FARMERS URGED TO USE POO
Australian farmers have been urged to more widely adopt the practice of using treated human waste to fertilise food crops.
The call has come from a British scientist who addressed a national bio-solids conference in Adelaide today.
A nationwide study has looked at the re-use cycle of food production and waste as well as the presence of pathogens in the soil.
The waste is collected, stored and refined into what is known as bio-solids.
Research has found its use can boost growth and yields in crops like wheat and canola, as well as making timber plantations more disease-resistant.
There are also environmental benefits from recycling waste and carbon off-setting.
Bio-solid use is common practice in the US and UK, but only a small number of Australian farmers do so.
Dr Stephen Smith from the Imperial College in London says the large scale use of human fertiliser would benefit the farming industry.
"They can be really comprehensibly integrated into you know, farm management and crop management practices to produce a predictable response as far as you know, agricultural productivity is concerned," he said.
ABC.
SEWAGE SLUDGE/'BIOSOLIDS' by Machaelle Small Wright
PATHOGEN RISKS FROM APPLYING SEWAGE SLUDGE TO LAND Just last month (July 2002), Environmental Science & Technology featured an excellent article by David L. Lewis and David K. Gattie: Pathogen Risks from Applying Sewage Sludge to Land. The following are excerpts from that article that I think lay out the problem with the 503 Sludge Rule and the serious health hazards that land-applied sludge poses. About EPA's 503 Sludge Rule ". . . Typically, a rule such as the 503 Rule is reviewed by EPA's Office of Research and Development (ORD) for scientific credibility. . . The 503 Rule was a notable exception. ORD scientists argued that protection of the public health and environment from chemical pollutants and pathogens in sewage sludges could not be fully assured. Nevertheless, under a court order to develop a guidance document for land application, federal rules for land application moved forward without broad support from ORD scientists . . . ". . . In the case of the 503 Rule, the ORD took the unprecedented step of refusing to concur unless a preamble was published with the rule acknowledging its scientific uncertainties. ORD's scientists recommended undertaking the comprehensive research program outlined in the preamble. However, the Office of Water has placed a low priority on funding biosolids research, and EPA met very little of its original $10 million commitment to address uncertainties. Pathogens in Sewage Sludges "EPA and others have compiled lists of various pathogenic bacteria, viruses, protozoa and parasitic worms potentially found in sewage sludges.
WHAT'S REALLY IN 'BIOSOLIDS' Remember the definition of biosolids provided in the industry packet that I quoted in the beginning section of this paper? 'Biosolids are solid, semi-solid or liquid materials, resulting from treatment of domestic sewage, that have been sufficiently processed to permit these materials to be safely land-applied.' No where in that definition of biosolids do they mention the industrial waste that is a major component of sewage sludge. In the book, Toxic Sludge Is Good for You!, the following is written about the real makeup of Class B sewage sludge: "The HarperCollins Dictionary of Environmental Science defines sludge as a 'viscous, semisolid mixture of bacteria- and virus-laden organic matter, toxic metals, synthetic organic chemicals, and settled solids removed from domestic and industrial waste water at a sewage treatment plant.' Over 60,000 toxic substances and chemical compounds can be found in sewage sludge, and scientists are developing 700 to 1000 new chemicals per year. Stephen Lester of the Citizens Clearinghouse for Hazardous Wastes has compiled information from researchers at Cornell University and the American Society of Civil Engineers showing that sludge typically contains the following toxins:
"In addition, a 1994 investigation by the U.S. General Accounting Office found that 'the full extent of the radioactive contamination of sewage sludge, ash and related by-products nationwide is unknown.' Most of the radioactive material is flushed down the drain by hospitals, businesses and decontamination laundries, a practice which has contaminated at least nine sewage plants in the past decade. . . . About the lead found in sludge: † † †
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