Bamboo products and sustainability: how eco-friendly are they?
How sustainable are bamboo products? At first appearances, bamboo is one of the most sustainable materials on earth. Let’s consider some of the ways.
First, it grows very rapidly from a rhizome, sort of an underground stem. That means that harvesting it doesn’t kill the plant. The rhizome remains in the ground, and another culm rises in place of the harvested one. Because it grows so fast, the new one is ready for harvest much faster than a new tree is. And because the rhizome remains, the plant continues to hold the soil in place.
Second, like any plant, it exchanges carbon dioxide for oxygen. But it does so faster than any other plant and releases more than 30% more oxygen into the air than a comparable mass of trees.
Third, it grows like a weed While it requires a warm client, it grows well in very moist or very dry soil. That can be a disadvantage if you’re trying to keep it out of your yard once it gets established. But it also means that a natural bamboo forest needs no fertilizer, pesticides, or irrigation.
But this third point starts to bring up some of the downsides. Nothing’s perfect in this world.
The economics of bamboo production and transportation
Although bamboo grows on every continent except Antarctica and Europe, most of it comes from China. Among all the nations of the world China is both the top producer, the top exporter, and the top consumer of bamboo.
In 1998, the Chinese government became alarmed about deforestation, so it banned logging. That, of course, severely limited the amount of wood available to Chinese manufacturers. Of course, the Chinese had used bamboo extensively for millennia. Because of bamboo’s great versatility, it can substitute for all of wood’s uses.
The logging ban, therefore, greatly increased the demand for bamboo. China harvested 260 million tons of bamboo in 1990. By 2005, production had risen to 1.2 billion tons.
And unfortunately, the Chinese culture has become every bit as addicted to convenience and disposable products as the US. So China uses 57 billion pairs of disposable bamboo chopsticks every year. It requires 445 acres to grow enough bamboo for that one product.
Since the majority of the world’s bamboo comes from China, we also need to consider the cost of transporting it. Just think of how far it must travel between where it’s harvested and the factories that make new products from it. As with any agricultural product, the means of transportation vary. It might travel part of that distance by rail, highway, sea, or air. Each of these choices has a different environmental impact.
How monoculture agriculture affects bamboo sustainability
With logging banned, the Chinese government urged farmers to plant enough bamboo to replace it. But Chinese law lacks adequate agricultural controls. Farmers first overharvested natural bamboo forests. Then they planted monoculture bamboo plantations.
Most modern farms worldwide grow monocultures. That is, each field or other plot of land grows only a single crop. All corn here, all wheat there, all avocados somewhere else, and so on.
Monocultures soon deplete the soil.
In a more natural area, one species of plant will supply some of the nutrients other species need. And with nothing that doesn’t belong, nothing is a weed. A variety of plant species also attracts a variety of soil microorganisms.
In a monoculture, the one crop uses up everything it needs, and nothing else replaces it naturally. So monocultures depend on fertilizers. Natural fertilizers, such as composted manure, would work adequately, but synthetic, petrochemical fertilizers dominate today’s agriculture.
What’s more, if everything in a field, forest, or orchard must be a single species, everything else becomes a weed. In fact, monocultures concentrate the pests that feed on that one species and eliminate their natural predators. So farmers must use pesticides to get rid of them. And so it goes. All of these chemicals accumulate in the soil and eventually pollute groundwater.
When ground is cleared to make a monoculture, it displaces all the wildlife that used to live there. It may even make life more difficult for some already vulnerable species. Therefore, monocultures reduce biodiversity in multiple ways.
Bamboo monocultures, therefore, undo some of the environmental advantages of natural bamboo forests. For farmers, monocultures have advantages of simplicity and efficiency. For example, growing only one crop on a large area means only one method of harvesting.
How sustainable are various bamboo products?
Wood and paper
In general, bamboo is a more sustainable alternative to similar products made from wood. Most tree plantations are monocultures, and all the trees on any one plot of land are about the same age. Harvesting trees kills them, of course. In place of a stand of mature trees, farmers plant seedlings and nurture them until they become suitable for harvesting.
Wood’s only environmental advantage over bamboo is the likelihood that it doesn’t travel as far from harvest to manufacturing plant.
Bamboo has great tensile strength. It can even substitute for steel in some applications, including reinforcing concrete. Bamboo flooring and bamboo furniture compare favorably to wood for sustainability. Bamboo paper and cardboard likewise require nothing more than the same processes and chemicals than making it from wood. Bamboo sustainability wins there, too.
Still, some less trendy alternatives may be even more sustainable. Take bamboo toilet paper, for example.
Who Gives a Crap sells bamboo toilet paper from its facilities in Australia. The bamboo itself, of course, comes from China. In fact, it is made into toilet paper there. The company claims there would be no environmental advantage to manufacturing the toilet paper in Australia. It’s certainly more eco-friendly than making it from virgin softwood.
Shipping and selling it within Australia should at least not raise any environmental eyebrows. But Australia is a long way from anywhere else. Who Gives a Crap exports its toilet paper all over the world. Transportation costs take away much of luster of bamboo sustainability.
Any manufacturer of bamboo toilet paper anywhere else in the world would incur even greater transportation costs. The distance between China and Australia is less than that between China and nearly any other major manufacturing country in the world.
Looking strictly at environmental impact, recycled toilet paper gets the edge over bamboo.
Bamboo fabric
I have written specifically about bamboo fabric on Sustainability Scout. Bamboo becomes linen by the same ancient processes used to make linen from flax. But when people think of bamboo as a super-soft fabric, they’re thinking of bamboo rayon.
Rayon originated in the 1880s, when it was made from wood. Whether wood or bamboo, fiber goes through very harsh chemical treatment to become rayon. So rayon isn’t quite a synthetic fabric, but it’s no longer a natural fabric. Nothing remains of the original fiber.
Thanks to all the toxic chemicals required to make it, bamboo fabric doesn’t have quite the environmental advantages of bamboo wood or paper. Many environmentalists don’t consider it sustainable at all.
But there is no point in comparing bamboo sheets with a bamboo headboard or bamboo floors. We have to compare bamboo rayon with other fabrics. Nothing is clearly any more eco-friendly. Therefore, bamboo sustainability looks pretty good for fabric, too.
· Synthetic fabrics such as polyester or nylon come from petroleum and require an array of chemicals to turn the oil into fabric. And then they shed microplastics.
· Other rayon comes from trees. In that case, bamboo rayon has the same advantages as bamboo wood or paper.
· Where bamboo requires no irrigation, cotton uses more water than most crops. Conventional cotton growing also requires fertilizers, pesticides, and exfoliants. Organic cotton requires more land and labor to produce the same amount of product. Making cotton fabric uses many of the same chemicals used for bamboo rayon.
· Silk may be the most sustainable alternative to bamboo rayon. The trees where the silkworms live grow on land that’s not useful for any other crop. It would be impossible to apply pesticides to them without killing the silkworms. But controlling temperature and humidity to raise silkworms requires a lot of energy. And some environmentalists have a hissy fit because making silk kills the silkworms.
Molded bamboo
I have also written about molded bamboo. Bamboo sustainability here looks pretty good, but not perfect.
What’s on the market today is a bamboo-plastic composite. It’s a subset of the century-old technology of plastic composites. That is, some kind of fiber serves as a filler, surrounded by a matrix of some kind of plastic resin. Bakelite, the first plastic composite, used wood or asbestos fiber.
Bamboo plastic composites are about 40% bamboo powder and 60% plastic matrix. Therefore, molded bamboo uses only about 60% of the petroleum of pure polymers.
The bamboo powder is a waste product that comes from manufacturing other bamboo items. Therefore, molded bamboo represents a kind of recycling.
It’s lighter than any plastic, so it takes less energy to transport molded bamboo products.
Those are environmental advantages over plastic. The downside, however, is that bamboo plastic resin is not recyclable. It’s also not biodegradable unless it uses a bioplastic matrix. But then it takes industrial composting to get it to degrade in reasonable time.
Also, molded bamboo doesn’t make good kitchenware. Both heat and acidic foods could make it release harmful chemicals and cause health problems.
Research is underway to find a way to make bamboo powder moldable without using a plastic matrix. When it succeeds and becomes available commercially, molded bamboo will have even greater advantages over plastic than the current bamboo-plastic composites. For one thing, it will be fully biodegradable.
Bamboo coffee cups
One would think that reusable bamboo coffee cups would be more sustainable than disposable paper cups. But not according to a German study of bamboo coffee cups from twelve different manufacturers.
The cups are made from bamboo-plastic composite, with a resin of melamine and formaldehyde.
In the 1950s, melamine resin was a popular material for making table service. Unfortunately, it stains and scratches easily. The public soon turned away from it.
But there’s a bigger problem for coffee cups. Melamine is safe to use provided that whatever is put in it doesn’t exceed 158º F. Coffee is hotter than that. The study filled all of the cups with an acidic liquid similar to coffee and kept it at 158º F for two hours.
All but one of the cups released high levels of melamine and/or formaldehyde into the liquid. Microwaving the cups also damaged them and caused them to release harmful chemicals.
And what happens when one of the cups outlives its usefulness? Melamine resin is neither biodegradable nor recyclable. If you want to use a refillable coffee cup, prefer almost anything to the bamboo/melamine combination.
The bottom line for bamboo sustainability
Bamboo is one of the most sustainable of all raw materials. Bamboo sustainability, though, depends on how it’s processed to make products.
With wood, it’s possible to cut boards from a single tree trunk. Making comparable boards from bamboo requires processes I’ll not try to explain, but they have no environmental issues. Therefore bamboo as wood wins any environmental comparison with the same product made from trees.
Bamboo paper is made using the same processes as paper from trees. It is definitely more sustainable than any non-recycled wood paper. I haven’t found good comparisons of bamboo paper vs 100% recycled paper.
The environmental advantage of other bamboo products is more complicated. Manufacturing bamboo fabric uses harmful chemicals, which affect both the environment and the health of the workers who make it. But most other available fabrics use some of the same chemicals. Bamboo’s environmental advantages as a raw material seem to outweigh any disadvantages in production.
Molded bamboo is still 60% plastic. That makes it more sustainable than something 100% plastic. But I can’t recommend it for food service because of the possibility of heat or acid causing harmful chemicals to leach in to the food or beverage.
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]
Truth or trend: is bamboo sustainable? / Bethany Carter, Eco & Beyond. [October 14, 2020]
