The response of nitrous oxide emissions to different operating conditions in activated sludge wastewater treatment plants in Southeastern Brazil.

The continuous measurements of N2O emissions from the aeration tanks of three activated sludge wastewater treatment plants (WWTPs) operated with biological nitrogen removal (BNR) and non-BNR were performed during the different operating conditions of several parameters, such as aeration, dissolved oxygen (DO) profiling and organic shock loading (with landfill leachate). The nitrification process is the main driving force behind N2O emission peaks. There are indications that the variation of the air flow rate influenced N2O emissions; high N2O emissions denote over-aeration conditions or incomplete nitrification, with accumulation of NO2- concentrations. Thus, continuous measurements of N2O emissions can provide information on aeration adequacy and the efficiency of complete nitrification, with major focus on DO control, in order to reduce N2O emissions. An additional concern is the observed propensity of WWTPs in developing countries to receive landfill leachates in their wastewater systems. This practice could have adverse effects on climate change, since wastewater treatment during periods of organic shock loading emitted significantly higher amounts of N2O than without organic shock loading. In short, non-BNR WWTPs are subject to high N2O emissions, in contrast to BNR WWTP with controlled nitrification and denitrification processes.

Factors controlling nitrous oxide emissions from a full-scale activated sludge system in the tropics.

Despite interest in characterizing nitrous oxide (N2O) emissions from wastewater treatment plants (WWTPs) in several parts of the globe, there are few studies in tropical zones. This study focus on the contribution of the scientific knowledge of anthropogenic nitrogen greenhouse gas emissions to climate change in tropical countries, investigating factors controlling N2O emissions in a non-biological nitrogen removal municipal WWTP. In terms of operational parameters, dissolved oxygen (DO) concentrations displayed a biphasic impact on N2O production and emission, with the highest emission at DO of 2.0 mg O2 L(-1). The low solids retention time of 3 days also played a significant role, leading to nitrite accumulation, which is an important trigger for N2O production during nitrification. Furthermore, other factor especially important for tropical countries, namely, temperature, also had a positive correlation with N2O production. Emission factors estimated for this study were 0.12 (0.02-0.31)% of the influent total nitrogen load and 8.1 (3-17) g N2O person(-1) year(-1), 2.5 times higher than currently proposed emission factors. Therefore, the highly variability and dependence on operational parameters reinforce the use of a single emission factor is inadequate, especially for developing countries with limited or variable extent of biological wastewater treatment and in regions of the world with widely varying climate patterns.

Avanços e desafios em normatização de amostras grátis de medicamentos no Brasil / Advances and challenges in standardization of free samples of drugs in Brazil

Este trabalho analisou criticamente a legislação sobre amostras grátis de medicamentos no Brasil, pontuando alguns aspectos importantes relacionados à saúde da população. Foi realizado um levantamento das leis, decretos, normas e regulamentações que norteiam o assunto. A amostra grátis é uma das estratégias de publicidade e marketing usadas pela indústria farmacêutica. Em alguns casos, a indicação de certos medicamentos é baseada em dados técnicos apresentados pelos propagandistas. Por outro lado, os médicos que buscam informações técnicas em fontes com menor influência da indústria farmacêutica indicam menos os medicamentos novos, que na maioria das vezes são mais caros. Embora tenha sido observado um avanço na normatização em relação às amostras grátis, ela ainda é incipiente. Tópicos como o prazo mínimo para sua distribuição, quantidade máxima a ser entregue a cada prescritor, seu transporte, armazenamento e cuidados com o prazo de validade deveriam ser incluídas na legislação pertinente, como ocorre em outros países. Estas discussões deveriam ser retomadas com a menor influência possível dos laboratórios farmacêuticos, seguindo critérios técnico-científicos. Portanto, é necessário que este assunto seja contextualizado nas resoluções sobre amostras grátis de medicamentos, seguindo as normas das boas práticas de fabricação...

This paper critically analyzed the legislation on free samples of medicines in Brazil, scoring some important health-related aspects of the population. A survey of laws, decrees, rules and regulations that guide the subject was conducted. The free sample is one of the advertising and marketing strategies used by the pharmaceutical industry. In some cases, the designation of certain drugs is based on technical data provided by the propagandists. On the other hand, physicians seeking technical information on sources with less influence of the pharmaceutical industry indicate fewer new drugs, which most often are more expensive. Although an improvement in standardization has been seen for free samples, it is still incipient. Topics such as the time limit for its distribution, maximum to be delivered to each prescriber, transport, storage and care of the expiration date amount should be included in the relevant legislation, as in other countries. These discussions should be resumed with the least possible influence of pharmaceutical companies, following technical and scientific criteria. Therefore, it is necessary that this matter be contextualized in resolutions on free samples of medicines, following the standards of good manufacturing practices...

Fate of organochlorine 14C-dicofol in a lab-scale wastewater treatment / Destino do organoclorado 14C-dicofol no tratamento de efluentes

The fate of organochlorine 14C-dicofol in activated sludge process was investigated. Results showed that the major part of radioactivity remained adsorbed on biological sludge. Consequently, its final disposal deserves special attention. The small amounts of dicofol, biotransformed or not, which remained in the treated effluent could contaminate receiving bodies.

A dinâmica do organoclorado 14C-dicofol no processo de lodos ativados foi investigada. Os resultados mostraram que a maior parte da radioatividade ficou adsorvida no lodo biológico. Consequentemente, o seu descarte final merece atenção especial. Pequenas quantidades de dicofol, biotransformadas ou não, permanecem no efluente tratado podendo contaminar os corpos receptores.

Fate of organochlorine (14)C-dicofol in a lab-scale wastewater treatment.

The fate of organochlorine (14)C-dicofol in activated sludge process was investigated. Results showed that the major part of radioactivity remained adsorbed on biological sludge. Consequently, its final disposal deserves special attention. The small amounts of dicofol, biotransformed or not, which remained in the treated effluent could contaminate receiving bodies.