Swimming in chemicals?

Across America, more than 7 million pool owners are starting to prepare their concrete ponds for the summer season.

If you're one of them, have you thought about how you're disinfecting the pool's water? Traditionally, chlorine is the main ingredient used to keep nasty bacteria at bay.

However, Ideal Bite notes that chlorine levels in pools are commonly be 200 to 400 times higher than what's considered safe for the environment.

What's worse, E Magazine points out that this same chemical that cleans up the water also reacts with our skin to create toxic chloramines and trihalomethanes.

European studies have found that lifeguards at chlorinated pools have higher rates of asthma. The New York Times reports that long-term studies discovered a link between indoor pools and childhood asthma. The Green Guide refers to a study from the American Journal of Respiratory and Critical Care Medicine, which connects swimming pool chlorine to decreased lung function in children.

So how do you swim in the backyard without getting sick? As with many things, moderation is the key. Over-chlorination and overexposure seem to be the biggest problems.

• Skip indoor pools -- chemical fumes get trapped inside, and this is especially harmful to children.
• Shower right before you swim -- sweat, deodorant, and lotions can react with chlorine.
• Avoid cloudy pool water -- it's a sign the chemicals may be out of whack.
• Keep out if you can smell a strong chlorine scent -- that's too much chlorine!
• Swim when the pool is least crowded -- the more people, the more chemical reactions.

For your pool at home, consider adding an ionizer to the mix. This device helps disinfect the water so you can use less chlorine. Check out the useful buying guide from eHow.

While there are non-chlorine "eco-friendly" pool cleaners on the market, The Green Guide comments that the effectiveness of these products hasn't been tested by a reliable third party like Consumer Reports or the Consumer Product Safety Commission.

For now, just be careful with the amount of chlorine you use. Test your water frequently with any of the reliable kits or test-strips available -- that's how you'll know if you're using too much or too little. And don't use chlorinator tablets because these usually have very high concentrations of chlorine.

The Practical Environmentalist has more tips for keeping your pool "green" (but not in an algae-forming way!). For example, use a pool cover to conserve heat and reduce water evaporation, and look for a water- and energy-saving pool filter system.