Tim Bower

Attention, all green shoppers. Before you buy that adorable bamboo-fiber panda T-shirt, hear this: although bamboo is a fast-growing plant that requires little space, water, or pesticide, turning those stalks into soft fabric can come with a hefty environmental cost. Most bamboo fiber is processed chemically using caustic soda, which is one of the major ingredients of Drano. It kills aquatic life when dumped into waterways and can burn the lungs and skin of factory workers who handle the stuff.

Bamboo can also be processed mechanically, the stalks crushed and broken down using enzymes -- a method far less harmful to the environment and factory workers. To find these garments, look for labels that refer to bamboo linen rather than bamboo rayon or just bamboo. In 2009 the Federal Trade Commission began cracking down on companies that label and market chemically processed bamboo as a natural, eco-friendly fiber, since the methods involved are the same as those used to produce rayon -- also derived from a "natural" substance (in this case, cellulose) and requiring heavy chemical processing. As a result, those bamboo textile companies must, by law, label and advertise their clothing as rayon, not bamboo.