By 2050, there will be more plastic than fish in the ocean. And with plastic taking hundreds of years to decompose, our plastic waste will remain in the ocean, damaging ecosystems, harming marine life and making its way into our food chains.
But what if plastic could dissolve before it did any of this damage? Scientists from the RIKEN Center for Emergent Science Matter and the University of Tokyo have developed a new plastic material that they say “dissolves within hours” and “leaves no residual trace”.
Is the plastic truly biodegradable?
There are already a few biodegradable plastics on the market, as well as alternatives, such as packaging made from seaweed. What makes this solution different? These scientists are confident that their new material is much quicker to break down and doesn’t leave any trace behind. Despite this, it’s as strong as traditional petroleum-based plastics, and with a coating, can be used in the same way. As soon as it’s exposed to salt, it breaks down into its original components, meaning it doesn’t stand a chance in salty seawater. What’s more, the material breaks down in soil, where salt is also present. However, this process takes a lot longer (around 200 hours).
Dissolving plastic could be exactly what our oceans need. But is it too good to be true? We put the question to Rebecca Lahl, co-author of a paper on biodegradable plastics and Head of the Office for Knowledge Exchange at Leibniz Centre for Tropical Marine Research (ZMT).
Lahl explained to RESET that plastic degradation can be chemical, physical or biological. She pointed out that “the term ‘biodegradable’ may be misapplied”. She believes that the plastic’s degradation is more likely chemical or physical, “rather than true biodegradation”. Without empirical data, it was difficult to determine just how fully the plastic could degrade. However, she added that, “the concept should not be dismissed. A genuinely significant material may have been developed. As conventional polymers can persist in seawater for hundreds to thousands of years, materials that break down within months or a few years would already represent a substantial improvement.”
Bringing biodegradable plastics to market
The plastic isn’t commercially available—yet. But, packaging companies in particular have expressed interest in the solution. “If the material performs as described in the article and its environmental claims are supported by data, its commercial potential would be very high,” Lahl told us.
Aside from the plastic currently being formulated in Tokyo, other third-generation biodegradable plastics—that degrade quickly and completely in natural environments—are also in development. But, with a lower performance than today’s long-lasting packaging, the adoption of biodegradable plastics would “require changes in how products are distributed and stored. Items could not remain in vending machines for months or years without degradation, for example.” As well as technological advancements, trading regular plastic for biodegradable options would require strong regulatory frameworks. “In practice, meaningful change will depend on regulations that mandate biodegradability for packaging,” Lahl said.
Reducing plastic waste is the primary solution
From recycling to ocean clean-up technologies, there are many solutions for dealing with existing plastic waste. But cleaning up plastic can’t be the only answer to our marine litter problem. “Effective solutions require extended producer responsibility, emission prevention, behaviour change and reducing overall plastic production and use,” Lahl told us. “As a complementary measure, replacing persistent ‘forever’ plastics with carefully regulated, safe and sustainably designed biodegradable alternatives is particularly promising, [especially] for applications where plastic release into the environment is unavoidable.”
Despite the promise of the proposed solution from Tokyo, it will likely be a while before truly biodegradable plastics come to market. In the meantime, reducing plastic waste has to be a priority. As consumers, we can do our best to limit plastic use in our everyday lives. But, according to Lahl, it’s companies that need to make a major change. “We should first focus on the small number of large brands that dominate marine litter,” Lahl said. “These companies must be engaged directly and held accountable.”
