What to do about arsenic?
By JULIE HAUSERMAN
© St. Petersburg Times, published March 16, 2001
Playgrounds made of treated wood in Tampa and Tarpon Springs are being closed temporarily out of concern that arsenic is leaching out of the wood and into the soil.
But what about your backyard play set? Most wooden play sets are made of the same material. So are picnic tables, decks, fences, boardwalks and gazebos. Virtually all the pressure-treated lumber you buy at home-improvement stores contains the same pesticide: chromium copper arsenate, or CCA.
The St. Petersburg Times reported Sunday that arsenic is leaking from CCA wood into soils all over Florida. The wood-treatment industry says -- and some independent toxicologists agree -- that the levels are low and don't pose a hazard to children or adults. They point out that arsenic is a naturally occurring element that's in soil, water and air and that Florida has one of the most stringent soil safety limits in the country.
The Times tested five playgrounds and found arsenic at levels higher than the state's safety standard in every case. That prompted a flood of calls from readers with questions. Here, we try to answer some of them:
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 any homeowner 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.
In the case of treated wood, the industry hired Dr. Christopher Teaf, a Florida State University toxicologist, to evaluate the risk of arsenic in soil under CCA-treated decks. Teaf concluded the risk of a child getting cancer is remote. Teaf prepared his report for Hopping Green Sams & Smith, the wood-treatment industry's Florida lobbyists. His conclusion: A child who was exposed to the soil under a pressure-treated deck two days a week for five years has little cancer risk. They face a greater risk from drinking a quart of water daily because even drinking water contains traces of arsenic.
Teaf also noted: "The concentrations of arsenic in soil under decks have been reported by several investigators with widely varying results. It appears that such factors as surface area of the deck, age of the deck, soil type, soil sampling profile, surface topography, and other site-specific characteristics are important in determining soil concentrations. These factors are not well understood and no systematic study has been conducted to our knowledge."
Florida Department of Health toxicologist Joe Sekerke also estimated a child's risk of getting cancer from the arsenic that the Times found in the playground soils as very low.
"There's very little risk of a child getting cancer from the playgrounds at the levels you found," Sekerke said. "If the levels are higher than that, or they eat a lot of dirt, it's more likely."
Sekerke hasn't done a study, just some quick calculations this week, based on the Times test results. At first, he told the Times a child would have to eat a quarter-pound of the playground soil every day of their lives to get cancer. Then he called back, and lowered his estimate, saying a child would have to eat a teaspoon or a teaspoon and a half of dirt every day for 30 years to get cancer.
Other private and government studies offer varied conclusions.
In the end, consumers have to make a judgment call on how much risk -- or how many unknowns -- they are willing to accept.
Q: If I'm concerned about arsenic in the soil, what should I do?
A: You can call a private laboratory and pay for tests of the soil and/or the wood.
Testing companies contacted Thursday say they charge up to $40 to test backyard soil for arsenic.
Thornton Laboratories in Tampa charges $36.50 per sample. Project manager Tina Fritz said homeowners should supply a half cup of soil in a zipper-lock bag. It takes about 10 days to get the results, she said.
KNL Laboratory Services of Tampa charges $40 as well. KNL's Mary Anderson said people should bring in a 4-ounce sample. It takes about 10 days.
Severn Trent Laboratories of Tampa generally charges $40 per sample, said Andre Rachmaninoff of that laboratory.
Q: How can I get my neighborhood playground tested?
A: Call your local government.
Q: Is there some alternative to CCA-wood?
A: Yes. One alternative is ACQ, which is pressure-treated, has a long outdoor life and doesn't contain arsenic. Some lumber companies can special-order it. Home improvement stores might start to carry it if demand increases.
Because it isn't yet widely available, it costs more. Ask for price quotes. Gov. Jeb Bush announced this week that he wants the state's own wood-treatment plant, which makes highway guard rails, park boardwalks and other outdoor wood for state agencies, to switch to arsenic-free treatment.
Plastic decking is another option.
Q: If I decide to remove my pressure-treated wood, where do I take it?
A: Pressure-treated lumber has enough arsenic in it to be classified as a hazardous waste, but the industry got an exemption from hazardous-waste laws years ago. State law allows you to take it to a lined landfill, or an unlined construction debris landfill. Be aware, though, that state officials are concerned about arsenic they say is leaking out of the unlined landfills. They may soon require pressure-treated lumber go only to lined landfills. The worst disposal option would be to take it to a wood recycler who makes mulch.
Q: What about recycled wood mulch?
A: Pressure-treated lumber is not supposed to be shredded into mulch. In reality, though, it's hard for recyclers to tell the difference between old CCA-wood and non-treated wood. When Florida researchers did random tests of recycled wood mulch, they found arsenic.
Dos and don'ts
Don't inhale sawdust from treated wood. Saw the wood outdoors. Wear a dust mask.
Don't use treated wood for cutting boards or counter tops.
Don't use treated wood to store food or animal feed.
Don't use treated wood for wood chips or mulch.
Don't burn treated wood; the smoke and ash are toxic.
Don't let treated wood come into contact with drinking water.
Don't grow edible plants near treated decks; 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 treated-wood playgrounds.
If sawdust gets on your clothes, wash them separately from other laundry.
Keep children and pets out of under-deck areas.
Only use treated wood that is visibly clean, dry and free of surface residue.
Some experts recommend that treated wood be coated with a sealant every two years, but how much that helps is debatable. A Consumer Product Safety Commission study found that sealants didn't keep the arsenic from leaching out. Sealants might be a good idea, though, to prevent splinters.
Add an extra layer of ground cover -- but not recycled wood mulch -- under your play set to keep kids from having contact with the soil.
- Sources: U.S. Environmental Protection Agency, American Wood Preservers Institute, Connecticut Department of Health, Florida Departments of Health and Environmental Protection.
Some Florida wood suppliers can provide treated wood that doesn't contain arsenic. The wood isn't carried in stores, but it can be special-ordered. Ask for "ACQ."
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Decks and Docks Lumber Co.
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Deerfield Builders Supply
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West Orange Lumber Co.
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