Typically, when people think of the word ‘natural’, a string of positive words follow. Something that is natural is considered healthier and greener. What if this wasn’t always the case? What if something from a forest could be more environmentally damaging than if it came straight off the conveyor belt of a factory? Instinctively, one could think of natural rubber to be a greener solution than synthetic rubber. What if the opposite were true, and the potential effects on the environment of naturally produced rubber were more detrimental?
Natural rubber first appeared in South America. Hevea Brasiliensis trees, nicknamed ‘rubber trees’, ooze a white fluid called sap. Once dry, the sap becomes a rubbery, bouncy material. Over time applications were discovered, the most significant being tyres, bourgeoning a world demand. In the last forty years, its global consumption has doubled and shows no sign of stopping.
To match world needs, this south American tree was imported to Africa and South Asia. Tropical forests were subsequantly destroyed and filled with rubber trees. Deforestation is a great threat to the biodiversity in these areas: it simultaneouslty reduces plant diversity and forces animals out of their habitats. It is also raising concerns about the inefficiency of these forests to absorb carbon dioxide.
“Up to one fifth of the Amazon rainforest is emitting more CO2 than it absorbs, new research suggests.“Gabriel Gatehouse, BBC
By wiping the land clean of vegetation, one prevents CO2 from being absorbed. In fact, the Food and Agriculture Organization of the United Nations, reported that deforestation makes up nearly twenty percent of all greenhouse gas emissions.
Furthermore, natural rubber must be protected before, during and after its production. Naturally, vegetation is subject to disease. To avoid this, toxic anti-fungicides are used. During production, measures are taken to avoid mould growth, while also spraying the final product with chemicals. Creating forests solely made up of one type of tree, increases the likelihood of a parasite spreading. It was precisely these problems – a fungal infection contaminating trees in Brazil – that led the natural rubber industry in South America to crash.
The production of rubber in a lab spurred during the Second World War. Synthetic rubber is currently made by extracting petroleum from the ground. It is refined and broken down to retrieve certain molecules, like isoprene. Linking isoprene molecules together produces rubber.
The main disadvantage in the production of man-made rubber is the use of crude oils, a large contributor to global warming. It might sound odd to suggest this as a greener solution. However, there is an argument to be made in favour of synthetic rubber. Its production doesn’t require a certain climate or more importantly, eradicating forests. The detrimental effects on the environment, along with the chemicals needed for the production of natural rubber should be a strong argument.
A study showed that tyres made from synthetic rubber opposed to natural rubber, uses ten percent less rolling resistance, leading to improvements in fuel efficiency. Futhermore, ethical questions arise relating to the lack of regulations surrounding labour, land and production. Today’s scientists are finding more sustainable and socially responsible ways of producing isoprene from plant-based sources.
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