The samples correspond to Manta nets and to sample of surrounding water made on October 21, 2015 and December 9, 2015, in two sites of the bay of Brest (France): one close to the recreational marina corresponding to an area subject to strong anthropogenic activities, and the second in the center of the bay characterized by the existence of a temporary vortex created by the tidal surface current concentrating floating debris from the north and south of the bay (Frère et al., 2017). For each sample, the particles were analyzed by Raman spectroscopy to discriminate the type of polymer and the size (Frère, 2017). Microplastics were pooled according to area and sampling time, identified polymer (polyethylene (PE), polypropylene (PP) and polystyrene (PS)) and size (0.3-1 vs. 1-2 vs. 2-5mm), giving a total of 47 microplastic samples and 12 filtered seawater samples that were studied for bacterial communities by 16S amplicon next generation sequencing.

Figure: Cladogram of LEfSe results according to sample types (microplastics and seawater) for samples collected in October 2015 in the bay of Brest, France. The bacterial genus Litoreibacter and Vibrio appear as biomarkers of collected microplastics (Frère, 2017).

Reference:

Laura Frère (2017) Are microplastics a threat in the Bay of Brest (France)? Thesis of the University of Western Brittany, 301pp.

Frère L, Paul-Pont I, Rinnert E, Jaffré J, Petton S, Bihannic I, Soudant P, Lambert C, Huvet A (2017) Influence of environmental and anthropogenic factors on the composition, concentration and spatial distribution of microplastics: a case study of the Bay of Brest (Brittany, France). Environmental Pollution 225, 211-222.

Frère L, Paul-Pont I, Moreau J, Soudant P, Lambert C, Huvet A, Rinnert E (2016) A semi-automated Raman micro-spectroscopy method for morphological and chemical characterizations of microplastic litter. Marine Pollution Bulletin 113, 461-468.

Funding:

This work was supported by the ANR CESA (ANR-15-CE34-0006-02, NANOPLASTICS project) and by the Unique Inter-ministerial Fund (FUI) and the local communities (CR Bretagne, CR PACA, CD29, CATPM and Brest Métropole) as part of the MICROPLASTIC2 project. Frère was funded by a French doctoral research grant (DDP150097 ARED-FRERE) from Brest Métropole (50%) and University of Brest (50%) employed in the Laboratoire des Sciences de l’Environnement Marin (LEMAR), UMR 6539 CNRS/UBO/IRD/IFREMER, 29280 Plouzané, France.