser bastante úteis na produção agrícola, especialmente quando o clima favorece o desenvolvimento de pragas. Contudo, o seus uso deve ser corretamente orientado por profissionais e a saúde da população. Para esses fins, as pesquisas na área de pesticidas vêm caminhando na direção da obtenção de compostos cada vez menos tóxicos para os seres vivos