Microplastics are a contaminant of global concern and, as such, there has been a rush to action and publication . Over the past decade, this haste has resulted in a chaotic and cluttered literature that is rife with
inappropriate methodologies, unrealistic experimental protocols, misinterpreted results, and overstated significance. A comprehensive critical assessment of the current literature on interactions between particle-feeding molluscs and microplastics and their purported impacts (> 600 publications ) is underway. It is not surprising that microplastics have been noted in shellfish guts globally. What is surprising is the extremely low level of particles routinely recorded (see Table 1 and references therein). The data to date clearly demonstrate extremely low numbers of microplastics in bivalve molluscs globally. There are no unequivocal data demonstrating that their presence in filter-feeding bivalve molluscs is a serious risk to human health and few data to demonstrate negative impacts on the shellfish. Many studies on suspension-feeding bivalve molluscs and other invertebrates are weak. There is a recurring presence in the published literature of misunderstanding of the feeding processes, capabilities for particle selection and rejection, and species-specific differences that all leads to misinformation, misinterpretation, and incorrect assumptions regarding potential impacts. There are major shortcomings to many laboratory studies that examined uptake and accumulation of microplastics by bivalves and their subsequent effects. In most cases, the issues can be traced to poor experimental procedures and animal husbandry, and lack of knowledge of the literature. They are
compounded by a misunderstanding of the basic biology and physiology of molluscs. The shortcomings have led to a seriously
flawed literature based up on the interactions and impacts of microplastic on these animals. Bivalves and other particle-feeding molluscs are complex living organisms with extraordinary capabilities for the control of selective capture, ingestion, and egestion of particulate material. They should be recognized and treated as such in any attempt to describe impacts of stressors, including different particle types, on their feeding and ability to accumulate materials. Any future experimental studies need to be focused carefully, based upon clear questions, use standardized analytical procedures, demonstrate a knowledge of the animals being studied, and an understanding of the literature extant. The hype needs to be curtailed and scientists should not imply impacts or potential impacts when there are no data to support the suppositions. Editors of scientific journals must make a stronger effort to engage qualified peer-reviewers and stop the flow of poorly done studies and superficial reviews that do nothing more than confuse the literature and reinforce prior inadequate studies and potential reviews. Much of this review is excoriating and that is by design – the current state of the science and literature demands it.