Traced bacteria, scientist says
Posted on Friday, February 22, 2008
URL: http://www.nwanews.com/adg/News/217520/
TULSA — An attorney for Springdale-based Tyson Foods Inc. pecked away Thursday at the testimony of a Florida biology professor who says she’s the first person to track bacteria from poultry houses to streams.
Jody Harwood stood her ground in U. S. District Court as Jay Jorgensen questioned her ability to find a “biomarker” that proves high levels of bacteria found in poultry houses reach the Illinois River and pose a threat to human health.
Harwood works at the University of South Florida in Tampa, and most of her research is in what’s known as microbial source tracking. It’s a way to determine the source of fecal bacteria, tracking it from point A to point B, she said.
Harwood said she tracked a fecal bacteria biomarker, finding it in poultry houses, in fields where poultry litter was spread, in nearby ditches, in groundwater and in rivers. She analyzed 200 samples of water, soil and poultry litter to reach her conclusions.
“My opinion is that the land application of poultry waste is a major contributor to bacteria levels in the Illinois River watershed,” Harwood testified.
Thursday was the third day in a seven-day hearing in which Oklahoma Attorney General Drew Edmondson seeks a preliminary injunction to ban farmers from spreading poultry litter on fields in the watershed.
The hearing is part of the lawsuit filed by Edmondson in 2005 against eight poultry companies that operate in the watershed. Edmondson accuses the companies of polluting the watershed with poultry litter.
The companies sued are Tyson Foods; Simmons Foods of Siloam Springs; Cargill Inc. of Minneapolis; Cobb-Vantress Inc. of Siloam Springs; George’s Inc. of Springdale; Peterson Farms Inc. of Decatur; Willow Brook Foods of Springfield, Mo.; and Cal-Maine Foods Inc. of Jackson, Miss.
About half of the 1 million acre watershed is in eastern Oklahoma. The rest is in Benton and Washington counties in Arkansas.
Harwood compared microbial source tracking to DNA used as evidence by police and courts to determine a person’s guilt or innocence.
“It’s essentially the same type of methodology,” she said.
Later, she said there is “no standard for detecting poultry waste,” and that she’s developed the bacteria biomarker to do it.
Jorgensen questioned the reliability of microbial source tracking, referring to it as “novel,” “ revolutionary” and “cutting edge.” Harwood in court said she disliked the words, but Jorgensen showed an e-mail sent by Harwood to another state expert in which she called the tracking “novel.”
“You can say you own it,” Jorgensen told Harwood.
“I don’t own it,” she said. “It’s science. I want it out.”
Jorgensen used a cartoon on a video screen to illustrate a point about the difficulty in tracking poultry litter.
The cartoon showed poultry litter coming out of the red barn in a truck that carried it to a green farm field, but just to the right of the field were cows, deer, horses, birds, geese ducks and pigs standing near a blue stream. Jorgensen asked whether the other animals could lead to some of the bacteria found in the streams, and could carry the biomarker. Harwood said the biomarker was found in one duck among 10 samples. It was found in one goose among 10 tested, but other animals didn’t carry the biomarker, she said.
Harwood said chickens and turkeys produce more waste than the other animals shown.
“We chose the [animals ] that are most likely to impact the watershed,” she said. “We targeted the ones that are going to be major contributors.”
While most of the day focused on Harwood, Oklahoma also had Lowell Caneday, an Oklahoma State University leisure studies professor, describe recreational activities in the river.
The state contends poultry litter poses a threat to human health and lists it as the key reason for banning poultry litter spreading from farms.
Caneday said an average of 117, 685 people floated the Illinois in canoes, kayaks and inner tubes in each of the past four years.
Floating increases the exposure to river water, and floaters rarely take showers after leaving the river, he said.
“I’d never leave the river without showering,” Caneday testified. “Knowing the history of that river, I don’t want that on my body.”
Scott McDaniel, a Tulsa attorney who represents Peterson Farms, said Caneday exaggerated when estimating that those using the river have 622, 220 hours of contact with water in the watershed.
Caneday said floaters spent about four hours each on the river, but he couldn’t say how much time was spent in the water.
He also couldn’t estimate how many hours are spent in the water by those who picnic, fish or pursue other recreation at the river.
“You aren’t offering the opinion that these people are doused with pathogenic bacteria, are you ?” McDaniel asked.
“That’s right,” Caneday said.
Testimony by witnesses for Oklahoma is expected to continue at 8: 30 a. m. today at the U. S. District Courthouse in Tulsa. Attorneys for the poultry companies will begin their case once the state is done.