Timothy Sullivan, a doctor of biological sciences, testified in federal court January 12 that the state of Oklahoma has not presented scientifically sound evidence that poultry waste is the prevailing source of phosphorous pollution in the Illinois River watershed, Tulsa World reported. He gave his testimony as part of an ongoing trial in which the state of Oklahoma is seeking restitution from poultry companies for alleged poultry litter pollution.

Sullivan said that experts presented by the state have not adequately considered the contributions of human and cattle waste to phosphorous and bacterial counts in the watershed.