As the world grapples with the plastic pollution crisis, bioplastics have emerged as a potential solution, with the Biden administration and European mandates aiming to increase their market share significantly in the coming years. However, recent research has cast doubt on the safety of these plant-based alternatives, suggesting that they may be just as toxic as their petroleum-based counterparts.
Scientists from the University of Gothenburg and the Norwegian University of Science and Technology have conducted studies revealing that bioplastics contain a complex mixture of thousands of chemicals, many of which are highly toxic. Bethanie Almroth, a professor of ecotoxicology and environmental science at the University of Gothenburg, emphasizes that the toxicity is not necessarily due to the plant-based sourcing of the materials, but rather the chemical processes and additives used in bioplastic manufacturing.
In a 2020 study, researchers analyzed various bioplastic products and found that the majority had multiple toxic effects on bacteria. Surprisingly, the type of bioplastic material did not seem to impact toxicity levels, with consumer products tending to be more toxic than the raw pellets. A 2023 study by Almroth and her team further demonstrated that mosquito larvae exposed to leachate from bioplastic-lined cups experienced similar mortality, growth inhibition, and deformities as those exposed to conventional plastics.
These findings have raised concerns about the safety of bioplastic foodware for human use, although more research is needed to confirm the potential health impacts. Martin Wagner, a biologist and professor at the Norwegian University of Science and Technology, states that from a toxicological perspective, there is no difference between conventional and bioplastics when it comes to consumer choice.
The bioplastics industry, represented by the European Bioplastics trade group, has strongly denied the claims made by researchers, stating that bioplastics comply with all relevant laws and regulations. They have also questioned the methods used in the studies and reached out to the University of Gothenburg, resulting in a statement clarifying that Almroth's 2023 study did not definitively attribute the toxic effects to the bioplastic lining itself.
Researchers have called for increased transparency and regulation in the bioplastics industry, citing a lack of information about the chemicals used in these products. The Scientists' Coalition for an Effective Plastics Treaty is advocating for an independent expert body to develop safety criteria for all plastics, including bioplastics, as part of the ongoing negotiations for a global plastics treaty.
While some nations, such as the 65-member High Ambition Coalition, support a ban on "chemicals of concern" in plastics, powerful countries like the United States and China have been resistant to tough binding measures. Almroth and Wagner emphasize that the solution to the plastics problem lies not just in replacing one type of plastic with another, but in reducing overall plastic consumption and demanding better regulation and transparency from companies.