Food Safety Personnel Examining Beaver Lake Pathogens

Kristen Gibson, a postdoctoral associate in food science, is leading a year-long study with the support of a $21,000 grant from the Arkansas Water Resources Center, a unit of the UA System's Division of Agriculture similar to the Center for Food Safety.

The study was prompted by the closure of two swim beaches at Beaver Lake during the summer of 2010 because of the detection of elevated levels of generic Escherichia coli. The Prairie Creek beach was closed for 12 days and the War Eagle beach was closed for 22 days.

"Elevated levels of E. coli – an indicator of potential human pathogens such as pathogenic bacteria, enteric viruses and protozoan parasites – could be a health risk to those using the lake for recreational purposes," Gibson said. "Fecal contamination can originate from both direct and indirect inputs into Beaver Lake."

The current standard methods for evaluating microbial water quality use generic bacterial indicators such as the levels of total coliform, fecal coliform and E. coli. Gibson said these indicators do not provide enough information to determine the source of the fecal contamination. Identification of the source can better direct future mitigation strategies that would seek to prevent future lake closures.

The Center for Food Safety research project has been under way since July 2011. Researchers are collecting water samples twice a month from four of the nine swim beaches at the lake (including War Eagle and Prairie Creek) in collaboration with the Beaver Water District. The plan is to collect large-volume water samples from the lake over all four seasons and develop a microbial population database.

"By doing this, we can provide information to help guide recommendations and policy for protection of the Beaver Lake reservoir from microbial insults which lead to degradation of water quality and swim beach closures," Gibson said. "In addition, by targeting pathogenic microorganisms along with standard bacterial indicators, we will have a better understanding of the actual risk to public health since the presence of bacterial indicators often doesn't correlate with the presence of human pathogens.