No abstract

This study evaluated the effect of two biocontaminant surrogates on the activity and performance of activated sludge. In the presence of bacteriophage MS2 at 3.2 × 108 PFU/ml, the peak respiration rates varied between 9.1 and 10.5 mg O2/gVSS/hr, generally similar to the rates observed in negative controls. MS2 did not alter the molar CO2‐produced‐to‐O2 consumed stoichiometry observed during respiration. Similar results were observed for Bacillus globigii (BG). Ethanol, a potential co‐contaminant associated with biocontamination incidents, can inhibit initial oxygen uptake. MS2 and BG both adsorbed to activated sludge; post‐exposure viability was confirmed for BG but not for MS2. This study is the first to evaluate the effects of BG and MS2 on activated sludge, and it presents a protocol that can be used in operational situations.