A Close Look At Bamboo Sunglasses - Sustainable or Not?
This post was last updated in 2023
Sunglass frames can be made from a whole range of materials – plastic, metals, recycled plastics and even plant-based plastics. Add to the list, bamboo.
This is not a niche product as there are quite a few companies selling bamboo sunglasses. And they often claim to be the sustainable alternative.
But are bamboo sunglasses sustainable?
On the whole, bamboo sunglasses are more sustainable than plastic or metallic sunglasses. But this does depend on where the bamboo is sourced. Transportation of the product is an important consideration, as well as the growing practices in the country where the material is sourced.
Bamboo is often claimed to be a sustainable source material for a wide variety of products – not just sunglasses. It grows at a rapid rate and is renewable. But if you examine these claims closely, you find the story is not so simple and the sustainability claims don’t always hold.
In this blog post I explore this issue further, focusing on sunglasses and addressing the following questions:
How are bamboo sunglasses made?
Bamboo sunglasses are generally made from 3 – 5-year-old bamboo. The basic steps to make bamboo sunglasses are as follows:
- The harvested bamboo is cut into sections
- A machine cuts the bamboo sections into the frame and arm shapes
- The pieces are sanded down and polished to get a smooth finish (there is no need for chemicals at this stage)
- Holes are drilled into the frames and arms for joining
- The pieces are joined with metal hinges
- Lenses are inserted into the frame
- The end product is polished and packaged
This is the process outlined in the following video made in 2019:
Retailers of bamboo sunglasses tend not to publish who grows or manufactures the bamboo used in their frames, so it is difficult to confirm how applicable this general process is to the market as a whole.
I would imagine the level of labour and machine work would vary across different companies.
However, based on other accounts of the bamboo sunglass-making process, the steps outlined above are a good representation of how bamboo sunglasses are made.
What are the benefits associated with bamboo products?
Bamboo has several benefits when used as a source material including its strength and flexibility, the fact that it grows faster than most other plants, and it is renewable as it doesn’t need replanting.
Here’s a summary of all the different ways that bamboo is a sustainable and useful material source:
1. It is a strong material that can be used to produce a variety of items
- Bamboo is stronger than steel – the tensile strength of steel is 23,000 PSI while the tensile strength of bamboo is 28,000 PSI
- Bamboo can be used to produce a variety of items like building materials, furniture, irrigation systems, weapons, boats and bridges. And many household items like forks, spoons, bowls, plates, cups, straws, toilet paper, clothing and sunglasses.
2. Bamboo grows fast and can improve soil health
- Bamboo grows fast – it can take 3-8 years to produce bamboo that is suitable for most purposes, compared to 6-100 years to grow timber suitable for harvesting (intensively managed eucalyptus can be harvested in little as 6-8 years but most other hardwoods take longer to be harvested)
- Bamboo is renewable – only the top of the plant is harvested, allowing the plant to renew in less than 10 years
- Bamboo can grow in areas that are often difficult to plant in because of its deep root structure
- When done right, producing bamboo enriches the soil structure as the plant top is harvested, not the whole plant. As such roots remain undisturbed, allowing beneficial microorganisms to flourish, improving soil health as a result
3. Bamboo generally has a low carbon footprint and uses less energy to produce
- Bamboo produces more oxygen – when compared to trees that cover the same area of land, bamboo produces 35% more oxygen
- Bamboo sequesters a significant amount of carbon dioxide – it can absorb around 12 tonnes of CO2 per hectare per year. And this is why growing bamboo is considered a key solution for reducing carbon emissions, according to Project Drawdown.
- Producing bamboo has a lower carbon footprint when compared with an equivalent amount of wood, steel or plastic
- Producing bamboo takes less energy and other resources compared to wood, steel and plastic
- It is claimed that bamboo needs only natural rainfall to grow.
4. Bamboo is low waste
- The waste products in bamboo production are biodegradable by microorganisms and sunlight and not harmful if released back into the environment
- At the end of their life, products made from bamboo are biodegradable and compostable
Some would claim that bamboo does not need fertilizers or pesticides to yield significant quantities, however, I have not found any accounts that support this claim. Even when it comes to growing household quantities of bamboo, bamboo is noted as a hungry plant.
This is not the only claim about bamboo that doesn’t hold. Even some of the claims noted above, which have come from research papers publicly available on the subject, aren’t always true.
Rather it represents the potential benefits of bamboo as a material source – benefits that can be realised if grown responsibly – but can disappear if it is grown in an unsustainable manner.
What are the negative impacts of bamboo?
While there are ways to grow bamboo sustainably, if not managed correctly bamboo can take over native forest land, lead to a decrease in biodiversity and soil health and require the use of fertilisers and pesticides. This is particularly a problem for bamboo grown in China.
China is known to have the largest and fastest-growing bamboo export market in the world ($60,787.31K, 108,145,000 Kg in 2019).
The Chinese market far exceeds any other country and it is growing fast:
It is a fairly unregulated industry in China, with very few standards in place for environmental protection.
And it is likely the rapid unregulated growth of this industry that has lead to the following practices:
- Bamboo is grown in intensive monoculture plantations across many parts of southwest China.
- One species dominates the market – the Moso bamboo. Moso bamboo currently accounts for more than 80% of China’s bamboo area.
- Native forest lands are being cleared in China to set up bamboo plantations. About 23% and 30% of the forests in China shifted to bamboo plantations during the two periods of observation [1984-1995 to 1995-1999]
As a result of these practices, the following environmental impacts have been observed:
- Bamboo plantations have simplified the structure of the forest and decreased the species richness and biological diversity of tree, shrub, and herb layers. For example: “In Hunan, 15 species of birds were observed compared to 35 species in nearby mixed forests. In Sichuan, 12 species were observed compared to 34 species in nearby mixed forests”.
- Bamboo plantations have decreased soil microbial activity, biodiversity and the soil’s ability to retain water.
- There is a reduced capacity to provide important ecosystem services including erosion control and nutrient cycling.
- There is reduced resilience to external threats including pests, disease and extreme weather events. This is why pesticides are often used in bamboo production.
A review by Dovetail Partners (a non-profit research organisation) found many of the claims commonly made about bamboo do not hold when bamboo is grown on plantations in China.
They found:
- Bamboo yields can decrease in the long run – it’s only in the short term that you can expect high yields from bamboo plantations
- Bamboo requires high levels of water – while it seems they can survive on natural rainfall alone, this is only true if the levels of rainfall levels are naturally high. They note: “Monopodial bamboos prefer sites with a warm, moist climate and annual precipitation over 1,200 mm”. That’s a lot of water if you are not growing in climates with high levels of rainfall.
- Bamboo requires some level of fertilisation to grow. “It is estimated that, on average, farmers annually apply 200kg (440 pounds) of fertilizer (mainly nitrogen) per hectare to bamboo plantations.”
And one final component often overlooked is the issue of transportation. Bamboo has to travel large distances to get into the hands of the import markets. As you will see in the next section, transportation is a key component in determining the carbon footprint of bamboo products.
Are bamboo sunglasses sustainable?
On the whole, bamboo sunglasses are more sustainable than plastic or metallic sunglasses. But this does depend on where the bamboo is sourced. Transportation of the product is an important consideration, as well as the growing practices in the country where the material is sourced.
Bamboo, even when not produced in ideal conditions, has several benefits over plastic or steel including its:
- low energy consumption
- low carbon footprint
- low impact at the end of its life (since it is biodegradable and compostable)
Considering that the production of bamboo sunglass frames involves very few additional chemicals, it is likely these benefits extend to bamboo sunglasses.
But transportation is a key consideration when comparing products and wanting to make a choice that is more sustainable.
This was apparent in a study comparing the carbon footprint of straws made from bamboo, paper, plastic and steel. Here are the results of the study:
Bamboo
| Output | Embedded Energy | Carbon Dioxide Emissions |
|---|---|---|
| Materials | 9.10 kJ/straw | 0.55 g CO2/straw |
| Transportation | 745.23 kJ/straw | 38.27 g CO2/straw |
| Disposal | 0.07 kJ/straw | 0.05 g CO2/straw |
| Total | 754.41 kJ/straw | 38.87 g CO2/straw |
Paper
| Output | Embedded Energy | Carbon Dioxide Emissions |
|---|---|---|
| Materials | 3.61 kJ/straw | 0.53 g CO2/straw |
| Transportation | 11.43 kJ/straw | 0.85 g CO2/straw |
| Disposal | 0.01 kJ/straw | 0.01 g CO2/straw |
| Total | 15.05 kJ/straw | 1.38 g CO2/straw |
Plastic
| Output | Embedded Energy | Carbon Dioxide Emissions |
|---|---|---|
| Materials | 20.17 kJ/straw | 1.10 g CO2/straw |
| Transportation | 6.99 kJ/straw | 0.34 g CO2/straw |
| Disposal | 0.02 kJ/straw | 0.01 g CO2/straw |
| Total | 27.18 kJ/straw | 1.45 g CO2/straw |
Steel
| Output | Embedded Energy | Carbon Dioxide Emissions |
|---|---|---|
| Materials | 820.00 kJ/straw | 140.91 g CO2/straw |
| Transportation | 1598.92 kJ/straw | 76.24 g CO2/straw |
| Disposal | 0.02 kJ/straw | 0.02 g CO2/straw |
| Total | 2418.94 kJ/straw | 217.16 g CO2/straw |
The carbon footprint of the bamboo straw was much higher overall. However the main reason for this was transportation – the bamboo and steel straws were shipped from Asia to America, whereas the plastic came from the UK and the paper was locally sourced.
If you look at the carbon footprint of materials, bamboo is low, second only to paper.
So as a material source, bamboo is a more sustainable option compared to plastic or steel. And it’s on par with paper.
However, this is a very simple way of assessing sustainability. The carbon footprint of a product is one aspect to consider. Other aspects include the long-term environmental impacts of bamboo production and the impact of the product at the end of its life.
(Note: While the straw study looked at “disposal”, it was only assessed in terms of transportation to landfill/ recycling / composting sites – it did not measure the overall carbon footprint at the end of the product’s life).
Determining which material is sustainable when compared to another is a difficult process because of all the different factors involved.
The potential negative impacts of bamboo need to be kept in mind. These negative impacts are long-term and difficult to measure. With no single measure that can compare the potential environmental impact of bamboo plantations vs the long-term environmental impacts of plastics (as an example), it can be difficult to objectively determine whether one product is more sustainable than another.
But on balance bamboo does seem to be the sustainable alternative – from a carbon sequestration point of view, bamboo is a winner. And if grown right, bamboo has several advantages over products made from plastic or metals. It is not a resource-intensive product and it is largely biodegradable at the end of its life.
Hey, if you are not convinced that bamboo is a sustainable option, especially when given the concerns raised, there are other options you can consider.
Of course second-hand glasses are your best choice, over buying anything new. I had a great experience with this and have some suggestions on this, covered in this blog post: Sustainable Sunglasses – What to Look Out For
Or consider sunglasses made from recycled plastics. You can read more about this here: Recycled Plastic Sunglasses – Innovations Worth Supporting.
What should you look out for when buying bamboo sunglasses?
When looking to buy bamboo sunglasses and ensure your purchase is a sustainable one, the key is to ensure the bamboo is sustainably produced. And certification seems to be the easiest way for a consumer to ensure there are some checks in place on how bamboo is produced.
The one certification that appears on bamboo products is FSC certification. This is now available for bamboo products however, it is not commonplace. Also, FSC certification is largely criticised because it is costly to achieve and therefore creates a barrier to small landholders, which is where the majority of the bamboo is sourced.
FSC certification is typically obtained by large-scale operators and it is questionable how sustainable these operations are. And there are reports that FSC certification is less than reliable, particularly in areas where there are very few environmental standards.
There is also the Sustainable Agriculture Standard certification, provided by the Rainforest Alliance. However, this certification is very rare and hard to find in this market.
As a consumer, there is very little to go by other than FSC certification. While not ideal, it is the best assurance we have that some standards have been applied to minimise the impact on the environment.
It’s not an easy question to answer – are bamboo sunglasses sustainable? So what I have done is provided a summary of both sides of the argument, so you can judge for yourself or at least appreciate there is no one clear answer.
Overall if you are wanting to buy new sunglasses, bamboo is not a bad option. And there are other options you can consider if you haven’t already (as noted above)/
The most important point is to ensure you purchase the highest quality that you can afford and the purchase suits your needs. Because the most sustainable purchase is one that will last.
xxx Tahsin
After more information? You may be interested in....
Don’t Throw Them Away – Practical Uses for Your Old Glasses – if you have old eyewear, don’t trash it! Explore this guide, which covers options to repair, reuse and recycle glasses.
Sustainable Sunglasses – Know What to Look Out For – learn about the different options available to make your sunglass purchase a sustainable one.
9 Sustainable Sunglass Brands Worth Checking Out – for a list of Australian brands making sunglasses from sustainable materials and a summary of the pros and cons of each.
Sustainable Choices for Your Eyewear – Your Options Covered – for information on reusing old frames and lenses and where to get glasses second-hand.
Replacing New Lenses in Your Old Frames – Is it Worth it? – for further information about getting new lenses into your existing frames, in particular, how much this will cost
7 Sustainable Eyewear Brands Worth Checking Out – for a list of Australian brands making prescription glasses from sustainable materials.
Plant-Based Sunglasses – What Are They Made From Really? – read this if you want to know what “plant-based” sunglasses really mean and what makes them a sustainable option.
Recycled Plastic Sunglasses – Innovations Worth Supporting – learn about the types of recycled plastics used in sunglasses and the different brands that sell this sustainable option.
Recycled Metal Sunglasses – From Waste to Wearable – discover the unusual source materials used in recycled metal sunglasses and the studies that show they are a sustainable option.
