Assess and reduce toxic chemicals in bioplastics

Assess and reduce toxic chemicals in bioplastics To promote a circular economy and mitigate pollution, the bioplastics industry has begun to phase out polymers derived from petrochemicals (1–3). This action is a positive step, but it doesn’t affect the many bioplastics on the market, which also contain potentially harmful additives. Given that bioplastics will likely replace polymers, it is crucial to determine which bioplastics cause the least harm. Components of bioplastics can leak into the environment. After disposal, weathering and ultraviolet degradation lead to additional release of chemicals (4). When determining the safety of plastic materials, it is important to consider that such leakage could have adverse effects on ecosystems, wildlife, and humans (5–8). Discarded plastics often end up in the ocean, where chemicals leaking into the aqueous environment are toxic to marine life. Additives such as phthalates from starch- and cellulose-based bioplastics can also leak into marine environments through wastewater and runoff from landfills. The chemicals affect bioluminescent bacteria and the development of sea urchin larvae (5–7). Bio-cups, bio-polyethylene bottles, and bioplastic supermarket bags are produced with polylactide (PLA), a polyester derived from renewable biomass. PLA contains chemicals of emerging concern (CECs), such as bisphenol A, that cause dose-dependent increases of malformed mussel larvae (8). More information about the CECs in bioplastics is urgently needed. No protocols are available to characterize either the chemicals or the leachate of chemicals from conventional and bio-based plastics (9), making evidence-based, environmentally responsible management impossible. Manufacturers of plastic items and their consultants should be required to test for molecular, organismal, and population-level effects and make public the risks of each type of both conventional plastic and bioplastic (10). Integrated chemical and biological approaches should be used to assess the risks associated with low-level exposures to CECs released by bioplastics as well as their possible combined effects in mixtures. Assessing the toxicity of CECs that migrate from bioplastics into the surrounding environment could help determine how to prevent unexpected adverse health outcomes (11). Instead of replacing one harmful material with another, the bioplastic industry and researchers should work together to identify the safest and most sustainable plastic alternatives (6). Creating and prioritizing the production of nontoxic materials with a low carbon footprint could lead to a reduced need for landfills and less ocean plastic waste.