Is It Okay to Build a Strawberry Bed Out of Railroad Ties?

Creosote

• Creosote occurs naturally in the resin of the creosote bush. It is also produced through high-pressure treatment of coal and lumber, such as beechwood. Coal-tar creosote is the kind primarily used in the United States as a preservative for materials, including wooden railroad ties. It is the dark, gooey material that oozes from new railroad ties and the base of telephone polls on hot days. Polycyclic aromatic hydrocarbons (PACs), such as naphthalene -- the chemical that gives mothballs their strong smell and insecticidal property -- are the main toxins in coal-tar creosote. The U.S. Environmental Protection Agency has identified PACs as being carcinogenic. In 2008, it prohibited the residential use of creosote.

Toxicity and Kids

• The U.S. Environmental Protection Agency administers numerous Superfund sites for remediation of creosote in soil and ground water at former manufacturing facilities nationwide. In a 2005 report about a Missouri facility not on the list, the U.S. Department of Health and Human Services found significant air and soil pollution of naphthalene and other PACs. It noted that children receive more exposure to air and soil contaminants than adults due to "frequent hand-to-mouth contact."

Strawberries and Creosote

• Strawberries are one of the fruits most popular with children and often appear in school lunchboxes. When playing near a bed of ripening strawberries, kids are often tempted to pluck and eat them. Creosote toxins in soil can be absorbed by strawberry roots. Children are vulnerable to absorbing the poisons through their skin and intestinal system when they touch soil in railroad-tie beds and consume fruit grown there.

Railroad-Tie Substitutes

• Although more expensive than railroad ties, rot-resistant lumbers such as cedar and redwood are healthier choices for constructing raised beds. Colorado State University notes that less expensive, copper-treated lumber is also safe for garden boxes containing edibles. Concrete blocks, bricks and rock are other solutions. The ultimate, inexpensive solution is to create a raised bed without walls. This requires mounding well-prepared soil and mulching it with grass, leaves or another organic material to minimize erosion, the university says.