title: Minimizing health risks during secondary effluent application via subsurface drip irrigation.
abstract: Health risks posed on consumers due to the use of agricultural products irrigated with reclaimed wastewater were assessed by numerical simulation. The analysis is based on defining of an Exposure Model (EM) which takes into account several parameters: (i) the quality of the applied wastewater, (ii) the irrigation method, (iii) the elapsed times between irrigation, harvest, and product consumption, and; (iv) the consumers' habits. The exposure model is used for numerical simulation of human consumers' risks by running the Monte Carlo simulation method. Although some deviations in the numerical simulation which are probably due to uncertainty (impreciseness in quality of input data) and variability due to diversity among populations reasonable results were accepted. Accordingly, there is a several orders of magnitude difference in the risk of infection between the different exposure scenarios with the same water quality. The variability indicates the need for setting risk-based criteria for wastewater reclamation, including the application method and environmental conditions, rather than single water quality guidelines. Extra data is required to decrease uncertainty in the risk assessment. Future research needs to include definite acceptable risk criteria, more accurate dose-response modeling, information regarding pathogen survival in treated wastewater, additional data related to the passage of pathogens into and in the plants during irrigation, and information referring to the consuming habits of the human community.
authors.affiliation: J. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Kiryat Sde Boker 84990, Israel. gidi@bgu.ac.il
authors.forename: Gideon
authors.initials: G
authors.lastname: Oron
authors.forename: Lieonid
authors.initials: L
authors.lastname: Gillerman
authors.forename: Avraham
authors.initials: A
authors.lastname: Lael
authors.forename: Yossi
authors.initials: Y
authors.lastname: Manor
authors.forename: Erez
authors.initials: E
authors.lastname: Braude
authors.forename: Amos
authors.initials: A
authors.lastname: Bick
mesh_terms: D057914:Agricultural Irrigation / Q000379:methods*; D005638:Fruit; D008962:Models, Theoretical; D009010:Monte Carlo Method; D012307:Risk Factors; D012987:Soil / Q000737:chemistry; D014675:Vegetables; D014865:Waste Disposal, Fluid / Q000379:methods*; D014866:Waste Products / Q000009:adverse effects*; D014873:Water Pollutants / Q000009:adverse effects
chemical_list: D012987:Soil; D014866:Waste Products; D014873:Water Pollutants