M.H. Depledge, F. Galgani, C. Panti, I. Caliani, S. Casini, M.C. Fossi, 
Plastic litter in the sea, Marine Environmental Research, Volume 92, 
December 2013, Pages 279-281, ISSN 0141-1136, 
http://dx.doi.org/10.1016/j.marenvres.2013.10.002.
(http://www.sciencedirect.com/science/article/pii/S0141113613001736)
Abstract: On June 2013 a workshop at the University of Siena (Italy) was 
organized to review current knowledge and to clarify what is known, and 
what remains to be investigated, concerning plastic litter in the sea. 
The content of the workshop was designed to contribute further to the 
European Marine Strategy Framework Directive (MSFD) following an 
inaugural workshop in 2012. Here we report a number of statements 
relevant to policymakers and scientists that was overwhelming agreement 
from the participants. Many might view this as already providing 
sufficient grounds for policy action. At the very least, this early 
warning of the problems that lie ahead should be taken seriously, and 
serve as a stimulus for further research.