The researchers compared rates of reported health symptoms among California surfers in urban north Orange County and rural Santa Cruz County during the winters of 1998 and 1999. The urban surfers reported almost twice as many symptoms as the rural surfers in the rainy El Nio winter of 1998. During both study years, reported symptoms for both groups increased by about 10 percent for each 2.5 hours of weekly water exposure. These symptoms ranged from fever, nausea, stomach pain and diarrhea to sore throat, eye redness and skin infection This study is one of the first to quantify the health effects of ocean water by monitoring beach users from both urban and rural areas. It was led by Ryan H. Dwight of the UCI Environmental Health Science and Policy Program and Dr. Dean Baker, professor of medicine and director of the UCI Center for Occupational and Environmental Health. Study results appear in the April edition of the American Journal of Public Health.
North Orange County which includes America's "Surf City," Huntington Beach, and the popular vacation destination, Newport Beach was designated as the urban site because its watershed is in one of the most developed areas in the world and generates highly polluted runoff, which discharges primarily through the Santa Ana River. Santa Cruz County was selected as the rural site because of its cleaner coastal water quality and watershed characteristics. Both are highly popular surfing locales.