Climate change, capitalism and disease threaten to deal a fatal blow to the world's rubber trees. Alternative sources are needed before it's too late.
Natural rubber is an extraordinarily strong, flexible and highly waterproof material. He gave us tires for our vehicles, soles for our shoes, gaskets for engines and refrigerators. Insulates our electrical cables, is used in clothing and condoms, soccer balls and simple rubber bands. In the latest pandemic, it was pivotal for PPE worn by doctors, nurses and citizens around the world.
Indeed, rubber is considered a commodity of such global importance that it is included in the list of critical raw materials of the EU.
Unfortunately, there are signs the world may run out of it. There are many factors that jeopardize the world's rubber supplies, leading scientists to seek a solution before it is too late.
Why is rubber so endangered?
The global supply of natural rubber (approx 20 million tons per year) comes almost entirely from smallholders working tiny plots of land in tropical forests. Millions of these workers cultivate plantations in Thailand, Indonesia, China and West Africa, carefully plucking the bark from trees to extract milky white sap that is molded into sheets and dried in the sun. Together, these farmers they provide 85% of the world supply of natural rubber.
But this fragile offer is under threat.
The rubber tree hevea brasiliensis it is no longer cultivated because of the prevalence of South American downy mildew, a tremendous pathogen that has already nearly destroyed local industry in the 30s.
Elsewhere, farmers also face local pathogens such as white root disease and other diseases of leaves that have made the jump from the nearby oil palm plantations. Climate change also affects: rubber production in Thailand has been hit by drought and floods in the last few years.
A growing demand for rubber and a shortage of supply should be good news for farmers, as it would make it more profitable to grow. Unfortunately this is not the case. The price of rubber is set by the Shanghai Futures Exchange, where brokers speculate on the value of this material along with gold, aluminum and fuel. And therefore the price has nothing to do with the cost of production. The price of rubber per ton can vary three times from month to month: in recent years it has remained at very low values.
Low prices force farmers to squeeze their trees for more rubber, weakening plants and exposing them to disease
It's not all. Low prices have also discouraged planting new rubber trees to replace those at the end of their commercial life. Many farmers have completely abandoned the plantations.
Eleanor Warren-Thomas is a researcher at the University of Wales in Bangor, UK, studying the dynamics of rubber plantations. “Palm oil and natural rubber yield the same money per unit of land, but the labor input is higher for rubber,” he says. "As the price of this material is falling, farmers are switching from rubber production to selling timber for a short-term profit, and then cultivate the oil palm".
The combination of these factors brings the world to a point where the supply of natural rubber is out of step with the demand. Already at the end of 2019, the International Tripartite Rubber Council warned that global supply would drop below one million tons (900.000 tons) in 2020, about 7% of production. Then the pandemic struck.
The demand for rubber immediately fell due to Covid, but soon recovered, beating even the most bullish forecasts. When they got out of the block, for example, Chinese citizens bought a huge number of new cars, also given the fears for the safety of public transport. Similar patterns can be seen globally. Demand has outclassed supply since then. And the rubber shortage has become very serious.
Why is natural rubber essential?
The current situation, in short, has spurred the hunt for emergency measures that can save us from a rubber crisis. Why rubber is essential. Although it can be replaced by petrochemicals, natural rubber has unique properties that even these synthetic substitutes cannot match. Natural latex gloves are more tear resistant than nitrile ones, aircraft tires use natural rubber for its high elasticity and heat resistance, which can accumulate due to friction during landing.
How to do it then? Three options
The obvious answer may be to plant more rubber trees. When the rubber shortage starts to hit and prices go up, farmers will be incentivized to clear the tropical rainforest to plant more rubber. Yet it will take a long time before these trees are ready to be exploited: the growth process takes seven years.
We could try to squeeze more rubber from existing plantations. One option is to apply theethephon, a chemical that stimulates the tree to produce more latex sap. Some farmers are reluctant to use it, though, and they do well - too much of this agent can kill trees.
Another option is to give up the plant altogether hevea brasiliensis. The increase in production would be offset by alternatives, not by hevea. Ohio State University is part of the Natural Rubber Alternatives Research Program (PENRA). There, researchers explore possible substitutes.
Dandelion - One of the plants under observation is the Taraxacum kok-saghyz . The gum made from the Kazakh dandelion is chemically similar to the natural one, but it does not contain proteins which cause latex allergies.
Last year, the German research institute Fraunhofer ISC presented a tire called Biskya, from the German abbreviation for biomimetic synthetic rubber. Made of dandelion rubber, it has a higher wear resistance than typical rubber. Varieties and cultivation techniques are also studied including hydroponics and vertical farms, to help make dandelion gum a commercial reality. With their systems, sap-filled dandelion roots can be harvested five times a year.
Guayule - It is a woody shrub that grows in the deserts on the border between the USA and Mexico. It was introduced briefly During the Second World War.
As part of the Emergency Rubber Project, a small army of scientists and workers worked hard to cultivate 13.000 hectares of guayule, which it produced about 400 tons of rubber every month. Today, only two companies produce rubber commercially from guayule. The tire manufacturer Bridgestone maintains a 114-hectare experimental plot of guayule in Arizona, which produced its first tires in 2015. He was assisted by the Italian oil giant Eni, which operates a guayule trial plot in Sicily .
If at least 10% of the rubber used around the world came from alternative sources, we could quickly increase it in case of emergencies. Arizona alone has over three million acres of desert land suitable for guayule cultivation. The rubber crisis is a once-in-a-lifetime opportunity to attract investment in these alternatives.
The urgency to intensify these efforts will grow ever greater.
Global demand for natural rubber will continue to increase. Developing nations will be driving forces: Imagine a future where every African family legitimately chooses to buy two cars, like Western families today. Fundamental for this to save the rubber and its use.
In summary: we need to help farmers to improve production. We need to teach them to also cultivate alternatives, looking for the best and least harmful ones for the territory, in order not to increase the deforestation. It is necessary for institutions to introduce a fixed minimum price for rubber, supporting production, as is done for fair trade programs (I am thinking of coffee and cocoa).