You are here:
AN OBSERVATIONAL STUDY: DETERMINATION OF THE VOLUME OF WATER INGESTED DURING RECREATIONAL SWIMMING ACTIVITIES
Citation:
EVANS, O. M., L. J. WYMER, T. D. BEHYMER, AND A. P. DUFOUR. AN OBSERVATIONAL STUDY: DETERMINATION OF THE VOLUME OF WATER INGESTED DURING RECREATIONAL SWIMMING ACTIVITIES. Presented at National Beaches Conference, Niagra Falls, NY, October 10 - 13, 2006.
Impact/Purpose:
The objectives of this research are: (1) to evaluate rapid state-of-the-art measuement methods of pathogens that may indicate the presence of fecal pollution in recreational waters (beaches); (2) to obtain, jointly with a sister laboratory (NHEERL), a new set of water quality data and related health effects data at a variety of beaches across the U.S., in both marine and non-marine waters; (3) to analyze the research data set to evaluate the utility of the tested measurement methods, the new EMPACT monitoring protocol, and the health effects data / questionnaire, in order to establish a relationship between measured pathogens and observed health effects; and (4) to communicate the results to the Office of Water in support of their efforts to develop new state and/or federal guidelines and limits for water quality indicators of fecal contamination, so that beach managers and public health officials can alert the public about the potential health hazards before exposure to unsafe water can occur.
Description:
EPA's Action Plan for Beaches and Recreational Waters describes research needs for exposure assessment related to swimming activities such as characterizing swimming populations with regard to routes and magnitudes of exposure. This includes characteristics such as the duration of time in the water, how much water is swallowed and frequency of swimming-related activities. The results from three epidemiological studies that examined the relationship between swimming-associated illness and water quality have shown that illness in children occurs at a higher rate than in adults. These differences may be the result of immature immune systems in children or differences in behavior during swimming activities. The current study examined water ingestion by swimmers in a swimming pool. Outdoor swimming pools use cyanuric acid to stabilize chlorine. Cyanuric acid is not absorbed through the skin, and if swallowed, passes through the body un-metabolized. The amount of water ingested can be calculated if the cyanuric acid concentration is known in the pool water and in a 24 hour urine specimen. About 570 individuals participated in the study, and swam at least an hour, and subsequently collected their urine over a 24 hour period. The results of the study showed that children ingested nearly twice as much water as adults. Children swallowed, on the average, about 47 ml of water per swim period, whereas adults ingested about 24 ml of water per swim period. Adult males ingested significantly more water than females, 30 ml and 19 ml, respectively. The results of this study provide the first empirical evidence of the amount of water individuals swallow during recreational swimming activities.