This page describes arsenic risks from pressure-treated wood structures such as decks, playscapes, sheds and treehouses that you may have in your yard. Pressure-treated wood is rot resistant because it contains aresnic based pesticides that have been injected into the wood under high pressure. Most pressure-treated wood sold before January 2005 contained this toxic substance. After that date, the arsenic was replaced by safer antimicrobial agents.

IF you have a pre-2005 pressure-treated wood deck or other structure in your yard, it is likely a source of arsenic exposure - especially for young children.

ARSENIC TOXICITY - this metal is a carcinogen and nerve  toxicant that gained fame as a poisoning agent during the middle ages. The main concern for low level backyard exposures in children is an accumulated cance risk. Arsenic from the wood forms a dust residue on the surface which children can easily get on their hands. Their frequent mouth to hand activity brings it into their body. The soil under the structure will also be contaminated.
(See more information on Arsenic Toxicity)

WHAT YOU CAN DO

1) Coat pressure-treated wood structures every year in the spring with a sealant. It appears that oil-based deck stains work as well as any in keeping the arsenic in check.

2) Do not sand, power wash, or cut pre-2005 pressure-treated wood in your yard. This may release arsenic and spread it around your yard.

3) Assume the soil under the deck or playscape is contaminated too. So not let children or pets get into this area. For playscapes, cover the contaminated soil with a layer of sand or wood mulch/chips to prevent contact with aresenic in soil.

4) Consider replacing an aging deck or playscape with one using modern wood products. They will be free from arsenic. Bring the old pressure-treated wood boards to your town's landfill. Do not burn them yourself.

(More information and safety tips for arsenic-based pressure-treated wood from USEAP)


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