| Abstract
| - Plastic resin pellets (small granules 0.1−0.5 centimetersin diameter) are widely distributed in the ocean all over theworld. They are an industrial raw material for the plasticindustry and are unintentionally released to the environmentboth during manufacturing and transport. They aresometimes ingested by seabirds and other marine organisms,and their adverse effects on organisms are a concern.In the present study, PCBs, DDE, and nonylphenols (NP)were detected in polypropylene (PP) resin pellets collectedfrom four Japanese coasts. Concentrations of PCBs (4−117 ng/g), DDE (0.16−3.1 ng/g), and NP (0.13−16 μg/g) variedamong the sampling sites. These concentrations werecomparable to those for suspended particles and bottomsediments collected from the same area as the pellets. Fieldadsorption experiments using PP virgin pellets demonstratedsignificant and steady increase in PCBs and DDEconcentrations throughout the six-day experiment,indicating that the source of PCBs and DDE is ambientseawater and that adsorption to pellet surfaces isthe mechanism of enrichment. The major source of NP inthe marine PP resin pellets was thought to be plasticadditives and/or their degradation products. Comparisonof PCBs and DDE concentrations in marine PP resin pelletswith those in seawater suggests their high degree ofaccumulation (apparent adsorption coefficient: 105−106).The high accumulation potential suggests that plastic resinpellets serve as both a transport medium and a potentialsource of toxic chemicals in the marine environment.
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