Programs that "offset your carbon footprint." Bamboo flooring that's "eco-friendly." Products that are shipped in "sustainable packaging." These are just a few of the countless green claims you've likely seen in recent years, but are they legit? Some are, some aren't.

The Federal Trade Commission, which first issued its Guides for the Use of Environmental Marketing Claims, or Green Guides, in 1992 and updated them most recently in 1998, is deciding whether to update them again in light of the proliferation of new products with green claims.

In early 2008, the FTC held three public workshops that covered carbon offsets and renewable-energy certificates, green-packaging claims, and green building and textiles as part of its efforts to examine marketplace developments and consumer perceptions of environmental claims. Consumers Union, the nonprofit publisher of the Home & Garden blog and Consumer Reports, participated in two sessions and contributed comments on steps the FTC should take to reduce marketplace deception related to carbon offsets and presented reasons why bamboo textiles might not be as eco-friendly as marketers tout. (Download a PDF of CU's comments.)

The Green Guides themselves are not enforceable by law, but they do have some teeth: If a marketer makes claims that are inconsistent with the guides, the FTC can take legal action under Section 5 of the FTC Act, which prohibits unfair or deceptive practices. Companies face an $11,000 fine per violation.—Kristi Wiedemann

Essential information: Until the Green Guides have been updated, you can check out the FTC's "Sorting Out 'Green' Advertising Claims" and "Eco-Speak: A User's Guide to the Language of Recycling."