March 18, 2008 - Researchers have found a known carcinogen in personal care products made by high-profile green brands, including Seventh Generation and Nature's Gate, L.A. Times reports. Tests of more than 100 "natural" or "organic" soaps, shampoos, and other products found that nearly half contain a cancer-causing byproduct that is created when petrochemicals are used during manufacture.

The study, sponsored by the Organic Consumers Association (OCA), found the chemical byproduct 1,4-dioxane in 47 of 100 products tested. The U.S. EPA considers 1,4-dioxane a "probably human carcinogen," although safe levels of exposure in humans have yet to be determined.

Traditional shampoos and soaps typically contain small amounts of 1,4 dioxane, but brands in the LOHAS (Lifestyles of Health and Sustainability) market must meet significantly higher consumer expectations for environmental and safety performance. By necessity, companies have been quick to answer the OCA controversy; Seventh Generation, for example, posted this response to the study on its website:

"Consistent with our core mission, we have worked with surfactant manufacturers for many years to reduce levels of 1,4-dixoane in ethoxylated surfactants and it is our intent to completely eliminate 1,4-dioxane from all of our products."

Seventh Generation's Martin Wolf, director of product and environmental technology, told the L.A. Times, "The natural world is filled with things that can harm...All we can do is work as hard as we can to keep the levels as low as possible and keep our products as safe as possible."

According to one chemical expert, however, 1,4 dioxane can be avoided  - with some tradeoffs. "It typically requires a higher price point and sometimes performance restrictions for the product," says Josef Koester of Cognis Corp., a chemical company that specializes in "green" formulations.

OCA is advocating standards for chemical components allowed in products that are sold as "natural" or "organic."