Study Claiming Fish Hurt By 'Microplastics' Retracted, 'Remarkable' It Was Accepted

The authors of a high-profile paper about the dangers of fish consuming small particles of plastic say that they will retract their study, after an investigation found them “guilty of scientific dishonesty” and raised the possibility that some of the research described “was not conducted”.

Limnologist Peter Eklöv and marine biologist Oona Lönnstedt, both at Uppsala University in Sweden, continue to strongly defend themselves against allegations made about their work, which was published in Science. But in a statement to Nature’s news team, Eklöv and Lönnstedt said that they have decided to retract the paper.

“Science has to rest on solid ground and the results of this study, even if they are correct, will not be trusted as long as a suspicion of misconduct remains,” they say. “Thus, we decided that we would not have the endurance to keep defending the paper, and hence decided to retract it.” Science says it is in the process of retracting the study.

The controversy centres on a 2016 paper in which the authors reported experiments showing that fish that ate tiny 'microplastics' grew more slowly and were more likely to be eaten by predators.

...In [Sweden’s Central Ethical Review Board's report], the expert panel says that several questions were “repeatedly put” to Eklöv and Lönnstedt about the case, and it found the researchers’ answers to be “in all essentials deficient”, “at times contradictory” and that they often raised further questions.

The paper’s assertion that an animal-ethics committee had approved their specific experiments “is not consistent with the truth”, and by stating that they had approval, the panel says, Eklöv and Lönnstedt have committed scientific dishonesty.

The panel was also concerned about the lack of available original data for the experiments and this contributed to its “scientific dishonesty” finding. Eklöv and Lönnstedt had said last year that a laptop containing the study's data was stolen, and that there had been problems with back-ups. An ‘expression of concern’ was added by Science to the paper last December to note the issue of missing data.

But the fact that the authors “produced no more than weak fragments of the original data and no original traceable data files” also “leads to suspicion that the research was not conducted, at least not to the reported extent”, says the panel.

The report is critical of Science, too. The experiments, as described in the paper, seem to lack adequate control experiments, it says, and “it is remarkable that the article, given these deficiencies, was accepted by the journal Science”. In a statement to Nature's news team, Science said that its reviewers assess both the data presented in manuscripts and whether appropriate controls were done. “If the review process had raised red flags about the controls,” says the statement, “further revision would have been requested by the editors before the paper could be accepted for publication.”