A recent study from Australia, the findings of which are based on a flawed premise that PVC is a common ocean plastic, has lured certain national media outlets to promote its reckless and inaccurate claim that PVC dangerously affects phytoplankton productivity in our oceans. These allegations are wildly misleading – and the media outlets that cover them do a great disservice by perpetuating unreliable information to unwitting readers and viewers.
Specifically, the study’s authors erroneously make a key assumption on a material that is not commonly found in our oceans. They draw irresponsible conclusions that are impossible to replicate in a real-world ocean environment. And they fail to use a level of scientific rigor that is anything close to the gold standard.
First, the study suggests PVC is a common material in our oceans – and that simply isn’t true. Of all of the plastic found in the world’s waste stream, just 2.8% is PVC according to the United Nations. And, there is no reason to believe that PVC would end up in the ocean at all, since it would be less likely to float on the rivers that carry plastic waste to the ocean in the first place. The study bases its conclusions on the false premise that PVC makes up a large portion of the plastic in our oceans – any such claim is categorically false.
Not only were typical ocean plastics not tested, but only two plastic items were also selected and tested, by the investigators. The authors went to a local shop, bought a flexible PVC mat, carried it in a plastic bag, cut them both into pieces, immersed them into artificially created ocean water, and conducted testing to draw their results. They made a claim about an entire category of materials based on this hyper-selective and narrowly-focused approach, without any consideration for why the sample was selected, and how it would apply to the projected conclusion that an average reader would take away. For these reasons, the study cannot be trusted.
The study falsely suggests that PVC is a major contributor to the destruction of our marine ecology. The results of the study determined that zinc is the primary harmful contaminant identified. While it is used as an additive in some vinyl products, zinc is a far more common element in countless materials and products specifically used in or around our shorelines, including fencing, metal piping, steel ships, and notably, sunscreen. Furthermore, over 35,000 tonnes per year of zinc come from volcanic releases into the environment. Based on the study’s findings, to suggest that PVC could have a major influence on our oceans is wildly irresponsible.
The outlet that published the flawed research did not appear to follow established NIH’s guidelines in assessing the study’s credibility. The publication, Communications Biology, even acknowledges on its website that its mission is to deliver the “rapid dissemination of results” – which stands in direct contradiction to its aspirational claim to be a source of “high quality” research. The National Institutes of Health (NIH) specifies the comprehensive review process studies must undergo in order to be deemed credible. Readers are right to question whether Communications Biology followed these guidelines, as any outlet that prioritizes speed-of-delivery of the research they publish is likely to fall well short of the NIH’s high standards.
Readers deserve to know when scientifically sound studies raise legitimate public health and environmental concerns. Society also deserves to have information from reliable sources that collaborate and engage with stakeholders to ensure the highest quality outcomes, and to anticipate future research needs. They don’t deserve to be exposed to unreliable, uncorroborated research that only sparks baseless public fear.