The degradation of plastic litter in rivers: implications for beaches -
process suggesting photodegradation as the principal cause of sample deterioration. It was not possible to predict lifetimes for plastics in rivers from the test results as they could not realistically be subjected to abrasive actions that would have been encountered dur- ing transportation. Similarly, it is very difficult to test plastic sheeting fragmentation on beaches. In the light of recent complaints and subsequent research regarding plastic sheeting accumulation in the Bristol Channel estuary (Williams et al. 1993b) the potential for riverine contributions to this problem remains high. Very little work has been carried out with regard to this litter source but it is postulated that in ‘flashy’ river areas e.g. the Mediterranean, much beach plastic litter originates from rivers.
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