In the present study, an agricultural soil artificially amended with different concentrations of palm oil mill effluent was analysed to determine its impact on the soil microflora and other properties such as pH, organic matter, electrical conductivity, and mineral elements. In the polluted soils, the total heterotrophic bacteria, total heterotrophic fungi and total heterotrophic actinomycetes decreased significantly (p≤0.5) with increase in the concentration of the pollutant. The total heterotrophic bacteria and total heterotrophic fungi showed significant reduction (p≤0.5) with increase in the duration of the pollution while total heterotrophic actinomycetes showed no significance difference (p≥0.5) over the duration of pollution. Suspected bacterial isolates from the polluted soils were

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Aims:  To describe the extent of faecal pollution and point of use water treatment strategy during and after the 2004 flood in Dhaka. Methods:  A total of 300 water samples were collected from 20 different drinking water sources in Kamalapur, Dhaka city from August 2004 to January 2005. The level of faecal contamination was estimated using measurements of faecal indicator bacteria (total coliforms, faecal coliforms and faecal streptococci) and isolation of Vibrio cholerae was carried out following standard procedures. Total dissolved solids, dissolved oxygen, hardness, chloride and pH were also monitored. The efficacy of four disinfectants including Halotab, Zeoline®‐200, alum potash and bleaching powder were tested as point of use water treatment agents. The unacceptable level of contamination of total coliforms (TC), faecal coliforms (FC) and faecal streptococci (FS) ranged from 23·8% to 95·2%, 28·6% to 95·2% and 33·3% to 90·0%, respectively. The isolation rates of V. cholerae O1 and O139 were both 0·33%, and non‐O1/non‐O139 was 7·0%. Conclusion:  Water collected during and after floods was contaminated with TC, FC, FS and V. cholerae. Although alum potash, bleaching powder, Halotab and Zeoline®‐200 were all effective general disinfectants, Halotab and Zeoline®‐200 were superior to bleaching powder and alum potash against FC. Significance and Impact of the Study:  During and after floods, point of use water treatment could reduce waterborne diseases among flood‐affected people.

Microorganisms contaminating international Jet A-1 aircraft fuel and fuel preserved in Joint Hydrant Storage Tank (JHST) were isolated, characterized and identified. The isolates were Bacillus subtillis, Bacillus megaterium, Flavobacterium oderatum, Sarcina flava, Micrococcus varians, Pseudomonas aeruginosa, Bacillus licheniformis, Bacillus cereus and Bacillus brevis. Others included Candida tropicalis, Candida albicans, Saccharomyces estuari, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Cladosporium resinae, Penicillium citrinum and Penicillium frequentans. The viable plate count of microorganisms in the Aircraft Tank ranged from 1.3 (+/-0.01) x 104 cfu/mL to 2.2 (+/-1.6) x 104 cfu/mL for bacteria and 102 cfu/mL to 1.68 (+/-0.32) x 103 cfu/mL for fungi. Total bacterial counts of 1.79 (+/-0.2) x 104 cfu/mL to 2.58 (+/-0.04) x 104 cfu/mL and total fungal count of 2.1 (+/-0.1) x 103 cfu/mL to 2.28 (+/-0.5) x 103 cfu/mL were obtained for JHST. Selected isolates were re-inoculated into filter sterilized aircraft fuels and biodegradation studies carried out. After 14 days incubation, Cladosporium resinae exhibited the highest degradation rate with a percentage weight loss of 66 followed by Candida albicans (60.6) while Penicillium citrinum was the least degrader with a weight loss of 41.6%. The ability of the isolates to utilize the fuel as their sole source of carbon and energy was examined and found to vary in growth profile between the isolates. The results imply that aviation fuel could be biodegraded by hydrocarbonoclastic microorganisms. To avert a possible deterioration of fuel quality during storage, fuel pipe clogging and failure, engine component damage, wing tank corrosion and aircraft disaster, efficient routine monitoring of aircraft fuel systems is advocated.

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