J.P.G.L. Frias, V. Otero, P. Sobral, Evidence of microplastics in 
samples of zooplankton from Portuguese coastal waters, Marine 
Environmental Research, Available online 13 January 2014, ISSN 
0141-1136, http://dx.doi.org/10.1016/j.marenvres.2014.01.001.
(http://www.sciencedirect.com/science/article/pii/S0141113614000099)
Abstract: Records of high concentrations of plastic and microplastic 
marine debris floating in the ocean have led to investigate the presence 
of microplastics in samples of zooplankton from Portuguese coastal 
waters. Zooplankton samples collected at four offshore sites, in surveys 
conducted between 2002 and 2008, with three different sampling methods, 
were used in this preliminary study. A total of 152 samples were 
processed and microplastics were identified in 93 of them, corresponding 
to 61% of the total. Costa Vicentina, followed by Lisboa, were the 
regions with higher microplastic concentrations (0.036 and 0.033 no. 
m-3) and abundances (0.07 and 0.06 cm3 m-3), respectively. Microplastic: 
zooplankton ratios were also higher in these two regions, which is 
probably related to the proximity of densely populated areas and inputs 
from the Tejo and Sado river estuaries. Microplastics polymers were 
identified using Micro Fourier Transformed Infrared Spectroscopy 
(μ-FTIR), as polyethylene (PE), polypropylene (PP) and polyacrylates 
(PA). The present work is the first report on the composition of 
microplastic particles collected with plankton nets in Portuguese 
coastal waters. Plankton surveys from regular monitoring campaigns 
conducted worldwide may be used to monitor plastic particles in the 
oceans and constitute an important and low cost tool to address marine 
litter within the scope of the Marine Strategy Framework Directive 
(2008/56/EC).
Keywords: Microplastics; plastic; zooplankton; MSFD; FTIR; Portugal