The "sin of no proof" was another common transgression at the show, with few companies able to provide proof of their environmental claims, Case says. A foam insulation product was guilty of the "sin of irrelevance," an environmental claim that may be truthful but is unimportant and unhelpful for consumers. "They advertised that it did not use CFCs," Case says. "CFCs were banned in 1978. It is illegal to use CFCs. But many consumers don't know that," so they might be misled when they don't see other companies making the same claim.

The "sin of vagueness" identifies those terms such as "chemical-free" and "non-toxic" whose meaning is poorly defined and likely to be misunderstood. Nothing is free of chemicals, Case says, and everything is toxic in sufficient quantities. The "sin of lesser of two evils" applies to claims such as "organic" cigarettes, that may be true but might distract consumers from the environmental impacts of the category, while the "sin of fibbing," the least common sin, applies to claims that are simply false, such as a caulking product that claims to be Energy Star-registered, but does not show up on the official Energy Star Web site.

Risky Business

Marketing experts and green advocates see dangers in such greenwashing claims, not the least of which is the risk of consumer cynicism. Architect and green building expert Peter Pfeiffer remembers the first green movement, when early versions of products such as solar collectors and tankless water heaters were held up as environmentally sensitive but didn't perform. "When you rely on these products and they break, generally speaking people get down on the whole movement," says the founding principal of Barley and Pfeiffer Architects in Austin, Texas.

Market research firm Leo J. Shapiro & Associates validates the concern. In a study titled "What Is 'Green' and Why It Matters," the firm found that consumers were concerned about companies riding the "environmentalist bandwagon" for their own financial gain, and noted that the skepticism might be a reflection of past experiences with green products. "Companies are rushing to put green products out there," says Arturo Angel, the firm's research director. "There's a risk to the brand."

While consumers will choose green products if they deliver the same benefits and features for the same price as non-green versions, "they're absolutely not willing to compromise on performance to get green products," he says.

Green fatigue is also a risk as consumers become confused by sometimes misleading environmental claims, says Lloyd Alter, an Ontario architect who now writes full-time on sustainability and other issues for Treehugger.com and Planetgreen.com. "People don't know what to do, so they just don't do it," he says.

Alter points to one countertop company that was extolling the 12 percent recycled content of its products. "The recycled material is their own scrap from mistakes," Alter laments. "They're building an entire ad campaign around it." He contrasts that type of exploitation with competitor IceStone's marketing campaign, which allows customers to follow every step in the life cycle of its sustainable countertops on its Web page.

Meanwhile, decisions could be confusing for the consumer, he says. "They'll say, 'I don't know which is better, so let's just use granite.'"