A day at the beach — sun, sand and outdoor fun. A healthy pasttime, unless you are exposed to pollution.

Every coastal state, including those along the Great Lakes, has been affected by poor water quality. In 2005, beach pollution prompted a record 20,397 closing and swimming advisory days at ocean, bay and Great Lakes beaches.

The problem is most dangerous for small children, elderly people, pregnant women and those with weakened immune systems. They are the most likely to get sick from swimming in contaminated beachwater.

The most common causes of bacterial pollution are dirty runoff and stormwater, sewage spills and overflows.

Rain also contributes to beachwater pollution. Heavy rain can overwhelm sewage systems, forcing rainwater and raw sewage directly into coastal waters, bypassing treatment plants. And as rainwater washes over land, it picks up contaniments and boosts the amount of polluted runoff that reaches coastal areas.

To lessen your chances of getting sick:

• Swim only at beaches where waters are tested at least weekly.
• Stay out of the water when there are closings or advisories.
• Avoid beaches with nearby discharge pipes or urban beaches after a heavy rainfall.
• Stay out of murky or foul-smelling water.
• Avoid the water when you have an open wound or infection.
• Swim without putting your head underwater.

If you think you've been exposed to contaminated water:

• Rinse off well with soap and water.
• Thoroughly clean any skin abrasions.
• Use a mouthwash or clean water to gargle and spit out.
• Dry out your ears.
• Wash swimsuits and towels (and other wet clothing) as soon as possible.
• If you start to feel sick, go to your healthcare provider and tell him or her that you may have been exposed to contaminated water. Ask your doctor to report your illness to your county health department.