Mar 01, 2016
The land disposal of sewage sludge has resulted in significant controversy, and a resistance movement is rightfully building to this misguided policy. Quite simply, the science doesn't support the disposal of sewage sludge across the landscape. The supposed benefits are more than offset by the risks to human and environmental health.
As scientists, we have been watching the issue with increasing concern.
An unimaginably large number of chemical and biological contaminants exist in these materials, and they persist in the product up to, and after, land disposal. Scientific investigations have identified only a tiny fraction of the total contaminant load. We cannot even say with any degree of confidence what the true range of contaminant risk is from the sludge. Call it an "unknown unknown." Because of potential synergistic interactions between the contaminants in the sludge, the risks are largely unknowable.