João Alberto Ferreira

A avaliação da carga fisiológica de trabalho na legislação brasileira deve ser revista! O caso da coleta de lixo domiciliar no Rio de Janeiro

The physiological workload (PW ) involved in garbage collection was assessed in a probabilistic sample of 70 Rio de Janeiro city garbage collectors to determine the adequacy of Brazilian labor legislation regarding classification of work. PW was measured as energy expenditure (EE) and heart rate (HR) during total work time (TT) and actual time (AT) in garbage collection on 4 consecutive days. Median EE values were 288.4 and 319.1 kcal.h-1 during TT and AT, respectively, indicating moderately intense work according to Brazilian legislation. However, PW was considered heavy when work classifications based on individual response to work were used: 1) ratio of EE and resting metabolic rate was above 5.0, indicating heavy workload according to the WHO; 2) mean percentage of maximal EE was higher (36.2 and 41.1% for TT and AT, respectively) than the limit for garbage collection (30%) suggested as maximal for Dutch workers; and 3) percentage of maximal HR reserve was also higher than 30% (32.2 and 37.5% for TT and AT, respectively). These results indicate the need for a revision of the workload classification in the Brazilian legislation to take individual workers’ characteristics into account.

Heart rate and energy expenditure during garbage collection in Rio de Janeiro, Brazil

Physiological workload is used to estimate the physical demand of tasks in the workforce, but limited information is available for the various work activities in developing countries. Eighty-three randomly selected male workers participated in the present study, aimed at assessing the physiological workload of garbage collection (GC) in Rio de Janeiro, Brazil. Heart rate (HR) was obtained on four consecutive workdays. Energy expenditure (EE) was extrapolated from heart rate data based on individual laboratory-established heart rate/oxygen consumption curve in 70 workers. Mean HR during GC was 104.0 +/- 11.7 bpm (+/- SD), representing 56.9 +/- 7.5% of maximum heart rate. EE was 1608.3 +/- 738.5 kcal for an average of 293.1 +/- 103.9 minutes of work per day. Based on all measurements, work in garbage collection in Rio de Janeiro can be considered excessively heavy. These data emphasize the need to develop appropriate classification of workload to be used in health-related research and in the development of maximum acceptable work time in association with the physiological workload, particularly in developing countries.

Avaliação de impactos do efluente do tratamento combinado de lixiviado de aterro de resíduos sólidos urbanos e esgoto doméstico sobre a biota aquática

The impact on tilapia fish of combined treatment of landfill leachate and domestic sewage was monitored in a waste treatment plant that operated on a pilot scale using the activated sludge process. Biomarkers of sub-lethal toxicity were used to indicate the possibility of damage to organisms due to interaction with pollutants. The concentration of metallothioneins did not indicate the increased presence of metals in fish exposed than in control groups. Acetylcholinesterase enzyme activity was inhibited in only one of the exposed groups, indicating the possible presence of organophosphate and/or carbamate pesticides in treated effluent. The PAHs used as biomarkers (naphthalene, pyrene, benzo(a)pyrene and 1-hydroxypyrene) indicated that exposed fish had a greater absorption of PAHs than control groups of fish, indicating the likely presence of these compounds in at least one of the combined treatment effluents. The frequencies of micronuclei and other erythrocytic nuclear abnormalities also indicate greater genotoxic damage in cells of organisms exposed than in control groups. The use of biomarkers proved to be important to permit an evaluation of sub-lethal damage present in organisms exposed to the pollution source studied.

Caracterização microbiológica de lixiviados gerados por resíduos sólidos domiciliares e de serviços de saúde da cidade do Rio de Janeiro

The present paper consisted on the microbiological characterization of leachate generated from solid waste from health services and municipal solid waste. This study aimed to support the discussion about the need for differentiated treatment and disposal for the health services solid waste. The following parameters were selected: total coliforms, thermotolerant coliforms, Escherichia coli, Enterococci, trials for Pseudomonas aeruginosa, and Salmonella and other Enterobacteria, analysis of susceptibility to antimicrobials and research on antimicrobial activity of the leachate. Expressive densities were observed in microbial populations in health services and municipal solid waste, with values ranging from 108 to 109. In both wastes, resistant and susceptible strains to antimicrobials occurred and none were resistant to all antibiotics tested. Results showed similarities for both types of waste and reinforce the recommendation for health services and municipal solid waste co-disposal in sanitary landfills.

Wetlands para tratamento de lixiviados de aterros sanitários: experiências no aterro sanitário de Piraí e no aterro metropolitano de Gramacho (RJ)

ABSTRACT The Group of Solid Waste of Environmental Engineering Program (PEAMB/UERJ) has been conducting research using constructed wetlands in landfi ll leachate treatment in the last fi ve years. These systems promote the absorption of nutrients by the vegetation and facilitate the degradation of organic material by microorganisms in the soil and the ones adhered to the roots. Experiments carried out in Pirai Municipality Landfi ll show removal of pollutants about 41% of COD and 51% of ammonium nitrogen. The results obtained in Gramacho’s landfi ll, present a reduction of 86% of COD load and 89% of ammonium nitrogen load. Wetlands seens to be a good alternative in the treatment of landfi ll leachate, especially in regions of tropical climate, where high temperatures improve effects of evapotranspiration. KEYWORDS: Constructed wetlands , leachate treatment, evapotranspiration, Gramachos’ metropolitan landfi ll, Pirai’s Landfi ll. C AMILLE F ERREIRA M ANNARINO Mestre em Engenharia Ambiental - PEAMB/UERJ. Engenheira Civil - Enfase em Engenharia Sanitaria e Ambiental – FEN/UERJ. Bolsista CNPq/ PROSAB

Chemical healthcare waste management in small Brazilian municipalities.

The disposal of healthcare waste (HCW) seems to have been solved in developed countries, while in most developing countries the problem persists because the disposal methods are expensive and larger than the budget of small- and medium-sized municipalities. The current study evaluates the encapsulation process for the disposal of medical chemical waste. The experiment was developed in the Piraí municipality (Rio de Janeiro State, Brazil) and the chemical wastes were produced in the local public hospital, as well as the 12 units of primary care health services. Chemical waste generated at health services units may include the liquid waste from cleaning materials and disinfectants, expired and unused pharmaceutical products, and cytotoxins. These are all considered hazardous waste products and they must be disposed of via an authorised system at approved sites (e.g. industrial landfills). The process of encapsulating chemical medical waste in concrete (cement, crushed stones and sand) followed by their disposal at sanitary landfills is a procedure that is not considered in Brazilian Legislation. Despite the oversight, this method of disposal was used in the municipality of Piraí, with the approval of the Rio de Janeiro State Agency for Environmental Control. The safety aspects of this method and the limits of its applicability, particularly in small municipalities, were evaluated in this study. The results indicate that, within certain parameters, this method may provide a viable solution for the disposal of HCW in small municipalities.

Mathematical modeling of COD removal via the combined treatment of domestic wastewater and landfill leachate based on the PACT process

The experiments performed in this study consisted of 16 batch reactors fed different mixtures of landfill leachate combined with synthetic wastewater treated using the Powdered Activated Carbon Treatment (PACT) process. The objective was to measure the COD mass removal per liter each day for each reactor using two models: the first model combined the variables PAC concentration (0 g·L−1, 2 g·L−1, 4 g·L−1, and 6 g·L−1) and leachate rate in the wastewater (0%, 2%, 5%, and 10%), and the second model combined the PAC concentration and the influent COD. The Response Surface Methodology with Central Composite Design was used to describe the response surface of both models considered in this study. Domestic wastewater was produced under controlled conditions in the laboratory where the experiments were performed. The results indicated that the PAC effect was null when the influent did not contain leachate; however, as the concentration of leachate applied to the mixture was increased, the addition of a higher PAC concentration resulted in a better COD mass removal in the reactors. The adjusted R2 values of the two models were greater than 0.95, and the predicted R2 values were greater than 0.93. The models may be useful for wastewater treatment companies to calculate PAC requirements in order to meet COD mass removal objectives in combined treatment.

Avaliação da implantação da Resolução n. 307/2002 do CONAMA sobre gerenciamento dos resíduos de construção civil

O gerenciamento da crescente massa de residuos solidos gerados e um dos principais problemas do mundo atual, considerando os riscos de esgotamento dos recursos naturais e os impactos ao meio ambiente e a saude publica. Neste c ontexto, este trabalho apresenta o panorama das construtoras em relacao ao gerenciamento de seus residuos solidos, com o objetivo de analisar o efeito da resolucao no 307/2002 - CONAMA, enfocando com maior detalhamento a reciclagem de RCD nos canteiros de obra, como forma de insercao dos residuos passiveis de reciclagem no processo produtivo. Verifica-se que a questao ambiental, por si so, nao funciona como motivadora para a implantacao do gerenciamento de RCD pelas construtoras e, para a incorporacao de no vas tecnologias, como a reciclagem de RCD no proprio canteiro de obra; e que a resolucao no 307/2002 do CONAMA ainda nao produziu os efeitos desejados. The management of the increasing volume of generated solid wastes is one of the main problems of the current world, considering the risks of exhaustion of the natural resources and the impacts to the environment and the public health. In this context, this work presents an overall view of the constructors related to the management of their solid wastes, a s established the objective to analyze the effect of the resolution no 307/2002 - CONAMA. Focusing, the recycling of CD and that the resolution no 307/2002 of the CONAMA still did not produce the expected results.

Water resources contamination: A study of São Pedro da Aldeia’s open dump

O trabalho apresenta os resultados de monitoramento das aguas subterrâneas e lagoas superficiais adjacentes ao lixao de Sao Pedro da Aldeia (RJ). Seis piezometros, tres lagoas e um poco cacimba a jusante foram utilizados para coleta de amostras. Sao apresentados os parâmetros fisicoquimicos determinados no campo: pH, condutividade eletrica (CE), potencial redox (Eh), e os resultados de ions analisados em laboratorio: Cl-, Na+, K+, e NH4+. Os resultados mostraram que a influencia do lixao sobre as aguas superficiais e subterrâneas, apos 17 anos em atividade, atinge entre 150 e 200 metros de distância, nao se observando uma atenuacao. Palavras-chave: lixao, contaminacao, recursos hidricos, Sao Pedro da Aldeia (RJ).