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I’ve got something important to talk to you about. Do you have raised garden beds for your vegetables? What kind of wood are they made of? Don’t know? Let me help you figure it out, because your health may depend on it.

If the wood has little marks in a measured pattern all along the surface, you’ve got pressure-treated wood — once the gold standard for wood used in contact with soil. Not so anymore.

Michael Heumann, an epidemiologist with the Oregon Department of Human Services, sends out this warning: “Our advice is: Get rid of it, today. The problem with treated wood is that it contains arsenic, and arsenic is known to cause cancer.”

Ninety percent of the arsenic used in this country is applied to the production of pressure-treated or so-called CCA, for chromated copper arsenate, wood.

No surprise there. That’s why we bought it: The chemical stops termites and prevents rot. But health experts now think that by growing food in beds made with this wood, we’re eating the chemicals.

Heumann also recommends that gardeners remove and replace the soil that was in contact with the wood. He cites a study by the University of Connecticut Department of Analytical Chemistry that found that lettuce and tomato roots grown in raised beds built with CCA wood contained 10 times more arsenic than vegetables grown near untreated wood.

The Environmental Protection Agency agrees that over time, arsenic leaches from CCA-treated wood products. The agency will ban its use by 2004.

The wood is still for sale — you can find red warning labels on the ends of CCA lumber at most of the big-box stores. The wood products industry stands behind CCA’s safety but voluntarily agreed to phase it out of production.

“You’ve got a product that’s been in service for over 80 years that really has a very good track record,” says Dennis McWhirter of Exterior Wood Inc., based in Washougal, Wash. “Scientifically, there’s really no data to back up any dangers. It’s mostly emotionally based.”

As a backup, the industry is making some great alternatives. McWhirter’s company is the leading maker of wood treated with copper, boron and azole (CBA). It looks just like the old stuff, but is made with copper (to fight termites and decay) and boron (found in eyewash and mouthwash) instead of arsenic. Hillsboro-based Parr Lumber Co. was the first Oregon company to stop using CCA wood and replace it with CBA wood.

Mike Jansen of Parr Lumber called a poison control office to ask for health advice after building his own raised vegetable bed with the arsenic-laced wood years ago.

“They said wrap it with 6-mil black poly plastic and keep your plants 6 inches from the edge. That should have told me something.” Jansen says.

Parr Lumber made the switch to CBA wood in June because “you’re dealing primarily with a biodegradable product. … This stuff is found in a lot of products that are right in your kitchen.”

There’s also recycled lumber called Trex made with resin, plastic bags and shrink-wrap. Both CBA and Trex products cost a little more than the old stuff, but Jansen looks at it this way: “You’re talking about $1.68 more for a 2-by-12 of CBA. But for the people who are concerned about their health or children, that’s a small price to pay.”

What should you do while the experts disagree about the health risks? I’m not a chemist, but I can give you some advice: Listen to experts who have the background and understand chemistry but don’t have any money at stake.