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Bamboo Boom: Is This Material for You?

It's not just for tiki torches anymore, but does this wood substitute really make for greener floors, clothing and other products?

Opportunity has a dark side, however: in the past, the increased demand tempted growers to clear natural forests and replace them with bamboo—a practice Ruiz-Pérez calls “completely crazy” from an environmental standpoint, because it erodes biodiversity and reduces the carbon capture benefits. But since the Chinese government reformed its forestry policy in the late 1990s, forest clearing for bamboo has been less common, according to Ruiz-Pérez, who has studied bamboo cultivation patterns using satellite imagery. “I’m not saying it doesn’t happen, but we haven’t seen it recently. On the contrary, we see bamboo grown on steep slopes and abandoned agricultural lands”—where, he explains, cultivation is likely a net benefit to the environment.

Farms range from very well managed to poorly managed, so far-reaching green claims are difficult to make. Water and pesticide use seem to be low, Ruiz-Pérez says, but demand can encourage farmers to pump up their use of synthetic fertilizers. Although statistics on fertilizer use in bamboo plantations are scarce, its use in Chinese agriculture in general has exploded in recent decades, leading to a host of environmental problems, including air, soil and groundwater pollution. One bamboo-producing county now offers financial incentives to growers willing to cut back on fertilizer and protect biodiversity, but such efforts are in their early stages.

Made in China
Even bamboo boosters acknowledge that the next steps in the process—those required to transform plants into flooring, fabric or other products—have environmental pitfalls. The glues that bind the strips into planks can contain formaldehyde, posing health risks to workers and possibly to consumers. Dyes can contain heavy metals.

Many consumers also do not realize that almost all the smooth, soft “bamboo” towels, T-shirts, socks and other textiles available in the U.S. are produced through a chemical process akin to the one used to make rayon. (In fact, the U.S. Federal Trade Commission requires most bamboo-based textiles to be labeled as rayon.) The specific details of the fabric production are the subject of much debate, but in general, making rayon includes “cooking” plant materials in lye and treating them with carbon disulfide—chronic exposure to which can cause nervous system damage. The multistep process creates a viscous solution that is extruded through nozzles into an acidic bath, where it hardens into fibers.

Processing is “certainly the major nongreen factor in bamboo fabric,” says Morris Saintsing, a founder and partner of the Andrews, S.C.–based company Bamboosa, which buys bamboo fiber and yarn made in China for its U.S.-manufactured clothing. Bamboosa, like many other U.S. bamboo clothing companies, is a customer of Hebei Jigao Chemical Fiber Company in northeastern China, which advertises its product as a “natural and environment-friendly fiber.” But exactly how much water and energy the company consumes in processing, along with where and how chemicals are used and discarded, is difficult to verify. Such information is “well guarded,” says Dawn Pickering, vice president of Pickering International, a San Francisco importer that is also a Hebei Jigao customer. (Hebei Jigao representatives did not respond to requests for comment.)

Hebei Jigao’s environmental management system is certified by the International Organization for Standardization, meaning only that a system for identifying environmental impacts is in place and that the company is committed to improvements—not that it has attained any particular level of performance.

Clean rayon production is possible: Austrian company Lenzing, which makes a type of rayon fabric from wood pulp, uses a “closed loop” process that recycles essentially all the required chemicals. Pickering, who visited Hebei Jigao in 2008, says the factory does have a sophisticated wastewater treatment system, but a closed-loop process would require an entirely new facility—an enormous investment that she says Chinese companies are not yet willing or able to make.

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