I have read several literature reviews and studies on the effects of microplastic particles on fish and invertebrates (one example includes the review by Franzellitti et al. (2019)) and there are multiple instances where these particles where found in the nervous system, lymph, and other organs following controlled exposures.
There are also multiple studies that looked at microplastics in marine mammals, but usually they focus on the contents of the gastro-intestinal tract. My question is: how these particles are likely to accumulate in the bodies marine mammals compared to smaller organisms - could the size of the blood vessels of larger whales influence the uptake of microplastics? Some researchers recommend studying this by using marine mammal cell cultures, but I am wondering how well the results of such studies can reproduce what might be happening at a full-body scale. (I study mainly ecology and the behaviour of marine mammals, so my knowledge of differences between various organisms at a cellular level is limited).