Thanks to pollution, a day at the beach can be an expensive affair. A study of two California beaches indicates that illnesses associated with swimming in contaminated waters cost the public more than $3 million annually.

Ryan H. Dwight of the University of California at Irvine and his colleagues quantified the health burden associated with swimming in polluted waters using a survey of beachgoers who reported whether or not they had experienced symptoms of gastrointestinal or respiratory distress, or eye, ear or skin infections after swimming. They then calculated the financial impact of such health problems for two popular Orange County, Calif., beaches--Newport and Huntington--using average salaries and medical costs for the area. All told, it costs some $3.3 million each year to treat the more than 74,000 cases linked to exposure to polluted waters, the researchers report. And because they did not factor in additional costs for self-treatment, such as remedies bought at the drugstore, the authors posit that their calculation is conservative. This estimate helps us begin to understand the bigger picture of the economic burden imposed on society from polluting our coastal recreational waters, remarks study co-author Linda Fernandez of the University of California at Riverside.

According to the report, the two main sources of pollution for the California beaches are urban runoff and sewage treatment. During the study period, both beaches had water quality levels that were within the standards set by both the Environmental Protection Agency (EPA) and the state of California. Indeed, the researchers calculate that the total public health costs would exceed $7 million annually if the coastal water quality had the maximum pollution levels allowed under EPA standards for the entire year. The ultimate value of this research is for policymakers, who are well aware of the substantial costs involved with cleaning up water pollution, but need to know the other side of the equation--the costs associated with not cleaning up the water, Dwight says. The results were published online by the Journal of Environmental Management.