Variability in 24 hour excretion of cyanuric acid: implications for water exposure assessment.
Cyanuric acid (CYA) excretion in urine has been used to estimate the volume of water ingested during swimming and other recreational activities in outdoor pools containing this chemical. These estimates of water ingestion are based on the assumption of 100% excretion within 24 hours, but the supporting evidence for this is scant. While adapting this methodology to investigate other water ingestion scenarios, we observed a high degree of variability in cyanuric acid excretion among experimental subjects, with over 25% of individuals excreting less than 80% of an ingested dose. Use of cyanuric acid to measure inadvertent water ingestion may be a valuable tool to generate data for health risk assessment of non-potable water sources, but our observations indicate that this technique carries an inherent degree of underestimation that should be taken into account when calculating water exposure.
Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, VIC 3004, Australia E-mail: martha.sinclair@monash.edu.
Martha
M
Sinclair
School of Civil, Environmental and Chemical Engineering, RMIT University, 124 La Trobe Street, Melbourne, VIC 3001, Australia.
Felicity
F
Roddick
School of Civil, Environmental and Chemical Engineering, RMIT University, 124 La Trobe Street, Melbourne, VIC 3001, Australia.
Stephen
S
Grist
School of Civil, Environmental and Chemical Engineering, RMIT University, 124 La Trobe Street, Melbourne, VIC 3001, Australia.
Thang
T
Nguyen
Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, VIC 3004, Australia E-mail: martha.sinclair@monash.edu.
Joanne
J
O'Toole
Department of Epidemiology and Preventive Medicine, Monash University, The Alfred Centre, 99 Commercial Road, Melbourne, VIC 3004, Australia E-mail: martha.sinclair@monash.edu.
Karin
K
Leder
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013551:Swimming Pools; D013997:Time Factors; D014227:Triazines / Q000493:pharmacokinetics / Q000652:urine*; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics / Q000652:urine*; D060753:Water Quality
D014227:Triazines; D014874:Water Pollutants, Chemical; C004632:cyanuric acid