TY - JOUR
T1 - Are we underestimating microplastic abundance in the marine environment? A comparison of microplastic capture with nets of different mesh-size
AU - Lindeque, Penelope K.
AU - Cole, Matthew
AU - Coppock, Rachel L.
AU - Lewis, Ceri N.
AU - Miller, Rachael Z.
AU - Watts, Andrew J.R.
AU - Wilson-McNeal, Alice
AU - Wright, Stephanie L.
AU - Galloway, Tamara S.
PY - 2020/10
Y1 - 2020/10
N2 - Microplastic debris is ubiquitous and yet sampling, classifying and enumerating this prolific pollutant in marine waters has proven challenging. Typically, waterborne microplastic sampling is undertaken using nets with a 333 μm mesh, which cannot account for smaller debris. In this study, we provide an estimate of the extent to which microplastic concentrations are underestimated with traditional sampling. Our efforts focus on coastal waters, where microplastics are predicted to have the greatest influence on marine life, on both sides of the North Atlantic Ocean. Microplastic debris was collected via surface trawls using 100, 333 and 500 μm nets. Our findings show that sampling using nets with a 100 μm mesh resulted in the collection of 2.5-fold and 10-fold greater microplastic concentrations compared with using 333 and 500 μm meshes respectively (P < 0.01). Based on the relationship between microplastic concentrations identified and extrapolation of our data using a power law, we estimate that microplastic concentrations could exceed 3700 microplastics m−3 if a net with a 1 μm mesh size is used. We further identified that use of finer nets resulted in the collection of significantly thinner and shorter microplastic fibres (P < 0.05). These results elucidate that estimates of marine microplastic concentrations could currently be underestimated.
AB - Microplastic debris is ubiquitous and yet sampling, classifying and enumerating this prolific pollutant in marine waters has proven challenging. Typically, waterborne microplastic sampling is undertaken using nets with a 333 μm mesh, which cannot account for smaller debris. In this study, we provide an estimate of the extent to which microplastic concentrations are underestimated with traditional sampling. Our efforts focus on coastal waters, where microplastics are predicted to have the greatest influence on marine life, on both sides of the North Atlantic Ocean. Microplastic debris was collected via surface trawls using 100, 333 and 500 μm nets. Our findings show that sampling using nets with a 100 μm mesh resulted in the collection of 2.5-fold and 10-fold greater microplastic concentrations compared with using 333 and 500 μm meshes respectively (P < 0.01). Based on the relationship between microplastic concentrations identified and extrapolation of our data using a power law, we estimate that microplastic concentrations could exceed 3700 microplastics m−3 if a net with a 1 μm mesh size is used. We further identified that use of finer nets resulted in the collection of significantly thinner and shorter microplastic fibres (P < 0.05). These results elucidate that estimates of marine microplastic concentrations could currently be underestimated.
KW - Microplastics
KW - Net
KW - Ocean
KW - Plastic
KW - Pollution
KW - Sampling
UR - http://www.scopus.com/inward/record.url?scp=85086836940&partnerID=8YFLogxK
U2 - 10.1016/j.envpol.2020.114721
DO - 10.1016/j.envpol.2020.114721
M3 - Article
AN - SCOPUS:85086836940
SN - 0269-7491
VL - 265
JO - Environmental Pollution
JF - Environmental Pollution
M1 - 114721
ER -