Research groups at the University of Tokyo and Tokyo University of Agriculture and Technology have discovered that when microplastic particles, which are a problem in marine pollution, are taken up by mussels, the pattern over time until they are excreted as feces varies depending on the particle size.
In recent years, marine pollution caused by microplastics has become a global problem.A typical marine organism that is specifically affected by this is the mussel (mussel).Widely distributed along the coasts of various parts of the world, it accidentally eats microplastics in water, takes them into the body, is preyed on by fish and shellfish, and is considered to be a microplastic mediator to coastal ecosystems.In addition, because it is a global fishery resource, it may be a route for bringing microplastics into the human body.
This time, we made mussels take in microplastic particles and investigated their effects precisely.Fluorescently labeled polystyrene beads of three sizes (3µm, 1µm, 10µm in diameter) are used as a model for microplastics.As a result, it was found that beads of any size were actively taken up regardless of the size of the beads suspended in the breeding seawater.In addition, it took time for large particles to be excreted as feces, and small particles were quickly excreted.
On the other hand, when comparing the period until no beads were detected in the feces, the smaller the particles, the longer it took.This allows small particles to be expelled mostly quickly, but only a few particles may remain in the body for long periods of time and accumulate, adsorbing more organic pollutants in seawater than larger particles.
It is expected that the physiological effects will be different due to the difference in the retention pattern of particles of different sizes in the body.In the future, it is necessary to pay attention to the particle size in order to clarify the effect of microplastics.
Paper information:[Marine Pollution Bulletin] Size-dependent retention of microplastics in the Mediterranean mussel, Mytilus galloprovincialis
