Comparison of fecal indicators with pathogenic bacteria and rotavirus in rural Bangladesh groundwater

Groundwater is routinely analyzed for fecal indicators but direct comparisons of fecal indicators to the presence of bacterial and viral pathogens are rare. This study was conducted in rural Bangladesh where the human population density is high, sanitation is poor, and groundwater pumped from shallow tubewells is often contaminated with fecal bacteria. Five indicator microorganisms (E. coli, total coliform, F+RNA coliphage, Bacteroides and human-associated Bacteroides (HuBacteroides)) and various environmental parameters were compared to the direct detection of waterborne pathogens by quantitative PCR in groundwater pumped from 50 tubewells. Rotavirus was detected in groundwater filtrate from the largest proportion of tubewells (40%), followed by Shigella (10%), Vibrio (10%), and pathogenic E. coli (8%). Spearman rank correlations and sensitivity-specificity calculations indicate that some, but not all, combinations of indicators and environmental parameters can predict the presence of pathogens. Culture-dependent fecal indicator bacteria measured on a single date did not predict bacterial pathogens, but annually averaged monthly measurements of culturable E. coli did improve prediction for total bacterial pathogens. F+RNA coliphage were neither correlated nor sufficiently sensitive towards rotavirus, but were predictive of bacterial pathogens. A qPCR-based E. coli assay was the best indicator for the bacterial pathogens, rotavirus and all pathogens combined. Since groundwater cannot be excluded as a significant source of diarrheal disease in Bangladesh and neighboring countries with similar characteristics, the need to develop more effective methods for screening tubewells with respect to microbial contamination is necessary.

(Supplemental Table 2) Plant characteristics, GHG fluxes, and soil chemical and microbial properties in experimental treatments in Alexandra Fiord

We evaluated above- and belowground ecosystem changes in a 16 year, combined fertilization and warming experiment in a High Arctic tundra deciduous shrub heath (Alexandra Fiord, Ellesmere Island, NU, Canada). Soil emissions of the three key greenhouse gases (GHGs) (carbon dioxide, methane, and nitrous oxide) were measured in mid-July 2009 using soil respiration chambers attached to a FTIR system. Soil chemical and biochemical properties including Q10 values for CO2, CH4, and N2O, Bacteria and Archaea assemblage composition, and the diversity and prevalence of key nitrogen cycling genes including bacterial amoA, crenarchaeal amoA, and nosZ were measured. Warming and fertilization caused strong increases in plant community cover and height but had limited effects on GHG fluxes and no substantial effect on soil chemistry or biochemistry. Similarly, there was a surprising lack of directional shifts in the soil microbial community as a whole or any change at all in microbial functional groups associated with CH4 consumption or N2O cycling in any treatment. Thus, it appears that while warming and increased nutrient availability have strongly affected the plant community over the last 16 years, the belowground ecosystem has not yet responded. This resistance of the soil ecosystem has resulted in limited changes in GHG fluxes in response to the experimental treatments.

Supplemental Data - Bioremediation of polluted air from an industrial plant using rotating biofilter reactor-based technology

Two microbial isolates (HDB, Hydrogen-Degrading Bacteria) obtained from industrial wastewater were inoculated into the rotating biofilter reactor 'Biowheel 2.0' and tested for the ability to purify gaseous flows containing benzene and non-methane volatile organic compounds (NMVOCs) released at an industrial plant. Different classes of gaseous flow were tested, namely 'cold box', 'in shell', and 'mix', all of them associated with the industrial process of 'mold-casting'. A significant increase in Removal Efficiency (RE) was recorded for benzene and NMVOCs in the inoculated 'Biowheel 2.0' biofilter, compared to uninoculated control. For each type of gaseous flow, odor impact was evaluated in the inlet and outlet flows at the industrial plant, using the test panel method and electronic nose technology. A significant drop in the amount of Olfactometric Units (O.U.) m-3 occurred in the gaseous flows treated with the bacterial consortium. The reported data demonstrate the ability of the consortium to degrade hydrocarbons, revealing its potential for bioremediation of polluted air emissions occurring at industrial plants.