Research indicate that marine plastic is subjected to processing releases chemicals that attract aquatic birds and potentiate damage:
Read more at:
M. Savoca et al. Marine plastic debris emits a keystone infochemical for olfactory foraging seabirds. Science Advances. Published online November 9, 2016. doi: 10.1126/sciadv.1600395.
H. Thompson. Tiny plastics cause big problems for perch, lab study finds. Science News. June 25, 2016.