Coliform density in oyster culture waters and its relationship with environmental factors

The objective of this work was to evaluate the total and thermotolerant coliform densities in the oyster culture water of Cananeia, SP, Brazil, correlating these densities with environmental variables and tidal variations. Superficial water samples were collected in two tide conditions (spring and neap) from three areas of Cananéia municipality (Mandira, Itapitangui and Cooperostra). The three studied areas showed good conditions for the culture regarding coliform densities. The two tidal conditions differed significantly as to total coliform concentration; however, the same procedure was not performed for thermotolerant coliforms. No correlation was observed between water temperature, pH, and concentrations of total and thermotolerant coliforms. Coliform density was positively correlated with rainfall and negatively correlated with salinity. Spring and neap tides differed significantly as to coliform number. Simple diagnosis of environmental conditions of the crop fields is insufficient to assess water quality of shellfish cultivation. A continuous monitoring program of planted areas is necessary both for the assessment of water quality potential for marine culture and for ensuring safe consumption of seafood, besides constituting an important tool to understand the relationships between contamination and the involved environmental variables.

Haematite in Lateritic Soils Aids Groundwater Disinfection

Microbiologically contaminated water severely impacts public health in low-income countries, where treated water supplies are often inaccessible to much of the population. Groundwater represents a water source that commonly has better microbiological quality than surface water. A 2-month intensive flow and quality monitoring programme of a spring in a densely settled, unsewered parish of Kampala, Uganda, revealed the persistent presence of high chloride and nitrate concentrations that reflect intense loading of sewage in the spring’s catchment. Conversely, thermotolerant coliform bacteria counts in spring water samples remained very low outside of periods of intense rainfall. Laboratory investigations of mechanisms responsible for this behavior, achieved by injecting a pulse of H40/1 bacteriophage tracer into a column packed with locally derived granular laterite, resulted in near-total tracer adsorption. X-ray diffraction (XRD) analysis showed the laterite to consist predominantly of quartz and kaolinite, with minor amounts (<5%) of haematite. Batch studies comparing laterite adsorption capacity with a soil having comparable mineralogy, but with amorphous iron oxide rather than haematite, showed the laterite to have a significantly greater capacity to adsorb bacteriophage. Batch study results using pure haematite confirmed that its occurrence in laterite contributes substantially to micro-organism attenuation observed and serves to protect underlying groundwater.

Faecal bacteria in Perna perna (Linnaeus, 1758) (Mollusca: Bivalvia) for biomonitoring coastal waters and seafood quality

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Decaimento bacteriano em lagoas de estabilização no Nordeste brasileiro

Stabilization pond system consisting in more sewage treatment used in Rio Grande do Norte (RN), Brazil, representing about 90% of all systems. Fecal bacteria are removed mainly facultative ponds and in maturation ponds. Many factors influence bacterial decay, such as the levels of pH and DO, temperature, light intensity, HDT and nutrient availability. The bacterial decay rate (Kb) is calculated considering many variables, but the hydraulic regime is a significant influence for microorganisms removal, and the dispersed flow which best characterizes a stabilization pond. However, some authors developed equations for the Kb accordant plug flow and complete mixing. This research study aimed to evaluate the bacterial decay of fecal coliform and Enterococcus sp. in stabilization ponds designed to treat domestic sewage, full-scale, in RN. All systems have assessed pretreatment, a facultative pond (LF) followed by two maturation (LM1 and LM2). The parameters availed were: temperature, pH, DO, BOD5, COD, fecal coliform, Enterococcus sp., Chlorophyll a, total suspended solids, fixed and volatile. In general, there were not significant differences for pH, DO and temperature in the ponds, except for the new systems, since they have low flow and hydraulic loads. The removal of organic matter in the ponds was low, about 70%, and nearly all are overloaded organic and operational problems. The bacterial removals were low, with average 96% for LF for fecal coliform, and 98% for Enterococcus sp.; LM1 were in itself a removal for fecal coliform about 71%, and 81% for Enterococcus sp.; LM2 have efficiency of 69% for fecal coliform, and 68% for Enterococcus sp. The equation proposed by Von Sperling (1999), according to the dispersed flow regime, generated empirical values of Kb more approximate to calculated values of Kb. On average, the calculated Kb to coliforms in the LF was 0.31 d-1, and for both maturation ponds were 0.35 d-1. For Enterococcus sp. the average was 0.40 d-1 for LF, 0.55 d-1 for LM1, and 0.58 d-1 for LM2. These results also showed that the Kb obtained in full-scale systems are smaller than those found in pilot-scale ponds. Moreover, one can say that the equation proposed by Marais (1974), according to the complete-mix regime, overestimates Kb. Actual results of Kb indicated that fecal coliforms are more resistant to adverse conditions present in stabilization ponds than Enterococcus sp., therefore, an indicator of microbiological safety and efficiency. The factors significant interventions in the rate of bacterial decay were concentrations of COD, the organic loading and HDT. The few Kb relationship between pH, DO and temperature were not significant. Finally, we conclude that it s essential to correct operation and maintenance, for not performing these activities is one of the main factors contributing to low rates of bacterial decay.

Avaliação da eficiência da remoção de matéria orgânica e microbiológica de três sistemas de lagoas de estabilização em série na Grande Natal-RN: Beira Rio, Jardim Lola I e Jardim Lola II

Waste stabilization ponds are the main technology in use for domestic sewage treatment in Rio Grande do Norte State (RN), northeast Brazil. The are around 80 systems, constructed mainly by municipal city halls, being series comprised by a primary facultative pond followed by two maturation ponds the most used configuration. Due to problems related with the production and destination of sludge and generation of bad odors, the designers have avoided the use of anaerobic lagoons. The majority of systems are rarely monitored to verify their efficiencies and to get new project parameters for future designing. This work has as purpose to make a diagnosis of efficiency of three series of waste stabilization pond series (WSPS) of Jardim Lola 1, Jardim Lola 2 and Beira Rio, located in the North Zone of the city of the Natal/RN, treating domestic raw sewage, on the removal of organic matter and thermotolerant coliform, comparing the operational conditions of the systems this inside of the bands foreseen in the project, through parameters BOD5, QOD, thermotolerant coliforms, dissolved oxygen, pH, temperature, ammoniac nitrogen, total and suspended solids. The work was carried through in the WSPS, all constituted by a primary facultative pond followed by two maturation ponds. Socioeconomic characteristics of population are predominantly low and all the plants are very near of the contributing basins. The series were monitored from of May the November of 2002, totalizing 20 collections of grab samples of raw sewage and ponds effluents between 8:00 and 9:50 h. The main aspect to be detached by the results was the great concentration of organic matter (BOD and COD) and microorganisms the raw sewage which were around two times more concentrated than those values foreseen one in project. Considering all series the highest removals of organic matter were observed in system Beira Rio (84 and 78% of BOD and COD, respectively), which presented high hydraulic detention time (TDH = 89 days). On the other hand, Jardim Lola 1 and Jardim Lola 2 presented a much lower values of HDT (36 days and 18 days respectively) and their removals of BOD and COD were the same (76% and 60%, respectively). The Beira Rio WSPS, was the most efficient verified in relation to solids and ammonia, proving the great influence of the operational variables such as HDT and applied surface organic loadings on the performance of pond series. Although the treatment plants have reached efficiencies of thermotolerant coliforms around 99,999%, the concentrations in the final effluent can be considered very high for launching in aquatic bodies, particularly those produced by Jardim Lola 1 and Jardim Lola 2 series

Caracterização de efluentes de viveiros de engorda de rã-touro (lithobates catesbeianus, Shaw, 1802)

Aim: Current analysis characterizes the effluent from bullfrog-rearing ponds during the grow-out phase; Methods: Temperature, pH, dissolved oxygen, electric conductivity, turbidity, total phosphorus, N-NH3, N-NO3, BOD5 and COD and the number of thermotolerant coliforms (Escherichia coli) of the inlet and outlet water of the ponds were analyzed twice a week. Assay consisted of a completely randomized experimental design with two treatments (inlet and outlet water) and six repetitions in a split-plot, coupled to collection over time as subplot; Results: All variables were significantly different (p < 0.05) between treatments and over time (p < 0.05). Average rates of temperature, pH and dissolved oxygen levels of the supply water were higher when compared to those of the effluent. The other variables such as conductivity, turbidity, total phosphorus, ammonia, nitrate, biological oxygen demand, chemical oxygen demand and E. coli were higher in the effluent when compared to rates in the supply water; Conclusions: The management during grow-out phase caused the deterioration of the water quality, with increasing levels of dissolved nutrients and the number of thermotolerant coliform. Ammonia and phosphorus levels in the effluent, caused by waste food, skin and feces, accelerate the eutrophication process of the receiving water body. Further studies on effluent treatment are required.

Características microbiológicas de sushis adquiridos em estabelecimentos que comercializam comida japonesa

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação da qualidade microbiológica de peito, coxa e coração de frango comercializados em diferentes estabelecimentos da cidade de Jaboticabal, SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Condições oceanográficas, ocupação territorial e problemas ambientais na praia do Atalaia (nordeste do Pará, Brasil)

A conservação e gestão da zona costeira da região amazônica merecem atenção especial, devido à riqueza de seus recursos naturais. O presente estudo visa avaliar os impactos dos eventos naturais e atividades humanas na praia de Atalaia, situada no estado do Pará (Brasil), e o desenvolvimento de diretrizes para a implementação de programas de gestão costeira. Os dados foram coletados entre novembro/2008 e novembro/2010. Quatro conjuntos de variáveis foram avaliados: (i) variáveis físicas (climatologia, hidrodinâmica e morfodinâmica), (ii) variáveis hidrológicas (temperatura da água, salinidade, pH, turbidez, oxigênio dissolvido e nutrientes inorgânicos dissolvidos, clorofila a e níveis de coliformes termotolerantes), (iii) desenvolvimento urbano e (iv) distribuição espacial de serviços e infraestrutura. Os resultados indicam que o clima e as condições hidrodinâmicas foram os principais fatores responsáveis pelas flutuações na qualidade de água, turbidez, oxigênio dissolvido, nutrientes inorgânicos dissolvidos e concentrações de clorofila a. A descarga de esgoto doméstico não tratado foi responsável pela contaminação bacteriológica, embora a rápida turbulência decorrente da alta energia hidrodinâmica do ambiente tenha limitado a contaminação por coliformes termotolerantes. Esta alta energia hidrodinâmica, principalmente durante as marés equinociais de sizígia e a falta de planejamento urbano gera outros problemas, tais como a erosão costeira. A área de estudo é caracterizada por altas taxas pluviométricas (> 1900 mm durante a estação chuvosa), ventos de NE com velocidades médias mensais superiores a 4,36 m/s na estação seca e 3,06 m/s na estação chuvosa, condições de macromaré (alcance da maré > 4,0 m), velocidades moderadas de correntes de maré (superior a 0,5 m/s) e alturas de ondas significantes superior a 1,5 m. Em março e junho (meses chuvosos), a corrente de maré vazante alcançou um máximo de 0,4 m/s. O ciclo de maré foi fracamente assimétrico com a maré vazante durando mais de 6 horas e 40 minutos. A energia das ondas foram fracamente moduladas pela maré baixa devido à atenuação das ondas em bancos de areia. A temperatura da água foi relativamente homogênea (27,4°C a 29,3°C). A salinidade variou de 5,7 (junho) a 37,4 (novembro). A água foi bem oxigenada (superior a 9,17 mg/L), turva (superior a 118 NTU), alcalina (acima de 8,68) e eutrófica (máximo de 2,36 μmol/L para nitrito, 24,34 μmol/L para nitrato, 0,6 μmol/L para fosfato e 329,7 μmol/L para silicato), além de apresentar altas concentrações de clorofila a (acima de 82 mg/m³). As condições naturais observadas no presente estudo indicam a necessidade de uma revisão dos critérios hidrológicos usados para avaliação de praias por agências nacionais e internacionais e sua adaptação para a realidade da costa amazônica. A falta de sistema de saneamento público levou a contaminação bacteriológica e a perda da qualidade da água. Com relação ao estado morfodinâmico, as condições dissipativas foram encontradas durante alta a moderada energia hidrodinâmica (condições equinociais e não-equinociais), porém em novembro as maiores alturas de ondas geraram características de barred dissipative, enquanto nos outros meses características nonbarred foram dominantes. Desta forma, o modelo proposto por Masselink & Short (1993) parece não ser ideal para ser aplicado em praias com características similares a praia de Atalaia, na qual a energia das ondas é modulada pela presença de bancos de areia durante algumas fases da maré.

Avaliação microbiológica de carcaças congeladas de perus adquiridas no comércio varejista

Pós-graduação em Medicina Veterinária - FCAV

Microbiological quality of whole and filleted shelf-tilapia

Despite fish being a rich source of animal nutrients and having numerous associated health benefits, it is an extremely perishable food, prone to a wide range of hazards. The bacterial load associated with shelf-whole-fish organs (e.g. digestive tracts and skin) or mishandling of fish may be a vehicle of infection and become a risk to public health. The objective of this paper is to evaluate the microbiological quality of whole ungutted and filleted shelf-tilapia, as well as assess the safety for human consumption. For this purpose, in order to investigate the distribution and occurrence of bacterial populations, the count of total and thermotolerant coliforms, coagulase-positive Staphylococcus and presence of Salmonella spp. was determined. This paper shows that all fish organs were contaminated with thermotolerant coliform. Skin and fillet show higher populations and occurrence of all microorganisms analyzed. Lower bacterial populations were recovered from the gut and muscles of whole tilapia. Two samples of fillet were contaminated with coagulase-positive Staphylococcus. It can be concluded that the skin and filleted tilapia are important carriers of food-borne pathogens. In addition, fish might become an important cross and self-contamination source. (C) 2014 Elsevier B.V. All rights reserved.

Identificação de patógenos e qualidade higiênico-sanitária do caldo de cana (garapa), consumido no interior do estado de São Paulo

The state of São Paulo is the largest producer of cane sugar in Brazil, with approximately 346 million tons in 2008/2009. This great production, associated with hot weather favors trade in sugar cane juice in most cities in the state. Contamination by parasites usually occurs during production but the contamination by bacteria is related with foodhandlers, equipment (grinders) and utensils used in the extraction. Due the lack of data in Botucatu and region, the objective of this study was to analyze 50 samples of syrup, according to the microbiological requirements of RDC Nº 12 (determination of Most Probable Number of thermotolerant coliform and the presence of Salmonella sp) as well the presence of Staphylococcus aureus and Trypanosoma cruzi. Salmonella sp., Staphylococcus aureus and Trypanosoma cruzi were not found, however 82% of the samples presented a higher contamination by thermotolerant coliform than that allowed by microbiological parameters, demonstrating inadequate conditions for retail, besides the lack of hygienic instructions of the sellers

Qualidade higiênico-sanitária de sorvetes e sobremesas, na cidade de Botucatu, SP, Brasil, e verificação da produção de enterotoxinas por Staphylococcus aureus

Food poisoning can cause infection on its consumers by the presence of pathogenic bacteria, such as Salmonella and Staphylococcus aureus. Therefore, it is important to check its quality, which can be affected by many factors. The sanitary quality of foods can be assessed by thermotolerant coliform. Since food safety is a matter of great concern, this study aimed to evaluate the hygienic sanitary conditions of samples of ice cream and desserts marketed in the city of Botucatu, by determining the most probable number (MPN) of thermotolerant coliform, identification and enumeration of coagulase positive staphylococci and verification of classical enterotoxin production by strains of S. aureus and also for detecting the presence of Salmonella sp. Among the ice cream analyzed, 56.3% were unfit for consumption and between the creamy desserts, the percentage of unfit samples was 33.3%. Coagulase positive Staphylococcus and Salmonella were not found in the samples. It is then an inadequacy in handling and / or storage conditions in a considerable number of samples, indicating need for improvement in the conditions of preparation

Efeito da infestação de macrófitas aquáticas na comunidade planctônica em um viveiro de piscicultura

Pós-graduação em Microbiologia Agropecuária - FCAV

Parâmetros bióticos e abióticos em tanques de piscicultura tratados com macrófita aquática e perifíton

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)