Prof. Murray McBride, Cornell University
"Agricultural soils are a unique and valuable resource. Protecting agricultural soils requires anticipating and avoiding potential harms since once contaminated with persistent pollutants, the damage will remain for the foreseeable future. Once contaminated, stopping the application of pollutants such as metals and many organic chemicals that are in sewage biosolids will not correct the problem. The contamination will remain for decades or centuries. It is thus critical to prevent this essentially permanent degradation"
"Livestock that graze on sludge-amended pastures ingest biosolids that adhere to the forage plants and also ingest soil directly. Particularly in arid conditions, soil can be up to 18% dry weight of a grazing animal’s diet. Even where lesser amounts are ingested, recent research has shown impacts to grazing animals from biosolids additions to soils. These impacts include an accumulation of toxic metals in edible body organs, with implications for the human food chain. Additionally, endocrine disruption (reduced testis size) has been documented, with implications for livestock reproduction. There is now evidence that elements in sludge, particularly molybdenum and sulfur, are readily taken up by forages and can lead to Cu deficiency in livestock. "
"All sewage biosolids contain an array of synthetic organic chemicals. An array of pharmaceuticals was found in all of the biosolids tested, regardless of the type of treatment. All biosolids are “highly enriched” in organic wastewater contaminants. Some are present in high concentrations in sewage biosolids (up to 1% by dry weight). Some have demonstrated toxicity. Pharmaceuticals are designed to be biologically active at very low concentrations and thus even at trace levels they may impact plants and animals. There is new information showing that antibiotics and other pharmaceuticals have an impact on plants grown in soils containing these chemicals."
"Recent studies have confirmed that the use of antimicrobials had created a large pool of antibiotic-resistance genes in bacteria that are detected in sewage sludge and effluent from sewage treatment plants. Antibiotic resistant bacteria were found in higher numbers downstream of sludge-treated farmland as compared to upstream"
"The potential for prions that might be present in wastewater to accumulate in sludges and to persist through treatment is a concern."
"Soil microorganisms play a critical role in the functions of soil as a source of plant nutrition and in the cycling of nutrients. Recent research shows that sludge application changes the soil microbial community and decreases its diversity. A number of human-use compounds (such as triclosan found in many personal care products such as antibacterial soaps) bioconcentrate in earthworms where soil has been amended with sewage sludges."
Prof. Jordan Peccia- Yale University
"Land application is often accompanied by strong odors, and biosolids contain heavy metals, hazardous organic chemicals, microbial pathogens, and antibiotic resistant bacteria."
"Sludge is a record of what society excretes. This includes any pathogen that is contained in human feces, urine, and vomitus. A recent study found more than 27 different forms of human viruses in the sewage sludges of five large U.S. cities, ranging from Adenovirus to Corona virus to HIV."
"Metals and organic chemicals that resist biological mineralization can sorb to solid particles and also accumulate in sludge. These include polybrominated flame retardants, pharmaceuticals like Prozac and Tagamet, human hormones such as estrogen, antibiotics, narcotics including cocaine, and the metabolites of these compounds."
Dr. Sierra Rayne
"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 ... Governments are playing Russian roulette with sewage sludge. Over time, there is a high probability this game will be lost at the public's expense."
Brian Bienkowski, Scientific American - May 12, 2014
"Sewage sludge used as fertilizer on farms can leave traces of prescription drugs and household chemicals deep in the soil, according to a new study by federal scientists. The findings suggest that the widespread use of biosolids could contaminate groundwater near farms with a variety of chemicals, including anti-depressants such as Prozac and hormone-disrupting compounds in antibacterial soaps."
"The researchers looked for 57 “emerging” contaminants that are increasingly showing up in the environment. Ten were detected in the soil at depths between 7 and 50 inches 18 months after the treated sludge was applied. None was in the field’s soil beforehand... Other studies have found hormones, detergents, fragrances, drugs, disinfectants, and plasticizers in treated sludge used as fertilizer. But this is the first study to show how they can persist and move in soil."
Author Lidia Epp (manager of the Molecular Core Lab in the Biology Department of College of William and Mary in Williamsburg)
"There is little doubt that there are direct human health consequences of land application of sludge. Several published public health reports clearly link the sludge application sites to the overall decline of health by the surrounding communities. Czajkowski et al in a publication from 2010 “Application of GIS in Evaluating the Potential Impacts of Land application of Biosolids on Human Health” concludes that there is a statistically significant increase in ill-health symptoms and diseases near the biosolids permitted fields. Exposed residents were defined as those living within the one mile radius of filed applied biosolids, the illnesses included certain respiratory, gastrointestinal and other diseases."
It is evident that the long term exposure to a host of the environmental pollutants is the foundation of many chronic conditions that are now at the epidemic levels. Rather than focusing narrowly on determination of specific sets of toxins present in biosolids from different sources – the research needs to shift to the epidemiological studies assessing the overall impact of complex mix of pollutants present in sludge.
It is true that biosolids contain beneficial elements like phosphorus, nitrogen, organic matter and trace nutrients. But the benefits derived from introducing those components to the soil via biosolids are by far overshadowed by the detrimental effects of toxins and pollutants that comprise the vast majority of the biosolids content.
Many countries adopted and implemented a new approach to the disposal of biosolids; methane production, energy source, recovery of metals and microelements. It is well past the time when we start to look at those alternatives as the only sustainable solution to the growing problem – what to do with the sludge our society produces."
Dr. David Lewis
"What a wastewater treatment plant does is clean up the water, but it takes all those chemicals, all those priority pollutants we worry about that are highly neurotoxic - they are carcinogenic, they are mutagenic (In genetics, a mutagen is a physical or chemical agent that changes the genetic material, usually DNA, of an organism and thus increases the frequency of mutations above the natural background level) - all of those are concentrated at the water treatment plant in sewage sludge. The EPA in 1978 decided that what we should do with this is put it on land. Forget the fact that sewage sludge now has every known priority pollutant in existence that we know of, it has every chemical that we don't know of - and no matter how long we live, we probably will never know the vast majority of chemicals that are out there that we are being exposed to - they will never be identified. What we do know is that they are all there in that sewage sludge!"
"So in 1988 Congress bans the ocean dumping of sewage sludges over health concerns, and the EPA starts promoting land application of sewage sludges in tons per acre on farms, forests, playgrounds, school athletic fields, and other public and private lands. (Please note that it was considered TOO TOXIC to continue with ocean disposal, but illogically, the public is supposed to believe that land disposal as somehow acceptable?! The toxic sludge is just the same - the thousands of pollutants now are to be spread on soils meant to sustain future generations!). EPA says it has nitrogen in it and phosphorus, so we'll spread it, provide it to farmers to put on their crops, golf courses, everywhere. Can you imagine this!?" None of the scientists at the EPA at the time I was working there, could imagine this. Unanimously, all the scientists working in that office did their best to stop this, but politics and industry, money, big money … had other ideas"
Dr. Caroline Snyder
"Land-applied municipal sewage sludge (biosolids) is a highly complex and unpredictable mixture of biological and chemical pollutants. Biosolids generated in our large industrialized urban centers is very likely the most pollutant- rich waste mixture of the 21st century."
Dr. Richard Honour
"Few in any governments appreciate that nearly all chronic diseases are caused by long-term exposure to low levels of environmental contaminants and pollutants. We should be trying to minimize this exposure, not amplifying it. It is time to end land disposal of Toxic Sewer sludge, and look at cleaner, greener alternatives - gasification / pyrolysis."