This study was carried out to estimate the pelagic microplastics (plastics from size 0.5mm to 5mm, reported in unit of pieces/m^3) concentration in the North Atlantic Ocean. Microplastics data was collected from 2020-11-06 to 2020-11-29 aboard RV Pelagia, using a manta net. This dataset contains the results from all 36 sampling efforts, in a spreadsheet format.

This study estimated the concentration of microplastics (i.e. plastics measuring less than 5mm; reported in unit of items/kg d.w) in subtidal sediments from the Sado River estuary and the Arrábida marine park, Portugal collected from 2018-08-22 to 2019-02-27. Microplastics were collected using a petite Ponar benthic grab. This dataset contains the results from all 36 sediment samples, in a spreadsheet format.

This study estimated the concentration of microplastics (i.e. plastics measuring less than 5mm, reported in unit of pieces/m2) on the beaches of Holbox Island, Mexico from 2018-05-18 to 2018-05-19. Microplastic data were collected using a PVC cylinder. This dataset contains the results from all 40 beach sand samples, in a spreadsheet format.

This study was carried out to estimate the floating microplastics (plastics from size 0.5mm to 5mm, reported in unit of pieces/m^3) concentration in the eastern North Pacific Ocean. Microplastics data was collected from 2015-08-02 to 2019-12-09 aboard MV Maersk Transporter, using a manta net. This dataset contains the results from all 54 sampling efforts, in a spreadsheet format.

The San Francisco Estuary Institute and 5 Gyres completed a comprehensive regional study of microplastic pollution of a major urban estuary and adjacent ocean environment, sampling in stormwater, treated wastewater, surface water, sediment, and prey fish.

This study estimated the abundance of microplastics (i.e., plastics measuring less than 5mm) on marine turtle nesting beaches during 2018-08-04 to 2020-01-24. Samples were collected with metallic trowel. Sand samples were collected from 209 sites spanning six oceans and 39 countries by a global network of marine turtle scientists. Microplastics were extracted through stacked sieves, visually identified, and a sub-sample verified via Fourier-transform infrared spectroscopy. Microplastic particles were counted and weighed, which in combination with the dry sand sample weight and volume, allowed multiple units of measure to be calculated: Plastic weight per kg of dry sediment (g kg-1), plastic particle number per kg of dry sediment (particle kg-1), and plastic particle number per m-3 of dry sediment (particle m-3). Plastic particles were also categorized into five types: industrial plastic pellets, foams, fragments, sheetlike user plastics and threadlike user plastics. This dataset contains the results from all 209 samples in a spreadsheet format.

This dataset describes the quantity and morphology of microplastics in water, surficial sediment, sediment core, fish, and shellfish samples from Lake Mead National Recreation Area (Nevada/Arizona). Water and surficial sediment samples were collected once at 9 locations. A sediment core (33 cm long) was extracted from Las Vegas Bay to assess changes in microplastic deposition over time. Striped bass (Morone saxatilis), common carp (Cyprinus carpio), quagga mussels (Dreissena bugensis), and Asian clams (Corbicula fluminea) were sampled at a subset of locations to assess biological uptake of microplastics. Sampling and analysis methods are described in the Processing Steps section of the metadata. All samples were collected in March 2017 except the sediment core, which was collected in March 2018.