METRICS Some altmetrics are too easy to game so lack credibility p.176 THEATRE New York play explores why Isaac Newton stuck a needle in his eye p.175 ECODESIGN Materials makers on how to do more with less p.174 ECODESIGN Olympic velodrome engineer builds with nature p.172 Classify plastic waste as hazardousPolicies for managing plastic debris are outdated and threaten the health of people and wildlife, say Chelsea M. Rochman, Mark Anthony Browne and colleagues.

Samples of polyethylene pellets were collected at 30 beaches from 17 countries and analyzed for organochlorine compounds. PCB concentrations in the pellets were highest on US coasts, followed by western Europe and Japan, and were lower in tropical Asia, southern Africa and Australia. This spatial pattern reflected regional differences in the usage of PCBs and was positively correlated with data from Mussel Watch, another monitoring approach. DDTs showed high concentrations on the US west coast and in Vietnam. In Vietnam, DDT was predominant over its metabolites (DDE and DDD), suggesting the principal source may be current usage of the pesticide for malaria control. High concentrations of pesticide HCHs were detected in the pellets from southern Africa, suggesting current usage of the pesticides in southern Africa. This study demonstrates the utility and feasibility of the International Pellet Watch approach to monitor POPs at a global scale.

Sediment organic matter heterogeneity in sediments is shown to impact the sorption behavior of contaminants. We investigated the sorptive properties as well as the composition of organic matter in different subsamples (mainly grain size fractions) of the Canadian River Alluvium (CRA). Organic petrography was used as a new tool to describe and characterize the organic matter in the subsamples. The samples studied contained many different types of organic matter including bituminous coal particles. Differences in sorption behavior were explained based on these various types of organic matter. Subsamples containing predominately coaly, particulate organic matter showed the highest K oc , the highest nonlinearity of sorption isotherms and the slowest sorption kinetics. Soil subsamples with organic matter present as organic coatings around the quartz grains evidenced the lowest K oc , the most linear sorption isotherms and the fastest sorption kinetics, which was not limited by slow intraparticle diffusion. Due to the high sorption capacity of the coaly particles even when it is present as only a small fraction of the composite organic content (<3%) causes K oc values which are much higher than expected for soil organic matter (e.g. K oc -K ow relationships). The results show that the identification and quantification of the coaly particles within a sediment or soil sample is a prerequisite in order to understand or predict sorption behavior of organic pollutants.

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