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Beware that picnic table!


Published June 14, 2002

Ah, summer. The season for lounging on the deck, for spreading a meal on a park picnic table, for watching the kids romp on the fantastic wooden playground with the spires and hidey-holes.

But wait.

The ordinary pressure-treated wood that we've been using for years is now going off the market for most home-improvement projects because of health concerns.

So what are we supposed to do with the wood still out there in our back yards? The U.S. Environmental Protection Agency didn't offer consumers much guidance in February, when it announced that the manufacturers would voluntarily take the wood off the market for most uses by Dec. 2003.

The reason for the phaseout? The wood is treated with a pesticide that - now we find out - washes out of the boards into soil and comes off on your hands when you touch it. It's chromated copper arsenate, or CCA. Both arsenic and chromium - ingredients of the pesticide - can cause cancer and other health problems. Children are especially vulnerable, because they put their hands in their mouths and their bodies are more sensitive.

"Kids should not be crawling on these decks, period," said Richard Wiles, senior vice president of the Washington, D.C.-based Environmental Working Group, which has studied the issue. "At least put a blanket down or something."

Another option: Chemical-free hardwood deck tiles, which are 16x16 inches and made for exterior use. You can attach these to your current deck. (Check out http://www.built-e.com for the tiles and other alternative products, including the super-strong wood called "ipe.")

After CCA wood is pulled from the marketplace, home improvement stores such as Lowe's and Home Depot will start carrying arsenic-free treated wood, which uses several copper-based pesticides. Some of the trade names are NatureWood, Preserve, Preserve Plus and Wolmanized NaturalSelect. These new treated woods pose less of a health risk to people, but the copper can harm marine life if it's used for docks or pilings.

Beware, though, that the alternatives can be 10 percent to 30 percent more expensive than CCA, at least until demand increases. For now, you can special-order the wood from lumber and home improvement-stores.

Homeowners have to make their own decisions about what to do about the wood in their back yards, depending on how much risk they are willing to accept. Not sure if your deck is made of CCA? It probably is. It's been the most popular outdoor wood in the South for decades.

If you want to find out the exact levels of arsenic in your back yard, you can order tests from the Environmental Working Group at ( http://www.ewg.org ). They cost about $15, with a $5 shipping charge.

To help you make a decision about how to handle your CCA wood, we've waded through the scientific journals and government studies to come up with the best advice. But be aware - studies contradict each other, and a special EPA scientific advisory panel said more research is needed.

People with a big budget can replace the old wood with non-arsenic-treated wood, plastic decking or wood that's naturally rot-resistant, such as cypress or cedar.

If your child is playing on a pressure-treated playset, get rid of it. Environmentally aware consumers should take the old wood to a lined landfill. Florida allows the old wood to be dumped in unlined landfills, but state regulators are worried that the chemicals will contaminate groundwater.

If you're stuck with a CCA-treated deck, gazebo, picnic table or boardwalk, and don't have the cash to replace it, here's some advice:

CLEANING: Do not use bleach when you pressure-wash, and don't use commercial "deck brighteners" on the wood. These are fine for non-CCA decks. With CCA wood, bleach creates a very nasty form of chromium - hexavalent chromium - the same chemical made famous in the movie about a polluted town, Erin Brockovich. If you're pressure-washing with bleach, you're spreading hexavalent chromium - and arsenic - all over the place. Use water alone to clean your deck.

Don't buy deck brighteners that contain sodium percarbonate or sodium bisulfate to use on a CCA deck.

REPAIRING: Don't sand it, or you'll end up with sawdust that has enough toxic chemicals in it to rank as hazardous waste. The only reason it isn't officially on the government's hazardous waste list is because the industry got a special loophole in the 1980s.

PROTECTING: Seal it. Every year. This advice seems contrary to the whole purpose of the wood - which is supposed to be low-maintenance. But if you want to keep arsenic and chromium from leaking out, you have to put some type of barrier on decks and playsets. What kind of sealant? The jury is still out.

"There's no clear sealant that stands out above the others, but sealing is better than not sealing," said Tim Townsend, a University of Florida researcher who has been studying pollution from CCA wood.

The EPA's science panel says polyurethane sealants are a good bet. Many parks use a product called "Deck and Shake" ( http://www.deckandshake.com ). Other studies suggest using an oil-based stain. But few studies have looked at how the sealants hold in arsenic and chromium over a long period of time. That's why the experts say to seal it every year to be safe.

Painting the wood works, but then you have the problem of peeling later, which means sanding, which creates arsenic and chromium dust. Also, there's a concern that kids might eat paint chips coated with arsenic and chromium.

PICNIC TABLES: If you have an arsenic-treated picnic table, never put your food right on it and never cut things on it. (Like we've been doing for years.) Put a tablecloth over it, at least. Consider replacing an arsenic-treated picnic table altogether.

GARDENS: The soil near CCA posts has arsenic in it. The Times found that out last year, when it tested five playgrounds at random in the Tampa Bay area and found elevated arsenic in the dirt at every one. Some of the arsenic levels were higher than the state allows when it makes polluters clean up neighborhoods. Wood-treatment companies say Florida has a ridiculously low arsenic standards and that "elevated" levels here are the same as natural arsenic in soil elsewhere. Still, Florida does have a low level of arsenic in its soil, so it makes sense to keep it that way.

The next battle over CCA wood is going to be disposal, as homeowners throughout Florida tear out old decks. The state's solid-waste experts are sorting out the problem now. One concern is that "recycled" wood mulch is popping up all over Florida, and it's got arsenic and chromium in it from old CCA wood.

The issue is headed to the courtroom. Already, some individuals have won settlements with the wood-treatment industry after they were poisoned while working with the wood or getting splinters from it. Two national class-action lawsuits have been filed, alleging that the wood-treatment industry, Lowe's and Home Depot were negligent because they didn't tell consumers what was in the wood.

If you're concerned, tell your home-improvement store you want a less-toxic product for your home.

"The main problem is that people can't believe that anything this bad would be allowed out there," said Wiles, of the Environmental Working Group. "People think: No way - you must be nuts! No one would put a product on the marketplace that when you clean it, it makes hexavalent chromium. But they did."

QUESTIONS AND ANSWERS ABOUT ARSENIC - TREATED WOOD

Q: What does the voluntary ban on CCA wood mean?

A: The voluntary ban only covers wood that's likely to come into contact with people, such as decks, boardwalks and playgrounds. CCA wood will still be available for plywood, marine pilings, highway guardrails, bridges, structural timbers for houses, siding, shingles, utility poles, and some agricultural projects, including oyster farms.

Q: How can arsenic affect you?

A: Chronic exposure to arsenic can cause cancer or other health problems. You can pick up minute levels of arsenic from touching treated wood or from touching soil that is contaminated with arsenic.

But it doesn't readily absorb through the skin. The main route of exposure from CCA-treated wood is hand-to-mouth, meaning people touch the wood or contaminated dirt and then eat, smoke or put their hands in their mouths.

People also can inhale arsenic sawdust when working with the wood. Smoke from treated-wood fires is toxic, and the ash is hazardous.

Some people have won legal settlements with the wood-treatment industry after being poisoned by the wood. Arsenic poisoning can cause neurological problems, numbness and paralysis.

Q: How much risk does it pose?

A: That's a tricky question, as homeowners will soon find out if they call around for an answer.

Sometimes, researchers are being paid by the very industry that produces a toxin. Sometimes, government regulators don't have the resources to do their own risk analysis. And, almost always, everyone involved argues over how, exactly, the risk is calculated. Is it based on a full-grown adult? On a small child? Many times, authorities contradict one another, with one state going with one number, another state going with a different number, and the federal government going with another.

A toxicologist hired by the state Department of Environmental Protection says children can pick up enough arsenic during their childhood years playing on wooden playgrounds to increase their risk of cancer later in life.

The wood-treatment industry says arsenic comes off the wood, but says the levels are too low to worry about.

In the end, consumers have to make a judgment call on how much risk - or how many unknowns - they are willing to accept.

Q: How can I get my neighborhood playground tested?

A: Call your local government.

Do's and don'ts

Don't bleach or use deck brighteners on CCA wood.

Don't inhale the sawdust. Saw the wood outdoors. Wear a dust mask. Collect the sawdust and throw it away.

Don't use CCA wood for cutting boards or counter tops.

Don't use CCA wood to store food or animal feed.

Don't use CCA wood for wood chips or mulch.

Don't burn CCA wood; the smoke and ash are toxic.

Don't let CCA wood come into contact with drinking water.

Don't grow edible plants near CCA wood; put a plastic liner on the inside of CCA boards used to frame garden beds.

Wash exposed areas thoroughly after working with the wood - and before eating, drinking or smoking.

Wash children's hands after they play on CCA-wood playgrounds.

If sawdust gets on your clothes, wash them separately.

Keep children and pets out of under-deck areas.

Only use CCA wood that is visibly clean, dry and free of surface residue.

Don't store tools or children's toys under a CCA-treated deck.

Don't let kids or pets play beneath CCA-treated structures.

- Sources: U.S. Environmental Protection Agency, American Wood Preservers Institute, Connecticut Department of Health, Florida Departments of Health and Environmental Protection.