For decades, cooks in homes and restaurants have been urged to use plastic, rather than wood cutting boards in the name of food safety. The fear is that disease-causing bacteria (i.e. Salmonnella from raw chicken) will soak into a cutting board and later contaminate other foods cut on the same surface then served uncooked.
It's become an article of faith among "experts" that plastic cutting boards are safer than wood for food preparation because plastic is less hospitable to bacteria. It seems reasonable, but is not factual, according to U. of Wisconsin's Food Research Institute.
Food microbiologists, Dean Cliver and Nese Ak, at the Institute had an objective to learn about bacterial contamination of wood cutting boards and to find a way to decontaminate the wood so that it would be almost as safe as plastic. But that's not what happened -- instead, they found that, in some as yet unknown way, wooden cutting boards kill bacteria that normally survive on plastic boards.
The scientists purposely contaminated seven species of wood cutting boards and four types of plastic boards with Salmonella, Listeria, and E. coli (all known to produce food poisoning). The contaminated boards were incubated overnight at refrigerator and room temperatures and at high and typical humidity levels. They found that 99.9% of the bacteria on the wood boards had died after three minutes, yet none of the bacteria had died on the plastic. Overnight, the bacteria on the plastic flourished, but no bacterial samples could be recovered from the wooden boards treated exactly the same way.
A literature search by the scientists could not find any studies which concluded that wood cutting boards were unsafe, and have no idea as to how the rumor started, nor have they been successful in recovering a compound in the wood that inhibits the bacteria.