A new study shows that certified biodegradable materials break down in the environment, unlike conventional plastics.
A new report published by BB-REG-NET has found that whilst biodegradable materials do fragment into microplastics as part of their breakdown process, these particles are transient and continue to biodegrade through microbial activity, unlike conventional plastics, which persist indefinitely in the environment.
BB-REG-NET says the report, ‘Addressing Persistent Plastic Pollution: The Case for Biodegradable Solutions’, shows that certified biodegradable plastics offer a viable pathway to reducing long-term microplastic accumulation in the environment.
The report examined key applications where biodegradable materials are used in open environments. Evidence from case studies in agriculture, forestry, and composting demonstrates that when properly managed under supportive regulatory frameworks, biodegradable plastics break down at a rate similar to their introduction into the environment, thereby preventing long-term accumulation.
The research also shows that biodegradable agricultural mulch films can reach steady-state concentrations in soil rather than building up over time, with field trials confirming materials continue to degrade and eventually mineralise into carbon dioxide, water, and biomass.
Biodegradable agricultural mulch films, certified under European Standard EN 17033:2018, must convert at least 90% of organic carbon to carbon dioxide within 24 months.
Gail Shuttleworth, the report’s lead author from Alder BioInsights, commented: “In contrast to conventional microplastics, genuinely biodegradable microplastics are transient and will undergo full mineralisation when exposed to the appropriate environmental conditions.
“This fundamental difference makes them a key tool in tackling microplastic pollution from plastics used in, or prone to, entering the open environment.”
The BB-REG-NET report emphasises that while biodegradable plastics are not a complete solution to microplastic pollution, they claim they offer a ‘fundamentally different trajectory’ from conventional plastics.
Biodegradable and compostable materials can significantly reduce long-term persistence of microplastics in the environment with appropriate product design, use, and regulatory oversight, the report says.