205452 Climate Change and Exposure to Coastal Water Contamination

Tuesday, November 10, 2009: 12:50 PM

Jan C. Semenza, PhD, MPH, MS , Unit of Scientific Advice, European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
Mitchell Vaughn Brinks, MD, MPH , School of public health - c/o Mitch Brinks, Oregon State University, Eugene, OR
Guido Buscher, MS , Sau, ECDC, Stockholm, Sweden
Josh Caplan, MS , ESR, PSU, Portland, OR
Ryan Hamilton Dwight, PhD , Coastal Water Research Group, Huntington Beach, CA

Climate change will increase water vapor, due to higher mean temperatures, and trigger more intense precipitation events, which greatly increases the risk of pollutants entering coastal waters. Thus, bathers are at considerable risk of exposure to potentially harmful agents.


We collected water quality, beach attendance and water exposure data from all beaches in Southern California for 2000-2005. Due to the lack of independence of the observations the water quality was estimated by a linear model with a generalized least square estimator. The risk of gastrointestinal illness was calculated based on the predicted water quality for a given precipitation.


Total precipitation of 1 inch per week can be attributed to 18.63 episodes of gastrointestinal illness per 1000 bathers at one of the large rivers; in contrast beaches next to smaller rivers are less at risk of contamination during a rain event, with 9.59 episodes per 1000 bathers. Under different climate change scenarios and the size of rivers, an extrapolation to a total precipitation of 4 inches per week indicates an increase of 23% to 66% more episodes, respectively.


The analysis presented here provides estimates that will prove to be useful for policy decisions and environmental regulations under climate change scenarios. Consequences will not be restricted to the beach going public but will also extend to the tourism industry and the environment. Since global climate change will progress into the foreseeable future, strategies need to be developed to address this emerging public health concern.

Learning Objectives:
1) Describe the impacts of climate change on coastal waters 2) List the factors that influence coastal water contamination 3) Discuss different climate models for Southern California and the associate health effects from recreational water use

Keywords: Climate Change, Water Quality

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: did the research
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.