Bamboo has great environmental street cred. Lately, though, I have read questions about how sustainable it really is.

On the upside, no other raw material is as versatile as bamboo. It can make a wider variety of products than any other substance. These include almost anything that can be made of wood and much that can be made of plastic. In hard products, it’s stronger than steel.

Bamboo also makes a very soft fabric. You can eat it, too. Bamboo shoots are a staple ingredient in Chinese cooking.

Harvesting it does not kill the plant. It grows so fast it’s ready for harvest again in about three years. Since it grows like a weed, it doesn’t need fertilizer or pesticides. It needs a warm climate but doesn’t care how dry or wet it is.

But here are some of the downsides: Demand for bamboo tempts some growers to use unsustainable practices. Making bamboo rayon uses toxic chemicals. Research has questioned the safety of using reusable bamboo coffee cups. How serious are these questions?

Thoughts on the market for bamboo

Bamboo grows on every continent but Europe and Antarctica. China, though, accounts for 65% of bamboo exports. It must, therefore, harvest enough to dominate exports on top of what it needs for itself.

The Chinese have used bamboo for millennia. Demand began to surge after a ban on logging in 1998. The ban severely limited how much Chinese timber was available. But it applied only to wood, not bamboo.

According to a report published in 2011 by the Pulitzer Center in China, one small bamboo factory in southern Sichuan processed nearly 20 tons every year. In peak season, it couldn’t up with demand. China has many more factories. Lots of them are bigger.

Consider only one product, disposable chopsticks. Every year, China goes through 57 billion pairs. Growing enough bamboo requires 445 acres. Think of how much land is needed for all the other bamboo products! Bamboo harvesting grew from 260 million tons in 1990 to 1.2 billion tons in  2005.

I haven’t found more recent statistics. Demand dropped in the worldwide recession of 2008. It seems reasonable that Chinese bamboo harvests have grown past pre-recession levels.

The environmental impact of Chinese bamboo production

The Chinese government encouraged farmers to plant more bamboo. In response, unfortunately, they overharvested natural forests. They also planted monoculture plantations.

Monoculture means using land for a single crop. Most modern farms all over the world use that model.  It wreaks havoc for several reasons.

For one thing, depletes the soil of the nutrients that one crop needs.  For another, it concentrates that crop’s pests, but not their natural predators.

Therefore, monocultures deplete biodiversity. They also need more fertilizer and pesticides than other farming methods. Monoculture bamboo plantations degrade the function of the entire ecosystem.

Returning bamboo forests to a natural condition would be good for the environment. Not only that, it would have good economic effects. Unfortunately, farmers think they can make more money from monocultures. As long as that’s the case the future for the health of bamboo forests all over China remains uncertain.

The trouble with bamboo fabric

Bamboo can be made into two kinds of fabric: linen and rayon. Making bamboo linen uses the same ancient processes as any other linen. It is not a soft fabric. The most common and popular bamboo fabric is the silky soft rayon.

Rayon requires treatment of natural fibers with chemicals to regenerate it as cellulose fiber. So it’s neither a natural fiber nor a synthetic one.  It comes in three varieties: viscose, modal, and lyocell. Each uses different chemicals and processes. Makers of lyocell, bamboo or not, claim a more eco-friendly process.

Most bamboo fabric is viscose. Making it requires sulfuric acid and other toxic chemicals. Environmentalists wonder, do factories work hard enough to protect workers from these chemicals and dispose of them properly?

More and more products are made using a closed-loop process. That means, among other things, that they reclaim and reuse solvents and other chemicals. Many environmentalists, however, view such claims with suspicion.

Frankly, I think people who stop buying bamboo fabric when they find out about the chemicals are off base. Nearly every fabric raises environmental concerns. Nothing is entirely green. Bamboo still seems the most sustainable choice.

• Growing cotton requires lots of water. It also uses more fertilizer and pesticides than any other crop. They harm workers’ health and pollute water. Organic cotton uses natural pesticides, which are not really any safer.
• Most rayon comes from wood. In any comparison of wood with bamboo, bamboo comes out more sustainable. In either case, making it uses the same chemicals.
• Polyester starts out as oil. It is a kind of plastic. All fabrics shed microparticles when washed. Most, including rayon, biodegrade. Polyester doesn’t. No wastewater treatment can filter out plastic microparticles. They go directly to the oceans.

The trouble with bamboo coffee cups

Are reusable bamboo coffee cups greener than disposable cups? It would seem so. Unfortunately, a German study found otherwise.

Stiftung Warrentest tested twelve different cups and found dangerous chemicals in all of them. It also faulted the manufacturers for making false advertising claims.

Advertisers claim that the cups are made from bamboo fiber. They fail to mention what else is in them.  The fibers are ground to a powder, mixed with glue made from melamine resin, and formed into a cup. Melamine resin is made from melamine and formaldehyde. Both ingredients carry health risks.

Actually, melamine used to be a common material for making table service in the 1950s and ’60s. It lost popularity because it stains and scratches. Warrentest notes that melamine resin is safe to use under certain conditions. For one thing, products that contain it must be kept below 158ºF.

Coffee exposes it to higher temperatures than that. The experiment filled cups with an acidic, coffee-like liquid and kept it at a temperature of 158º for two hours. Then it analyzed the liquid.

Seven of the cups released a very high amount of melamine. Some also released high amounts of formaldehyde. Only one brand, Chicmic, released only little harmful chemicals. Microwaving the cups damages them and also releases harmful chemicals.

Despite advertising claims, the cups are not recyclable or biodegradable. Bamboo is biodegradable, but melamine resin is not. Neither is melamine resin recyclable.

Bottom line: prefer reusable coffee cups. If you must use a refillable cup, prefer something other than bamboo.

Otherwise, bamboo products remain the greenest you can find.

Sources:

China’s appetite for bamboo is damaging forests / Sean Gallagher, The Pulitzer Center in China. August 12, 2011
How sustainable is bamboo and is it really all that eco-friendly? / Kate Hall, The Green Hub. October 2019
‘Keep your hands off’ bamboo coffee cups, German consumer group warns / DW.com [July 23, 2019]

Photo credits:
Bamboo plant. Some rights reserved by makenzie and john. [Link to Flickr no longer works.]
Bamboo cutting board. Some rights reserved by Matthew Oliphant
Sagano Bamboo Forest. Some rights reserved by Steve Cadman
Bamboo clothing. Some rights reserved by Zeyus Media
Bamboo reusable coffee cup. found on Pinterest