Do synthetic backings on natural carpeting defeat the purpose? Q. I have been looking into wool carpeting because wool is a natural fiber that does not emit chemicals. But I am learning that most wool carpets have plastics and other synthetics in the backings, and they also are treated with moth proofing agents, which many experts have told me is unnecessary. Does this negate the indoor-air friendly and planet-friendly aspects of natural wool carpeting? A. All discussions about “green” products involve levels or degrees of greenness. That said, the answer to your question is yes – to some extent. Because it is not made from petrochemicals, the wool fiber in the carpet will be far more indoor-air friendly than traditional synthetic fibers, despite the use of synthetic backings like polypropylene. Keep in mind that there are products like Nature’s Carpet “Dark Green” line that offer New Zealand and British Wool carpets with no chemical treatments and natural jute backings. Not only does this eliminate any concern you have about chemical emissions, but leads into the second point you’ve raised about planet-friendly aspects.