Distribution range of disposable lighters collected on the river bank

Abstract

The method used to estimate marine litter sources by indicator items with the information of outflow location has some errors because of the existing mismatch of the distribution and disposal location. In this study, 3,472 lighters were collected on the river banks off our major rivers（Arakawa, Tamagawa, Yodogawa and Sendai）from November 2003 to November 2012, because the lighters collected from the river do not have errors which was disposed on the sea and transferred from the distribution location to far. Outflow ranges were estimated using one-sided confidence interval of average of the liner distance from the distribution point（shop address printed on the side of lighter tank） to the collected point. These outflow ranges were estimated with in the distance of 80～160 km range from the river mouth.