The growing market for rubber is a major, but largely overlooked, cause of tropical deforestation, new analysis shows. Most of the rubber goes to produce tires, more than 2 billion a year, and experts warn the transition to electric vehicles could accelerate rubber use.
The elephants are gone. The trees are logged out. The Beng Per Wildlife Sanctuary in central Cambodia is largely destroyed, after being handed over by the government to a politically well-connected local plantation company to grow rubber.
In West Africa, the Luxembourg-based plantations giant Socfin has been accused in recent weeks of deforestation and displacing Indigenous people around its rubber plantations in Nigeria and Ghana.
Meanwhile, on the heavily deforested Indonesian island of Sumatra, tire multinational Michelin and a local forestry company raised $95 million worth of green investment bonds on the promise that they would reforest bare land with rubber trees. But the NGO Mighty Earth has found that much of the plantation went ahead on land from which natural forest had been removed as recently as a few months before by a subsidiary of the local company.
These are just three examples among hundreds of one of the biggest, but least discussed, causes of tropical deforestation. The spread of rubber plantations is driven primarily by our demand for more than 2 billion new tires each year. The full devastating impact of this has been exposed by a new analysis of high-resolution satellite images that can, for the first time, distinguish rubber plantations from natural forests.
Rubber as a crop is a worse deforester than coffee or cocoa and is now closing in on palm oil for the top spot.
But even as the true environmental cost of the ubiquitous rubber tire is being exposed, the damage could be about to escalate sharply. The new culprit is electric vehicles. Being substantially heavier than conventional vehicles, they reduce the life of a tire by up to 30 percent, and so could raise demand for rubber by the same amount.
Natural rubber is a milky latex harvested manually by tapping the bark of the Hevea brasiliensis, a tree originally from the Amazon that is now grown widely in plantations, especially in Southeast Asia. World demand has been rising by more than 3 percent a year. But with no sign of increased yields on plantations, that requires ever more land to keep pace.
Yet there has been little outrage. While growers and processors of other tropical commodity crops, such as soy, beef, palm oil, cocoa, and coffee, are under ever greater pressure from both regulators and consumers to show their products are not grown on land deforested to accommodate them, rubber has escaped public attention. When did you last see deforestation-free rubber tires advertised?
One reason for this environmental blind spot is that the truth has not been able to be seen by the remote-sensing systems used to track changing land use in much of the tropics. Unlike with other commodity crops, even the most assiduous analysis of satellite images of forest regions has been unable to distinguish the foliage of monocultures of rubber trees from the canopies of natural forests.
Until now.
A new international analysis published in October has for the first time used high-resolution imagery from the Sentinel-2 earth observation satellites, launched by the European Space Agency, to accurately identify rubber plantations. “The results have been sobering,” says lead author Yunxia Wang, a remote-sensing specialist at the Royal Botanic Garden Edinburgh.
She has found that between 10 and 15 million acres of tropical forests, an area larger than Switzerland, has been razed in Southeast Asia alone since the 1990s to feed our hunger for rubber. This is three times more than some previous estimates used by policymakers, she says. It makes the crop a worse deforester than coffee or cocoa and closing on palm oil for the top spot.
Tires on electric vehicles can wear out 30 percent faster than on conventional models, tire companies note.
Wang found that more than 2.5 million acres of this forest loss has been in Key Biodiversity Areas, a global network of natural sites identified by ecologists as critical for protecting endangered species. And she concluded that the recent boom means rubber plantations now occupy at least 35 million acres of Southeast Asia, where Thailand, Indonesia, and Vietnam are the world’s top three natural rubber producers.
Rubber’s deforestation footprint is also rising fast in Cambodia, says Wang. The country has lost a quarter of its forests in the past quarter-century, with at least 40 percent of new rubber plantations established in forests cleared for rubber production, including the Beng Per Wildlife Sanctuary. And it seems likely there will be many more to come. The Cambodian government has allocated 5 percent of the country for rubber growing, according to Global Forest Watch.
You can see why. Natural rubber is used widely in everything from condoms to sportswear and toys to industrial machinery. But more than 70 percent makes the 2.3 billion new tires the world buys each year. With ever more cars on the roads, demand continues to surge.
Rubber resin collected from a tree near Lubuk Beringin, Indonesia. Tri Saputro / CIFOR
Early this year, Eleanor Warren-Thomas, a conservation scientist at Bangor University in Wales, and colleagues estimated that up to 13 million acres more land will be needed to meet rising rubber demand by 2030. And that, she says, is before considering the potential impact of the switch to electric vehicles.
Electric automobiles are typically a third heavier than equivalent combustion-engined vehicles, largely because of the weight of their batteries. Also, they can accelerate and brake faster, which adds further to wear and tear on tires. Tires are being developed for e-vehicles that will be more robust. But meanwhile, tire companies such as Goodyear say traditional tires on electric vehicles can wear out 30 percent faster than on conventional models.
The rubber tree was one of the first discoveries made by Europeans in the Americas. Christopher Columbus spotted how natives on the Caribbean island of Hispaniola milked its bark to make rubber balls for their children. But it was another 300 years before industrialized rubber production began, first for waterproofing cloth and later for tires. This unleashed a boom in extraction from wild trees in the Amazon rainforest. Tens of thousands of natives were pressed into service to tap the trees, while their traders grew so rich that they turned the Brazilian river port of Manaus into “the Paris of the tropics.”
Eventually, European botanical entrepreneurs took the Amazon seeds and set up plantations in British Malaya, French Vietnam, and Dutch Indonesia, undercutting wild harvesting. In 1926, America’s Harvey Firestone broke a European price cartel by establishing what remains the world’s largest rubber plantation, covering 4 percent of the West African state of Liberia and boasting its own golf course, Mormon church, and yellow American school buses.
“There is a low public awareness that rubber is a crop, let alone a crop that drives deforestation,” says a researcher.
But today such large plantations grow only around 15 percent of the world’s rubber. The rest is produced by around 6 million independent smallholders, who sell via complex networks of middlemen and processors to supply a handful of major tire manufacturers, headed by Michelin, Bridgestone (owners of Firestone), Continental, Goodyear, and Pirelli.
In 2017, several tire and car manufacturers reacted to trends in other commodity-crop businesses by promising to deliver much more sustainable rubber tires. Many subsequently joined the Singapore-based Global Platform for Sustainable Natural Rubber, a collaboration between corporations, academics, and NGOs. But to date there has been little outcome from the promises. The platform hopes to publish next year an “assurance model” designed to “validate member companies’ adherence to their commitments to environmental sustainability.” But so far some of its members concede that it has not gained the same traction as its equivalents in industries such as palm oil.
Tire manufacturers and the Global Platform explain that the fractured and dispersed rubber supply chain makes it hard for them to know precisely where their rubber comes from, much less to root out deforestation. Sam Ginger, who researches the rubber industry at the Zoological Society of London, a science-based charity based at London Zoo, agrees there is a “void of traceability.” But, he says, there is also a void of ambition in the industry.
A rubber tree plantation in North Sumatra, Indonesia. Maskur Has / SOPA Images / LightRocket via Getty Images
Ginger compiles a regularly updated database on the environmental activities of the industry’s major players. His most recent assessment, published in March, found a huge gap between their policies and practice. While 69 percent of the surveyed companies have policies requiring zero deforestation from their suppliers, “only 7 percent of companies publish evidence that they regularly monitor deforestation in supply operations,” he told Yale Environment 360, “And none disclose that they monitor their entire supply chains.”
Why the slow progress? One reason is a lack of public pressure. “Despite the ubiquity of rubber products, there is a low public awareness that rubber is a crop, let alone a crop that drives deforestation,” says Ginger. As a result, “the industry has been able to continue expansion with little scrutiny, while the spotlight has been focused on other commodities, such as palm oil and soy.”
So, what can be done? One route would be through the Forest Stewardship Council (FSC), which certifies deforestation-free forestry and forest products. Again, results have so far been fitful. Currently there is only one tire marketed as FSC-certified: a Pirelli tire launched in 2021 for a single BMW model. (Pirelli did not respond to questions about where this rubber is grown, other than to say it is from smallholders.)
One way to reduce pressure on the world’s rainforests would be to use more synthetic rubber and less natural rubber.
One early advocate of a sustainable approach was the Vietnam Rubber Group, a state-owned planting and processing company. But the company reported last year that just 2 percent of its 1.35 million acres of rubber plantations were certified.
There is also confusion about what sustainability objectives the tire industry should adopt, and how important preventing deforestation is to that agenda.
Typical tires are today made of roughly equal amounts of natural rubber and synthetic rubber from mineral oil, a fossil fuel product. Synthetics are essential for some tire characteristics. So, one way to reduce pressure on the world’s rainforests would be to use more synthetics and less natural rubber.
But if anything, the trend is in the opposite direction. Some manufacturers appear to be prioritizing the phaseout of the fossil fuel footprint of their products, even at the expense of worsening deforestation. Michelin, for instance, says it wants to have all its tires made of 100 percent “biosourced, renewable or recycled” rubber by 2050 and attributes progress so far in part “to a greater use of natural rubber.” Whether or not the trade-off is an environmental gain will depend on both sources of supply and environmental priorities.
A rubber plantation in western Ghana owned by Ghana Rubber Estates Ltd. Cristina Aldehuela / AFP via Getty Images
With the industry seemingly unable or unwilling to deliver on zero deforestation, government regulation could break the logjam. Leading the way is the European Union, whose 27 members use about a tenth of the world’s rubber.
Last December, the EU defied concerted rubber-industry lobbying to add rubber to a list of tropical commodity products, including palm oil, beef, cocoa, soy, coffee, and wood, that importers will be required to demonstrate are deforestation-free under its upcoming Deforestation Regulations. Ginger says there are serious questions about whether the industry is ready or able to comply with the new rules.
Rubber is also among crops listed in the similar Forest Act in the U.S., which is currently stalled in Congress, and in planned U.K. legislation. But both would only penalize those importing rubber grown on illegally deforested land, says Ginger. Deforestation deemed legal by host countries would still be allowed.
By far the biggest rubber market today is China, which consumes more than a third of the world’s rubber. Its demand has driven much of the recent growth in rubber cultivation in Southeast Asia, and China has begun taking a leading role in the international market. State-owned ChemChina bought tire giant Pirelli in 2015, and this year the China Hainan Rubber Industry Group purchased a controlling stake in the word’s bigger rubber trader, Singapore-based Halcyon Agri. While China’s Chamber of Commerce can be credited with producing the earliest draft rules for sustainable rubber production, there has been little buy-in by its companies to date.
Some scientists advocate agroforestry, noting planting rubber among other crops can deliver yields as good as plantations.
What will shift the dial?
Ginger says more transparency in supply system could help drive up standards. Increasing demand could be met from existing plantations, he argues, if big-brand companies would identify and support smallholders to achieve better yields.
Warren-Thomas says another approach is to encourage the adoption of agroforestry in place of plantations. She has studied how this might work in southern Thailand. Planting rubber amid food and other tree crops can deliver yields as good as monoculture plantations, she says. Pilot projects are happening. In Sumatra, Pirelli and BMW, in partnership with Birdlife International and other environment groups, are supporting rubber agroforestry as a means to protect the nearby Hutan Harapan forest.
Warrern-Thomas believes controlling demand is just as important. Recycling of used rubber tires could help, especially by turning them back into new tires, rather than current lower value uses such as bouncy playground surfaces. But the highest priority should be reducing our reliance on the car through improved public transport, she says. “Cars use much more rubber per-person-kilometer than buses.”
And a transition to electric vehicles could make that difference even greater. So if we simply accept the idea that e-vehicles solve all our environmental dilemmas over transportation, we run the risk of unleashing a new round of deforestation.
By Erick Sharp, CEO and founder, ACE Laboratories
The rubber industry is a dynamic market sector that has grown and changed dramatically over the years through innovation and discovery. A number of rubber industry trends are impacting industrial and consumer product manufacturing worldwide. These trends include growing demand for synthetic rubber, the rising popularity of electric vehicles (EVs), ongoing supply chain disruptions, and consumer demand for sustainable rubber products and materials.
While the natural rubber market remains strong, synthetic rubber is growing in popularity.
A variety of factors are driving increased demand for synthetic rubber over natural rubber.
One advantage of synthetic rubber over natural rubber is the fact that it can be produced domestically on most continents. This is especially crucial when unpredictable factors make it difficult to source rubber materials or slow down procurement timelines. Rubber material supply may be affected by:
● War. In the beginning of World War II, the United States was cut off from the natural rubber supply in southeast Asia. The country was forced to scramble for alternatives, which led to a massive collaborative effort to produce synthetic rubbers for military and commercial use.
● Natural disaster. In recent decades, devastating fires have struck rubber plantations in Liberia, India, and Thailand, to name a few. Because rubber trees, or Hevea brasiliensis, take seven years to reach full maturity, fires and other disasters have lasting consequences for the global rubber supply. Recovery can be a years-long process.
● Supply chain disruptions. Virtually every industry was affected by the COVID-19 pandemic, and the rubber industry was no exception. Disruptions included labor shortages, raw material shortages, and production and distribution slowdowns, as well as major price fluctuations.
Ninety percent of the world’s rubber supply comes from Asia. Synthetic rubber, on the other hand, can be produced domestically on most continents. With the lingering effects of the COVID-19 pandemic still affecting the entire rubber industry, synthetic rubber is a more accessible option in many situations.
Synthetic rubbers also are highly customizable and can be engineered to outperform natural rubber in specific areas. This might include abrasion, thermal resistance, chemical resistance, and processability. Not all synthetic rubbers exceed natural rubber in these areas, but for some applications, a customized synthetic rubber might be the superior choice.
Consumer demand for EVS is growing in the United States, Europe, and China. In the past few years, multiple countries, including China and the United States, have announced longterm goals to increase the percentage of EVs on the road. This shift toward electrification is already causing significant ripple effects in the rubber industry.
Internal combustion engine (ICE) vehicles generate heat and consume oil in operation. As a result, ICE vehicles have traditionally utilized a lot of nitrile rubber due to its excellent heat and oil resistance properties. Because EVs run without oil and produce heat very differently than ICE vehicles, these properties are less important.
When it comes to rubber materials in EVs, the greater focus is on thermal insulative values, electrical conductivity, and weatherability. Lightweight materials also are very important in EV production.
Due to the differences between ICE vehicles and EVs, there is a shift away from nitrile rubber and toward ethylene propylene diene terpolymer (EPDM), silicone, thermoplastic elastomers (TPE), and thermoplastic vulcanizates (TPV).
While the automotive industry is seeing worldwide demand for electric vehicles, the Asia-Pacific region - especially China - represents the largest share of EV sales. A significant portion of EV production and manufacturing is located in Asia as well. As a result, rubber demand in Asia is trending upwards.
Pricing, material shortages, and allocations remain major issues for the rubber industry. Many companies are struggling to get the materials they need, especially if their competitors or other industries are also attempting to source.
In some cases, companies are turning to alternative suppliers for materials. These materials need to be recertified by an independent, third-party testing laboratory to maintain compliance and ensure quality. Efficiency is critical to minimize any delays in production.
Limited supply and massive price fluctuations have forced some companies to switch to completely different materials. This often requires adjustments to compound formulations to ensure that the alternative material can match the performance attributes and quality of its predecessor. Many companies rely on independent rubber testing labs to mix and test multiple experimental formulations in a short time frame so they can choose a new one quickly and get back to full production.
A growing number of industries are striving to meet growing consumer demand for environmentally friendly products and practices. In the rubber industry, this applies to both rubber materials and the overall performance of rubber products.
Recycling rubber is an effective way to extend the life of rubber materials and is a priority for many key players in the rubber industry. Recycled rubber is a sustainable alternative to new materials, and many industries are finding creative ways to use it. Hospital flooring, playground and landscaping mulch, and rubberized asphalt are commonly made with recycled rubber. Recycled rubber also is a popular choice for infill on synthetic turf, indoor tracks, and other athletic surfaces.
Recycled rubber often comes from a variety of sources. It is critical to test each batch of recycled rubber for hazardous materials, such as mercury or lead, to ensure that the material is safe for commercial use. A rubber testing laboratory can utilize sophisticated techniques to identify and quantify any impurities to determine whether recycled rubber meets safety standards.
Another key sustainability trend in the rubber industry relates specifically to the performance of rubber products. The most obvious example is tires. A key performance attribute of a car tire is rolling resistance, which refers to the energy needs to keep the tire rolling consistently. The rolling resistance of the tire can have a significant impact on its overall fuel economy. Rolling resistance is meaningfully impacted by the rubber compound utilized in the tire tread. The tire and rubber industries have invested ample resources into research and development in search of an optimized tire tread compound that reduces rolling resistance - and thus improves fuel economy - without sacrificing other key performance attributes. If adopted on a global scale, an optimized tread compound could make a meaningful difference in worldwide fuel consumption. This industry-wide pursuit of a greener tire has had ripple effects throughout the rubber industry. n
Reprinted with permission from ACE Laboratories, www. ace-laboratories.com.
Erick Sharp is the founder of ACE, establishing it in December of 2014. He has over 20 years of experience in the rubber industry. During that time, he has held technical and operational roles within international companies. Sharp has a degree in industrial engineering.