Source: Julie Larson Bricher, MEATINGPLACE, 2/26/18



In a recently completed research project, University of Georgia and Georgia Tech Research Institute scientists have found that the contribution of poultry processing plants to stream bacterial load may be overestimated.

The research aimed to identify and quantify the level of preexisting background indicator organisms under dry conditions in watersheds impacted by poultry processing facilities in urban heavy industrial, suburban light commercial, and rural settings.

Investigators determined the typical level of bacterial contamination found in surface water upstream from the site of a poultry processing plant. They found significant levels of coliform bacteria in streams prior to any stormwater runoff from poultry processing plants, suggesting that focused scrutiny given to poultry processing operations overemphasizes the industry’s true impact on the environment.  

According to a summary of the report, most U.S. poultry processing plants operate under state-issued National Pollutant Discharge Elimination System general stormwater permits, with specific provisions for facilities that handle live animals. These provisions include the detection of surrogate indicator bacterial organisms in surface water in the attempt to infer the potential impact an individual processing facility might have in introducing pathogenic bacteria into the environment.

Total coliforms, fecal coliforms and generic E. coli indicator bacteria are commonly used to denote the presence of fecal contamination in surface water, but research in related stormwater areas, such as urban watersheds, has continually shown weak correlations between the detection of indicator organisms and the presence of pathogenic bacteria.
Principal investigator Brian Kiepper, associate professor and extension specialist, University of Georgia, Athens, told MeatingPlace that while the detection of indicator organisms and practices to reduce their numbers in stormwater runoff will continue to be the focus for poultry processing plants in the foreseeable future, this research suggest more work is needed.

“The government regulator side argues that this is the best system we have right now,” Kiepper said, “[It] might not be great but using indicator organisms is the best we've got to work with. The private sector argues that may be true but you simply can't assign 'blame’ for specific stormwater impacts on these broad indicator organisms. 

“Fecal coliform bacteria exist in the digestive systems of all warm-blooded animals on the planet,” he continued. “So, taking a fecal coliform measurement in a river downstream of a poultry processing plant, getting a relatively high number and then assuming you can place the blame on the poultry processing plant isn't good science.”

While the indicator organism testing provided accurate numbers, this testing is not a good indicator of impact by individual sources, suggesting that a better system needs to be developed, added Kiepper. “My lab and others are working to find a way of accurately 'footprinting’ the stormwater impact from poultry processing plants,” he said. “[In other words], how can we take a water sample in a stream and determine as definitively as possible that pollutants of concern are coming from one specific source or another.”

The research was funded by USPOULTRY and the USPOULTRY Foundation. An industry summary of the Impact and Mitigation of Stormwater Runoff from Poultry Processing Plants research can be found online at the USPOULTRY website.

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