David L. Lewis, Ph.D.
1310 Saxon Road
Watkinsville, GA 30677 USA
Cellular: 706 296 3675
Email: LewisDaveL@aol.com; DavidL@uga.edu
Neural Dynamics Research Group
University of British Columbia
828 W. 10th Ave, Vancouver, BC,V5Z 1L8
Director, Research Misconduct Project
National Whistleblowers Center
3238 P Street, NW
Washington, DC 20007
The article promoting composted sewage sludge as safe for children to play in, "Athens children play with worms, learn about composting" (May 7), is irresponsible and factually incorrect. Studies published in the peer-reviewed scientific literature demonstrate that persistent environmental pollutants, which are commonly found in treated sewage sludges and are not broken down by composting, become concentrated in earthworms. A Swedish study published in 2005, for example, found that flame retardants banned in Europe because of their developmental effects on children accumulate to high levels in earthworms feeding on sewage sludges - also called "biosolids." A 2010 study found that verbal and IQ scores in children exposed to these pollutants were reduced as much as 5.5 to 8.0 points.
The article promoting the safety of Athens-Clarke County's compost also claims that there is "no trouble with traces of metal or pathogens within the sludge because of required testing." Based on a national survey of sewage sludges conducted in 1988, EPA only requires testing nine metals. But when EPA repeated the survey in 2009, it found a total of 27 metals in most if not all sewage sludges. This includes highly toxic metals such as thallium, which were rarely found in the 1988 survey upon which EPA's regulation is still based. With regard to pathogens, EPA only requires testing for one or more indicator organisms that are easily destroyed by sewage treatment processes. It does not require testing for most disease-causing bacteria, viruses and parasites that survive treatment processes such as composting.
In 2002, my coworkers and I at EPA and UGA documented illnesses and deaths linked to biosolids at land application sites across the U.S. and Canada. Others have since independently confirmed our results. Many of the same skin, respiratory and gastrointestinal problems we observed are also prevalent among residents living in the Dunlap Road community where Athens-Clarke County stockpiles and composts its sewage sludge. Although technologies for greatly reducing these adverse effects are available, Athens-Clarke County chooses to ignore the sufferings of this community and mislead the public concerning the safety of its composted sewage sludge.
David L. Lewis