Lewis pointed out that numerous strains of everyday streptococcus are on everyone's skin and, typically, pose no health risk. Yet a strain of streptococcus resistant to many antibiotics is a likely killer. It is thus not particularly relevant that the numbers of microbes in processed sludge is low. Further complicating the sludge problem, according to Lewis, is the fact that microbes in sludge are likely to multiply, rather than decrease, over time, because they can feed on the high levels of organic and inorganic materials present in sludge. In addition, even if pathogenic microbes die quickly, their antibiotic-resistant qualities can transfer readily to other relatively benign microbes.
Scientists largely agree that no completely safe mechanism exists for disposing of sludge.
Many, however, say that land application of sludge should not have become federal policy without a basis in peer-reviewed scientific studies. No such studies have been conducted, and the land application policy does not have the support of a consensus of scientists and engineers. The reason we got it out of the ocean was basically an image-political type deal.