tailieunhanh - Organic Chemicals in Sewage Sludges
People of four generations ago lived at the turn of the 20th Century, before the invention and widespread use in agriculture and industry of thousands of synthetic chemicals. Those of us living in the early 21st Century inhabit a world where some of these substances – which were introduced as far back as the 1920s and employed more and more in the 1940s and '50s – have been around for decades. Now they are everywhere . . . including in the tissues of every human being on Earth. | Organic Chemicals in Sewage Sludges Ellen Z. Harrison1 Summer Rayne Oakes1 Matthew Hysell1 and Anthony Hay2 1Cornell Waste Management Institute Department of Crop and Soil Sciences Rice Hall Ithaca NY 14853 2Cornell University Department of Microbiology and Institute for Comparative and Environmental Toxicology Ithaca NY 14853 Author to whom correspondence should be sent email ezh1@ 607-255-8576 fax 607-255-8207 Supporting Information 1 and 2 are attached to this document and can also be accessed at http Abstract Sewage sludges are residues resulting from the treatment of waste water released from various sources including homes industries medical facilities street runoff and businesses. Sewage sludges contain nutrients and organic matter that can provide soil benefits and are widely used as soil amendments. They also however contain contaminants including metals pathogens and organic pollutants. Although current regulations require pathogen reduction and periodic monitoring for some metals prior to land application there is no requirement to test sewage sludges for the presence of organic chemicals in the U. S. To help fill the gaps in knowledge regarding the presence and concentration of organic chemicals in sewage sludges the peer-reviewed literature and official governmental reports were examined. Data were found for 516 organic compounds which were grouped into 15 classes. Concentrations were compared to EPA risk-based soil screening limits SSLs where available. For 6 of the 15 classes of chemicals identified there were no SSLs. For the 79 reported chemicals which had SSLs the maximum reported concentration of 86 exceeded at least one SSL. Eighty-three percent of the 516 chemicals were not on the EPA established list of priority pollutants and 80 percent were not on the EPA s list of target compounds. Thus analyses targeting these lists will detect only a small fraction of the organic chemicals in sludges. Analysis .
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