Personal-care products such as toothpastes and shampoos that are labeled "natural" often have two lists of ingredients: those they contain, and those they don't. That second list is important to people who want to know as much about what's staying out of their bodies as about what's going in. But ingredients on those "contains no" lists may not cause harm; they may simply be victims of Web-fueled health scares.

Makers of such plant-based product lines as Kiss My Face, Burt's Bees and Jason Natural Products know their buyers are particularly attentive to such scares -- regardless of scientific merit. Rather than risk losing customers, some will drop besmirched ingredients, even if they're thought safe.

"We really do have to take it into consideration what our consumers will think. We have to be a bit more cautious," said Angela Green, associate brand manager for Jason Natural Products.

Here are some ingredients that appear on "contains no" lists even though many researchers consider them safe:

Sodium laurel sulfate The American Cancer Society and other health organizations say there's no science to support the claim on some Web sites that this foaming agent in toothpastes and shampoos causes cancer. At worst, health officials say, it can be a minor skin irritant.

Propylene glycol This skin softener and cosmetic ingredient may be a chemical relative of antifreeze, but the Food and Drug Administration puts it on the agency's "generally recognized as safe" list for food. The Cosmetic Ingredient Review, an industry-funded board, classifies it as safe in cosmetics at concentrations up to 50 percent.

Parabens A few years ago, studies in the Journal of Applied Toxicology and the European Journal of Cancer Prevention tied these preservatives in deodorants and antiperspirants to breast cancer. Independent scientists have since dismissed those studies as flawed. The National Cancer Institute says there is no conclusive evidence linking the chemicals to disease.

Two reputable sources for checking out dubious-sounding warnings are the "Health Related Hoaxes and Rumors" page maintained by the Centers for Disease Control and Prevention (www.cdc.gov/doc.do/id/0900f3ec80226b9c) and "I Heard It On The Internet," sponsored by the National Research Center for Women & Families (www.center4research.org/internet.html).

-- Jason Feifer

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