The Government Accountability Office has requested the Environmental Protection Agency to seek more information about the levels of pollution that are discharged by factory farms. The report, available here, was released Wednesday to a House committee hearing that will examine federal oversight on factory farms, according to the Associated Press.

The EPA in December proposed a rule change that will eliminate requirements for concentrated animal feeding operations to report air emissions of hazardous substances such as ammonia and hydrogen sulfide to federal, state and local officials. According to EPA, the current rule creates an unnecessary burden for farms.

According to the GAO report, EPA does not currently have the information it needs to effectively regulate CAFOs, which have increased in number by 230 percent in the past 20 years.

Although it has been determined in the report that "some large farms that raise animals can generate more raw waste than populations of some U.S. cities produce annually," there still exists no conclusive assessment on the extent to which pollutants from CAFOs impact human health and the environment.