Tác nhân gây bệnh trong đất và thực vật Giới thiệu văn học sớm xử lý ứng dụng đất của nước thải, nước thải, hoặc chất rắn bùn thải thấp (Sepp, 1971). Văn học lo ngại về việc sử dụng nước thải thô, có thể dẫn đến nhiễm trùng động vật hoặc sức khỏe con người (Bicknell, năm 1972, Dunlop et al, 1951;. Dunlop và Wang, 1961). Hiện nay, việc thực hành của việc áp dụng nước thải không được điều trị hoặc bùn đều bị cấm. USEPA 503 quy định cho phép ứng dụng đất của các chất rắn sinh. | CHAPTER 8 Pathogens in Soils and on Plants INTRODUCTION The early literature dealt with land application of sewage effluent or low-solids sewage sludge Sepp 1971 . This literature raised concerns about the use of raw sewage which could result in animal or human health infections Bicknell 1972 Dunlop et al. 1951 Dunlop and Wang 1961 . Currently the practice of applying untreated sewage or sludge is prohibited. The USEPA 503 regulations allow land application of biosolids treated sewage sludge either as Class A or Class B material see Chapter 11 on Regulations . The existence of pathogens in soils and on plants depends on their survival of the wastewater treatment processes and biosolids treatment method of land application soil conditions and environmental conditions. Although many of the biosolids processes can result in very effective disinfection and the application of these biosolids does not represent a health hazard public perception may be sufficiently significant so that applying biosolids to certain food chain crops must be avoided. Figure shows the potential routes of pathogen transmission to humans and animals. Food chain crops that are cooked or processed would have no potential for infection. These would include crops for oil soybeans sunflower and canola or canned foods. Food crops that would not come in contact with biosolids such as fruit trees citrus nut pears apples etc. would also not harbor pathogens and would not be a potential source of infection. Nonfood chain crops such as fiber cotton or forest would also not present a hazard to humans or animals. Although Class B biosolids can contain pathogens USEPA provided site restrictions to preclude potential impact to human and animal health and environmental consequences. These site restrictions were based on the potential survival of pathogens in the environment. When low-solid biosolids are applied by spraying on land the potential exists for pathogens to be aerosolized. Workers in particular
