The debate about microplastics has attracted more than a thousand readers

FRAM’s Centre Director Thomas Backhaus and Associate Professor Martin Wagner have had a debate about microplastics for several months. Thousands of readers have taken part of their arguments, and they have now written their final statements. Should we take the precautionary stance, or the evidence-based approach?

Martin Wagner argues for the first one.
“Based on my values, I favor a precautionary approach to microplastics, not because I consider them doomsday devices but because I believe in positive change. Microplastics and plastic pollution are the best vehicle we have seen in years to communicate environmental and sustainability issues to the public, engage them in discussions on how we want our future to look like and search for solutions jointly.”

Wagner continues with clarifying that we still need better scientific evidence.
“We need to understand the actual sources of microplastics, the processes driving their fate and the properties driving their impacts.”
He also argues that researchers should be able and willing to resist doomsday communication.
“Systemic problems can only be tackled with systemic solutions. /…/ So, here is another large question we need to talk about: How do we make the public conversation about environmental issues sustainable?”

Thomas Backhaus, on the other hand, is an advocate for the evidence-based approach. He starts his final statement with a call for more empirical data on microplastics toxicity to environmental organisms and to humans, which today “remain surprisingly sketchy and almost elusive.”

Backhaus is also clarifying whether microplastics could be equated with PCBs and similar compounds, which is sometimes done today.
“To me this is a false equivalency. First, several PCBs are, in contrast to microplastics, potent endocrine disrupters. Secondly, microplastics do hardly, if at all, bioaccumulate or biomagnify –certainly not to the same extent as PBT/vPvB chemicals. Although studies have managed, after painstaking efforts, to find some microplastic particles embedded in biological tissue and transferred through the food chain, it is still more than a far stretch to equate these particles with PCBs, brominated flame retardants, dioxins and similar compounds, who are found in organisms in concentrations thousands of times higher than in the surrounding environment.”

Backhaus continues with the argument that there are more pressing matters to act upon, than the mere occurrence of microplastics in the environment.
“…microplastic in the environment is an issue certainly worthy of scientific investigation. /…/ But, to me, it is not an issue that warrants political or societal action just right now. Not before we do not have a better understanding of how we could/should act.”

On his own website, Thomas Backhaus concludes that the form of the debate could be useful:
“…the debate shows that preprints are an interesting communication tool that can also take a middle ground between public panel discussions and peer-review papers.”

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