Gastrointestinal effects of water reuse for public park irrigation.

To investigate the gastrointestinal effects of employing recycled water as an irrigation source for urban public parks, we studied subjects active in parks irrigated with potable water, nonpotable water of wastewater origin, and nonpotable water of runoff origin. Wet grass conditions during activity and elevated densities of common indicator bacteria, but not exposure to nonpotable irrigation water per se, were found associated with an increased rate of gastrointestinal illness.