Comparison of ultraviolet light-emitting diodes and low-pressure mercury-arc lamps for disinfection of water.

Ultraviolet (UV) light-emitting diodes (LEDs) emitting at 260 nm were evaluated to determine the inactivation kinetics of bacteria, viruses, and spores compared to low-pressure (LP) UV irradiation. Test microbes were Escherichia coli B, a non-enveloped virus (MS-2), and a bacterial spore (Bacillus atrophaeus). For LP UV, 4-log10 reduction doses were: E.

The Gillings Sampler--an electrostatic air sampler as an alternative method for aerosol in vitro exposure studies.

There is growing interest in studying the toxicity and health risk of exposure to multi-pollutant mixtures found in ambient air, and the U.S. Environmental Protection Agency (EPA) is moving towards setting standards for these types of mixtures.

Inactivation of Escherichia coli O157:H7 during thermophilic anaerobic digestion of manure from dairy cattle.

Inactivation of the pathogenic Escherichia coli serotype O157:H7 and a non-pathogenic E. coli strain isolated from dairy cattle manure was evaluated with batch tests at 50 and 55 degrees C in biosolids from a thermophilic anaerobic digester treating the manure. Using differential-selective plating on sorbitol-MacConkey (SMAC) agar to quantify E.

Laboratory evaluation of thermophilic-anaerobic digestion to produce Class A biosolids. 2. Inactivation of pathogens and indicator organisms in a continuous-flow reactor followed by batch treatment.

Thermophilic-anaerobic digestion in a single-stage, mixed, continuous-flow reactor is not approved in the United States as a process capable of producing Class A biosolids for land application. This study was designed to evaluate the inactivation of pathogens and indicator organisms in such a reactor followed by batch treatment in a smaller reactor. The combined process was evaluated at 53 degrees C with sludges from three different sources and at 51 and 55 degrees C with sludge from one of the sources.

Laboratory evaluation of thermophilic-anaerobic digestion to produce Class A biosolids. 1. Stabilization performance of a continuous-flow reactor at low residence time.

There is increasing interest in the United States in producing biosolids from municipal wastewater treatment that meet the criteria for Class A designation established by the U.S. Environmental Protection Agency.

Inactivation of Ascaris suum and poliovirus in biosolids under thermophilic anaerobic digestion conditions.

There is considerable interest in the United States in production of Class A (low pathogen content) biosolids from the treatment of municipal wastewater sludge. Current requirements imposed by the U.S.