Analysis of the Floating Marine Litter that Flows out of Japan as Observed from Beach Litter

Abstract

The amount of litter found washed ashore on the beach from different countries is considered to be a good indicator of any particular countryʼs solid waste management situation. In a survey, the largest amounts of litter found washed up on the beaches of Tottori Prefecture in Japan were fishing tools from other places. The total quantity of these kinds of waste materials, e. g. ropes, floats and 20 liter-plastic containers) measured in at 65 kg/(hm・y), whereas wastes ascertained to actually originate in Japan were much less. The second largest amount of litter found was waste from consumer goods. The total amount of beverage bottles, detergent and seasoning packets, gas cartridges, spray cans and disposable lighters measured in at approximately 28 kg/(hm・y), of which about half was estimated to originate from Japan. The total quantity for agricultural chemical bottles and fertilizer bags from Japan weighed about 0.8 kg/(hm・y), though the bags easily sink when drifting so do not always make it onto the beach. The most alarming quantities of beached wastes originating from Japan were that of beverage bottles. These wastes are often dumped inland near riversides and also around beaches during the summer season. The quantities of waste washed ashore from these two sources were estimated using multiple regression analysis, inputting the numbers for large plastic (PET) bottles and pull-tab drink cans as the descriptive variables.