Measuring water ingestion from spray exposures. (1st August 2016)

• Record Type: Journal Article
• Authors: Sinclair, Martha; Roddick, Felicity; Nguyen, Thang; O'Toole, Joanne; Leder, Karin
• Is Part Of: Water research. Volume 99(2016)
• Page Start: 1
• Page End: 6
• Publication Date: 2016-08-01
• Subjects: Recycled water -- Water reuse -- Sprays -- Exposure assessment -- Cyanuric acid; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2016.04.034
• Languages: English
• ISSNs: 0043-1354

Abstract

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. Graphical abstract: Highlights: Acceptable exposure conditions for the tracer chemical cyanuric acid were established. Inadvertent water ingestion from spray exposure was detected in 70% of participants. Ingested volumes as low as 0.06 mL could be quantified. The methodology could be adapted to other water exposure scenarios. Exposure data will inform risk assessment and regulation of non-potable waters.