PLASTIC POLLUTION: SCIENTIFIC RESEARCH
Plastic pollution is emerging as a pressing and widespread global environmental concern. The proliferation of microplastic fragments and dust in the environment is altering the natural geomorphological composition of the earth’s surface, as well as its river and marine environments.
The relatively low cost of plastic and rising levels of production have resulted in widespread geographical dispersion and high concentrations in fluvial and marine environments. Recent estimates suggest that even in relatively remote parts of the oceans, concentrations of over 580,000 pieces per km2 are common. At current rates, plastics ingestion by seabirds is predicted to reach 99% of all species by 2050 (Wilcox et al, 2015).
Most plastics polymers do not biodegrade but photodegrade, meaning that it is imperative that they are exposed to sources of either light or heat to degrade fully. These sturdy polymers can also attract high concentrations of harmful hydrophobic contaminants. Calculations for degradation rates vary for different types, but can be anything from twenty to thousands of years. However, plastics tend to fragment and are then spread even further throughout aquatic and terrestrial ecosystems. Ultimately these fragments become toxic plastic dust, impossible to remove from the environment.
The ubiquity of plastic pollution has yet to be recognised in the wider public realm. Through a series of collaborations and public engagements, the project ‘Thames Memory and the Exploration of Future Dust’ seeks to challenge our understanding of plastics and raise awareness of the geographical reach of the problem.
Plastic debris flows through urban river catchments in the same way as sediment, entering river channels via various sources, being transported, stored and eventually reaching the sea.
The Department of Geography at King's College London is leading investigations to characterise and quantify the plastics within the Thames catchment, examining what types, forms and sizes of plastic are most abundant, how they are transported and where they are stored within the fluvial landforms of urban rivers. Knowledge of plastics distribution is important for understanding the plastics budget of urban catchments, in order to best prevent its addition and manage its removal. Ancillary research is focused on breakdown rates and ecological impacts of plastics to further facilitate effective management.