title: Measuring water ingestion from spray exposures.
abstract: Characterisation of exposure levels is an essential requirement of health risk assessment; however for water exposures other than drinking, few quantitative exposure data exist. Thus, regulatory agencies must use estimates to formulate policy on treatment requirements for non-potable recycled water. We adapted the use of the swimming pool chemical cyanuric acid as a tracer of recreational water ingestion to permit detection of small water volumes inadvertently ingested from spray exposures. By using solutions of 700-1000 mg/L cyanuric acid in an experimental spray exposure scenario, we were able to quantify inadvertent water ingestion in almost 70% of participants undertaking a 10 min car wash activity using a high pressure spray device. Skin absorption was demonstrated to be negligible under the experimental conditions, and the measured ingestion volumes ranged from 0.06 to 3.79 mL. This method could be applied to a range of non-potable water use activities to generate exposure data for risk assessment processes. The availability of such empirical measurements will provide greater assurance to regulatory agencies and industry that potential health risks from exposure to non-potable water supplies are well understood and adequately managed to protect public health.
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, Vic, 3004, Australia. Electronic address: martha.sinclair@monash.edu.
authors.forename: Martha
authors.initials: M
authors.lastname: Sinclair
authors.affiliation: School of Civil, Environmental and Chemical Engineering, RMIT University, 124 La Trobe Street, Melbourne, Vic, 3001, Australia. Electronic address: felicity.roddick@rmit.edu.au.
authors.forename: Felicity
authors.initials: F
authors.lastname: Roddick
authors.affiliation: School of Civil, Environmental and Chemical Engineering, RMIT University, 124 La Trobe Street, Melbourne, Vic, 3001, Australia. Electronic address: thang.nguyen@rmit.edu.au.
authors.forename: Thang
authors.initials: T
authors.lastname: Nguyen
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, Vic, 3004, Australia. Electronic address: joanne.otoole@monash.edu.
authors.forename: Joanne
authors.initials: J
authors.lastname: O'Toole
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, Vic, 3004, Australia. Electronic address: karin.leder@monash.edu.
authors.forename: Karin
authors.initials: K
authors.lastname: Leder
mesh_terms: D006801:Humans; D059027:Recycling; D013551:Swimming Pools; D014867:Water; D014874:Water Pollutants, Chemical; D014881:Water Supply
chemical_list: D014874:Water Pollutants, Chemical; D014867:Water
keywords: Cyanuric acid; Exposure assessment; Recycled water; Sprays; Water reuse