There is no doubt that individual animals occasionally die from entanglement in, or the ingestion of marine plastic debris. But what is the real evidence for the extent of harm from little to large plastic debris on cells, tissues or organs of animals, on their health, reproductive capacity or survival, and finally on the species or animal communities in the ecosystem?
Damage from marine debris is hard to demonstrate
IMARES participated in a review of literature, attempting to separate assumptions or apparent relations from scientifically proven facts on the damage from marine debris. Correlations do not provide solid scientific evidence for cause and effect. Although clear examples of damage were found at all biological levels, the result show how hard it is to really demonstrate the extent of harm or damage from marine debris. The study aims to strengthen future research in terms of properly quantifying harm.
Rochman, C.M., Browne, M.A., Underwood, A.J., Van Franeker, J.A., Thompson, R.C. & Amaral-Zettler, L. 2016. The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived.
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