Lightweight plastic carrier bags continue to be at the center of a debate regarding the role of oxo-degradability in helping to solve the littering and plastic pollution problem that is prevalent globally. A report from the European Commission (EC) to the European Parliament and the Council was released on Jan. 16, 2018. Directive 94/62/EC2 (April 29, 2015), which involved a reduction in the consumption of lightweight plastic carrier bags, contained Article 20a (2), which tasked the EC to present a report to the European Parliament and to the Council on the impact of the use of oxo-degradable plastic carrier bags on the environment and, if appropriate, present a legislative proposal.
A study published in April 2017 addressed three key issues:
- The biodegradability of oxo-degradable plastic in various environments;
- environmental impacts in relation to littering; and
- issues related to recycling.
The results were analyzed to ascertain whether the “claims and assumptions from the oxo-degradable industry” can be supported or refuted. “Oxo-degradable plastics are conventional plastics which include additives to accelerate the fragmentation of the material into very small pieces, triggered by UV radiation or heat exposure,” states the report. “Due to these additives, the plastic fragments over time are reduced into plastic particles, and finally microplastics, with similar properties to microplastics originating from the fragmentation of conventional plastics.”
The question is whether plastic containing an oxo-degradable additive will degrade in “uncontrolled conditions in the open environment . . . or marine environment” [and] will “undergo full biodegradation within a reasonable timeframe.” If the oxo-degradable plastic does not biodegrade within a reasonable timeframe, which the report does not define, will the microplastics released into the environment—including the marine environment—get into the food chain and “end up being consumed by humans?”
But, what is a reasonable timeframe? Over the span of one hundred million years, a reasonable timeframe may be 50 years. Currently, rules for biodegradation require that the plastic, to be labeled as such, must degrade to a certain size within a specified timeframe, generally six months to a year. Material that does not biodegrade within that timeframe cannot be called biodegradable.