Decks, Fences & Arsenic

It's a good thing that pressure-treated lumber for residential use was phased out in 2003.  A new scientific study concludes that arsenic from lumber treated with chromated copper arsenate (CCA) will continue to leach into soil and landfills for decades to come.  That's one reason I've been advising clients in years past to switch to cedar (as in the deck, left) or other woods for decks, fences, and other garden structures.

Researchers at the University of Miami, the University of Florida and Florida International University studied leaching of arsenic from actual decks into the soil and into a simulated landfill.  Their results, published in the current online issue of Environmental Science & Technology, showed that arsenic levels were 100 times greater in water runoff from a deck constructed of CCA-treated lumber. Helena Solo-Gabriele, a professor of environmental engineering at the University of Miami, said only small fractions of arsenic leach out in a given year, but that the impact over time can be quite significant.