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Microbial Indicators (microbial + indicator)
Selected AbstractsEfficiency of permeable pavement systems for the removal of urban runoff pollutants under varying environmental conditionsENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 3 2010Kiran Tota-Maharaj Abstract Urban surface water runoff typically contains a high but variable number of pathogens, nutrients, and sediments that require removal before reuse. Permeable pavements can improve the water quality through interception, filtration, sedimentation, nutrient transformation, and microbial removal. There is currently insufficient scientific information available on the treatment efficiencies of permeable pavements combined with earth energy systems with regards to the removal of storm water pollutants such as nutrients, sediments, and microbial pollutants. This study evaluates the efficiency of 12 tanked combined systems during a medium-term study. The research assessed weekly the removal of the microbial indicators total coliforms, Escherichia coli, and fecal Streptococci, as well as the key nutrients ammonia-nitrogen, nitrate-nitrogen, and ortho-phosphate-phosphorus, and physical variables such as suspended solids and turbidity. Total coliforms, E. coli, and fecal Streptococci were removed by 98,99%. The ammonia-nitrogen and ortho-phosphate-phosphorus removal efficiencies were 84.6% and 77.5%, respectively. An analysis of variance indicated that the presence or absence of a geotextile did result in a very highly statistically significant difference (P < 0.001) with respect to the removal of both ammonia-nitrogen and ortho-phosphate-phosphorus. Suspended solids, turbidity, and biochemical oxygen demand were reduced by 91%, 82%, and 88%, respectively. These results indicate the potential of the proposed novel system in urban runoff pollutant removal and subsequent reuse of the treated water. © 2010 American Institute of Chemical Engineers Environ Prog, 2010 [source] Occurrence of coagulase-positive Staphylococci, microbial indicators and physical,chemical characteristics of traditional semihard cheese produced in BrazilINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 3 2009FABIANA R. VIANA Coagulase-positive Staphylococci and microbial indicators of the ,Requeijćo do Norte', a traditional semihard cheese, were surveyed in Brazil. Coagulase-positive Staphylococci were found in quantities of up to 9.4 log cfu/g. The coagulase gene was detected in isolates physiologically classified as coagulase-negative. The SEB and TSST-1 toxins were detected. Salmonella spp. were not detected. High levels of total and fecal coliforms (, 210 MPN/g) and moulds (, 6.48 log cfu/g) were found in most samples. The values of physical,chemical parameters and water activity showed the greatest variations. These results suggest a possible risk that this cheese may pose to consumers. [source] A national study on the residential impact of biological aerosols from the land application of biosolidsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2005J.P. Brooks Abstract Aims:, The purpose of this study was to evaluate the community risk of infection from bioaerosols to residents living near biosolids land application sites. Methods and Results:, Approximately 350 aerosol samples from 10 sites located throughout the USA were collected via the use of six SKC Biosamplers®. Downwind aerosol samples from biosolids loading, unloading, land application and background operations were collected from all sites. All samples were analysed for the presence of HPC bacteria, total coliform bacteria, Escherichia coli, Clostridium perfringens, coliphage, enteroviruses, hepatitis A virus and norovirus. Total coliforms, E. coli, C. perfringens and coliphage were not detected with great frequency from any sites, however, biosolids loading operations resulted in the largest concentrations of these aerosolized microbial indicators. Microbial risk analyses were conducted on loading and land application operations and their subsequent residential exposures determined. Conclusions:, The greatest annual risks of infection occurred during loading operations, and resulted in a 4 × 10,4 chance of infection from inhalation of coxsackievirus A21. Land application of biosolids resulted in risks that were <2 × 10,4 from inhalation of coxsackievirus A21. Overall bioaerosol exposure from biosolids operations poses little community risk based on this study. Significance and Impact of the Study:, This study evaluated the overall incidence of aerosolized micro-organisms from the land application of biosolids and subsequently determined that microbial risks of infection were low for residents close to biosolids application sites. [source] The microbiological quality of drinking water sold on the streets in Kumasi, GhanaLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2003K. Obiri-Danso Abstract Aim: The aim of this study was to assess the microbiological quality of Ghanaian bottled and plastic-bagged drinking water sold on the streets of Metropolitan Kumasi, Ghana. Methods and Results: Eight bottled, 88 factory-filled plastic sachet and 40 hand-filled hand-tied polythene-bagged drinking waters were examined for the presence of heterotrophic bacteria total viable counts (TVCs), indicators of faecal contamination (total coliforms, faecal coliforms and enterococci) and for lead, manganese and iron. Heterotrophic bacteria were found in all three types of water with TVCs per millilitre ranging from 1 to 460 for bottled water, 2,6·33 × 105 for factory-bagged sachet water and 2·33 × 103,7·33 × 1012 for hand-filled hand-tied bagged water. None of the microbial indicators of faecal contamination were detected in bottled water, whereas 4·5% of the factory-bagged sachets contained total coliforms and 2·3% faecal coliforms, and 42·5% of the hand-filled hand-tied bags contained total coliforms, 22·5% faecal coliforms and 5% enterococci. Iron was found in all three types of drinking water but at concentrations well within the WHO recommendations. Lead and manganese were not detected. Conclusion: Ghanaian bottled water is of good microbiological quality but some factory-bagged sachet and hand-filled hand-tied polythene-bagged drinking water are of doubtful quality. Significance and Impact of the Study: Factory-bagged sachets and hand-filled hand-tied bags of drinking water sold in Ghana should be monitored for microbiological contamination, with the aim of raising standards in the industry and re-assuring the public. [source] Microbial and nutrient pollution in the coastal bathing waters of Dar es SalaamAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue S1 2009Thomas J. Lyimo Abstract 1.The objective of the present study was to assess the microbial and nutrient quality of coastal beach waters used for bathing in the city of Dar es Salaam, Tanzania. Concentrations of traditional and alternative microbial indicators of faecal pollution and nutrients were assessed over a 1 year period (August 2005 to August 2006) using standard methods and the results were compared with the WHO water quality guidelines. 2.Faecal indicator bacteria values varied in a consistent fashion and correlated significantly with eachother, reflecting the presumed human faecal pollution. 3.The maximum counts (MPN per 100,mL) were observed on the site close to the city centre (Ocean Road) throughout the sampling period where values ranged from 1700 to>240 000 total coliform (TC), 200 to 92000 faecal coliform (FC) and 11 to 4900 enterococci (ENT). Other sites showed less predictable results with a range of values from 0,920, 0,540 and 0,46 for TC, FC and ENT, respectively. Furthermore, the faecal indicator bacteria concentration varied significantly with sampling time (P<0.05) and between sampling points (P<0.05). 4.Similarly, nutrients were significantly higher (P<0.05) at Ocean Road where concentration (µmolL,1) ranges were 0.2,54 (NO3), 0.0,20 (NO2) and 0.3,45 (PO4). 5.The levels of faecal indicator bacteria and nutrients were higher during the rainy seasons than the dry seasons, showing the inclusion of rain run-off as a source of contamination. The faecal indicator bacteria correlated positively with nutrients in both 1 year and daily data sets (P<0.01). Positive relationships were also observed among faecal indicators. This strongly suggests that an important role is played by sewage contamination in the extent of microbial pollution at the studied urbanized coastal beaches. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||