In coastal areas, the distribution density of plastic bags, plastic bottles, food packaging materials, etc., which are derived from daily life, tends to be higher in the sea areas closer to urban areas where the population density is high. On the other hand, in the offshore area, the density of foamed styrol and other uncategorized plastics was high. The average distribution density of microplastics in the offshore area were higher than that in the coastal area. The proportion of plastic products was high in the benthic litters with as floating litters, but the proportion of fishing gear including fishing nets in the benthic litters was higher than that in the floating litters. This tendency was strong in the sea areas where the fisheries and aquacultures were active.
