Those envisioning July 4 celebrations at the beach may be swimming at their own risk according to a new study that found the number of beach closures nationwide due to dirty water soared last year.
The Natural Resources Defense Council, which released its annual report Wednesday, found that beach closures and advisories across the country increased by 29 percent in 2010 compared to a year earlier. The conservation group used data from 3,000 locations nationwide and found that waters in Louisiana, Ohio, Indiana and Michigan had the highest levels of contamination.
"It's a summer rite of passage," said David Beckman, a senior attorney who directs the nonprofit's water program. "Unfortunately it can also make you sick."
Most bacterial contamination occurs during winter, when heavy rains overload storm drains and sewage systems, washing waste into the sea. Swimming in such pollution can cause gastrointestinal, respiratory and other illnesses and is of particular risk for children and the elderly, whose immune systems are weaker.