عنوان مقاله [English]
نویسندگان [English]چکیده [English]
: The reuse of sludge in agriculture leads to the transfer of some pollutants into food chain, thus hazarding the public health. The pathogens, heavy metals and nutrients in the sewage sludge from two wastewater treatment plants in Tehran-Iran, Shahid Mahallati and Ekbatan, were investigated in three independent samplings. Moreover, the reduction of pathogens after irradiation by 10kGy gamma ray from 60Co was studied. The obtained results indicated that the heavy metals and nutrients in both of the wastewater treatment plants comply with Environmental Pollution Agency Standards and the pathogens counts reduced to the extent of the permitted level after irradiation. Viable Ascaris eggs in Ekbatan sludge was more than permitted level even after irradiation. According to the obtained data, just the sewage sludge of Shahid Mahallati treatment plant produced class A biosolids by irradiation which means that it can be applied to the agricultural lands, public contact sites and even home gardens. The odor of irradiated samples reduced as compared with the control ones. Vector attraction reduction processes must be conducted before use. The capability of the mentioned dose of gamma ray in converting the municipal sewage sludge into a sanitary fertilizer, depends on the microbial contamination level, specially the numbers of viable Ascaris eggs.
 U.S. Environmental Protection Agency. Office of Research and Development. Environmental Regulations and Technology, Control of Pathogens and Vector Attraction in Sewage Sludge. Cincinnati, OH (USA): Center for Environmental Research Information (2003).
 H.W. McKinnon, Environmental Regulation and technology, control of pathogens and vector attraction in sewage sludge (Including Domestic Septage), U.S. Environmental Protection Agency/625/R-92/013, USA (2003).
 Board of Environmental Studies and Toxicology, Biosolids applied to land: Advancing standards and practices, National Academy Press-Washington, DC (2002).
 J. Prasatsrisupab, V. Sabua, S. Tammarate, M. Pumklom, P. Chaiwanakupt, S. Srithongtim, The effects of irradiated wastewater sludge cake on maize and environment. 17th WCSS,14-21,Symposium no.59, August 2002, Paper no.735,Thailand (2002).
 I. Mohammed, AL-Ghonaiem, A.S.S. Ibrahimand, A.A. Al-Salamah, Application of Gamma irradiation in treatment of waste activated sludge to obtain class a biosolids. Am. J. Env. Sci. 6(6) (2010) 500-504.
 G. Yehia, M. Galal, Recycling of Treated Sewage Sludge in Sustainable Agriculture. Arab J. Nuc. Sci. Appl. 45(2) (2012) 548-560.
 M.D. Kumar, Environmental Pollution and waste Management. M D Publications PVT LTD. New Delhi. (1998).
 ASTM, Standard practices for digestion of water samples for determination of metals by flame atomic absorption, graphite furnace atomic absorbtion, plasma emission spectroscopy or plasma mass spectrum, 11(1) (2007).
 EURO CHLOR Analytical, Determination of Mercury in liquids (2009).
 ISO 7251, Microbiology of food and animal feeding stuff- Detection and enumeration of presumptive Escherichia coli- Most probable number technique (2005).
 ISO 4831, Microbiology of food and animal feeding stuff- Horizontal method for the detection and enumeration of coliforms Most probable number technique, (2006).
 ISO 6579, Microbiology: General guidance on methods for the detection of Salmonella, (1993).
 ISO 6340, Water quality- Detection and enumeration of Salmonella, (1995).
 J.M. Solera, Manual of sampling and analysis of wastewater, GEA, University Miguel Hernandez, (2006).
 M. Pirsaheb, M.K. Sharifi, Survey of parasitic contamination of raw wastewater produced in Islamabad-e-Gharb and role of stabilization ponds in removing this contamination. Zahedan J. Res. Med. Sci. 13(5) (2011) 51.
 M.R. Ayres, M.D. Dunvan, Analysis of wastewater for use in agriculture- A lab manual of parasitological and bacteriological techniques, World Health Organization, Geneva, (1996).
 A.S. Lepeuple, G. Garel, M. Jovic, M.R. Roubin, Literature review on levels of pathogens and their abatement in sludges, soil and treated biowaste, Horizontal, EU (2004).
 M.J. Malakuti, Sustainable agriculture and increase performance by optimizing the use of fertilizers in Iran, Ministry of Agriculture, (2005).
 A.J. Tree, R.M. Adams, D.N. Lees, Chlorination of indicator bacteria and viruses in primary sewage effluent. <http://aem.asm.org/ cgi/content/full/69/4/2038>( Jan.2003).