Five reasons why surfers are more likely to get sick from polluted ocean water than beach goers

Any surfer who has leaned over to pick something up a few hours after surfing, only to suffer the embarrassment of having their nose drain all over the place, is a walking illustration of just how much ocean water surfers are exposed to when practicing their sport.

Here's a list of five reasons why surfers are more likely to get sick from polluted ocean water than other beach goers:

1. Surfers go to the beach & go in the ocean more than other beach goers

According to the 2001 Current Participation Patterns in Marine Recreation study, beach goers average 14 visits per year; in the same study surfers averaged 23 visits per year (Leeworthy and Wiley 2001).

Other studies in Oregon, California, and a national survey suggest surfer avidity is much higher. In Oregon, the average avidity was 77 visits/year (Stone et al. 2008). At Trestles, we found an average avidity of 109 visits/year (Nelsen et al. 2007). A pending Surf-First study found a average national avidity of 108 visits (unpublished).

2. Surfers recreate year round

Studies and common knowledge show that beach going is highly seasonal. Most visit occur during the summer months. Often more than half of the total visits occur during the 3 months of summer. In contrast, surfers tend to visit beaches and enter the water year round. In some places, surfers are the predominant beach visitor during winter months. This is significant because in the northern latitudes, winters tend to be more rainy than summer months, which increases the exposure to storm water runoff.

3. Every visit to the beach to surf results in full immersion in the ocean

According to Dwight et al. (2007) less than half of Southern California beach goers are exposed to ocean waters. And of those that are, many are not fully immersed in the water. Surfers, on the other hand, are fully immersed while surfing (see photo). This increases their exposure to pathogens if the water is polluted.

4. Surfers probably spend more time in the water on each visit

Surfers tend to surf between 1.5 and 2 hours surfing during each visit. Although I am not aware of any data, my guess is that this is longer than most beach goers spend in the water, with the exception of some kids who seem to spend the whole day in the water (especially in places where the water is warm).

5. As a result of the above, surfers ingest 10 times more water than swimmers or divers

As summarized here, surfers tend to ingest 10 times more water than swimmers or divers. To their exposure to pathogens in the water is much higher than other groups. The repeated, full and sometimes violent immersion in the ocean that surfer experience increases ingestion and water getting forced into the sinuses (thus the delayed nose drip).

Conclusion

The combination of more days of exposure, during some of the most polluted times, and more complete immersion and ingestion increases the total exposure of surfers to pathogens and therefore the odds of getting sick. So the next time your nose starts to drip, think about the quality of the ocean water that just sat in your head for the last several hours - hopefully it was clean!

The papers referenced below provide a more in-depth look at these issues.

References:

Dwight, R. H., D. B. Backer, et al. (2004). "Health Effects Associated With Recreational Coastal Water Use: Urban Versus Rural California." American Journal of Public Health 94(4): 565-567.

Dwight, R. H., M. V. Brinks, et al. (2007). "Beach attendance and bathing rates for Southern California beaches." Ocean & Coastal Management 50: 847-858.

Leeworthy, V. R. and P. C. Wiley (2001). Current Participation Patterns in Marine Recreation, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Ocean Service, Special Projects. National Survey on Recreation and the Environment 2000: 53.

Nelsen, C., L. Pendleton, et al. (2007). "A Socioeconomic Study of Surfers at Trestles Beach." Shore & Beach 75(4): 32-37.

Stone, D. L., A. K. Harding, et al. (2008). "Exposure Assessment and Risk of Gastrointestinal Illness Among Surfers." Journal of Toxicology and Environmental Health, Part A 17(24): 1603-1615.

The Cost of Poor Water Quality at Surfrider Malibu

Surfrider Beach at Malibu needs no introduction. Unfortunately, neither do the water quality problems. Malibu has been a chronically polluted beach for decades, consistently getting an "F" on Health the Bay's beach water quality report card. One of the primary culprits is over-capacity and improperly sited septic systems. For years, the City of Malibu has resisted constructing sewage systems as an anti-growth measure while polluting nearby beaches.



Thanks to a strong coalition that included the Malibu Surfing Association, Heal the Bay, Santa Monica Baykeeper and the West LA / Malibu Chapter of the Surfrider Foundation this all changed last Thursday when the LA Regional Water Quality Control Board voted to eliminate septics from Malibu and force the City to install waste water treatment systems. Read more about the outcome here and here and in the LA Times here.

$: Poor water quality is a public health burden that has costs.

Water quality contamination can cause skin rash, eye and ear infections, significant respiratory disease and Gastrointestinal (GI) illness. These illnesses have a variety of economic costs -- ranging from medical expenses to lost time at work to non-market impacts.

At Malibu, Given and Pendleton (2006) estimated that were were 25,000 to 100,000 excess GI illness (meaning above allowable level of illness at clean beaches) in Malibu due to poor water quality.

This results in $1.1 to $4.2 million in public costs annually due to illness associated with contaminated water in Malibu.

$: Clean water has benefits.

Clean water attracts more visitors who spend money (economic impacts) and clean water increase their enjoyment (consumer surplus).

Hanemann & Pendleton (2004) looked at economic benefits of improving beach water quality at Malibu Surfrider Beach by one letter grade. From a C to a B.

They showed that improving water quality at Malibu Surfrider would have two impacts on beach goers. First, the number of trips taken to Surfrider beach would increase by 1,538 visits per year.

The second major impact of an improvement in water quality is the annual consumer’s surplus of beach users improves by more than $140,000/ year.

In addition, the total economic impact (local spending) would increase by $45,000/year.

These are the benefits for one grade. The benefits would be much higher for a 3 or 4 grade level improvement (F to B/A)*.

*The model is nonlinear so you cannot use these figures to extrapolate directly.

These studies show that improving the water quality in Malibu will reduce the high public welfare burden associated with poor water quality and result in increased visits, increased societal benefits (consumer surplus benefits) and increase economics impacts (spending associated with beach visits).

You can read more detail and see the references in my testimony here.

Study: Surfers ingest 10 times more water than swimmers, divers

A new study has found that surfers may unintentionally ingest 10 times more water than swimmers or divers, putting them at higher risk of contracting gastrointestinal illnesses when surfing in contaminated waters.

The study, which may be the first of its kind, was conducted by scientists at Oregon State University and the Oregon Department of Environmental Quality. It also suggests that because water quality at Oregon beaches is significantly better than more popular surfing destinations, such as California, Hawaii, or Florida, the risk of GI illness is lower for people surfing the frigid waters of the Oregon coast.

“While the risk for Oregon surfers is not high for GI illness, our findings suggest that surfers who spend longer periods of time in recreational waters, or who surf in more contaminated locations, are likely to be at higher risk of contracting GI illnesses,” said David Stone, an assistant professor in the OSU Department of Environmental and Molecular Toxicology.

The study, funded by Oregon Sea Grant, used a Web-based survey to collect voluntary responses from 520 of the estimated 12,000 surfers in Oregon. Participants estimated the amount of water they ingest during a typical recreational day, and the researchers used historic water quality data collected at six popular surfing beaches to calculate the risk of infection from fecal bacteria using enterococci as an indicator organism.

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