Pump-underway ship intake: An unexploited opportunity for Marine Strategy Framework Directive (MSFD) microplastic monitoring needs on coastal and oceanic waters

Abstract

Broad scale sampling methods for microplastic monitoring in the open ocean waters remain a challenge in oceanography. A large number of samples is required to understand the distribution, abundance and fate of microplastic particles in the environment. Despite more than a decade of widespread study, there is currently no established time series of microplastic measurements and the research community is yet to establish a standardised set of methods that will allow data to be collected in a quick, affordable and interoperable way. We present a sampling technique involving the connection of a custom-built microplastic sampling device to the pump-underway ship intake system of a research vessel (RV) as an unexploited opportunity for oceanic monitoring needs concerning microplastic abundance and distribution. The method is cost effective, highly versatile and accurate, and is able to sample particles down to 50μm from opportunity platforms, thus contributing to an emerging area of study, and in particular helping to increase the monitoring reporting of data, and thereby serving as a valuable aid for the implementation of the Marine Strategy Framework Directive (MSFD). Sampling was performed during three consecutive oceanographic cruises in the subtropical NE Atlantic over a year, sampling subsurface waters (4 m depth) during navigation and while on coastal and oceanic stations. Microplastic particles were found in all stations and transects sampled. Fibres (64.42%) were predominant over fragments (35.58%), with the concentration values falling within the ranges of data reported for other areas of the Atlantic.

A mixed method assessment of research productivity on microplastics in various compartments in the environment

“…The effects of MPs on the environment and ecosystem depend on the types of polymers involved because they have varied toxicity levels (Montoto-Martínez et al 2020 ). According to Zimmermann et al ( 2019 ), extracts obtained from PVC and PUR were with highest toxicity, while PET and HDPE were either non- or slightly toxic (Esterhuizen and Kim 2022 ).…”

“…Microplastics (MPs) are one of the most prominent emerging contaminants of that have recently risen to the forefront of public concern. They are distributed widely in various compartments of the environment across the world, including freshwater (lake, dam, rivers), seawater (Cole et al 2011 ; Novotna et al 2019 ), raw water supplying some drinking water treatment plants, tap (treated) and bottled water, wastewater, air, soil, sediments, and atmosphere (Mason et al 2018 ; Oßmann et al 2018 ; Pivokonsky et al 2018 ; Schymanski et al 2018 ; Mintenig et al 2019 ; Montoto-Martínez et al 2020 ; Wang et al 2020a , b ). Plastic pollution is one of the major global health environmental challenges, owing to its ecological and health consequences, especially for humans (Chae and An 2017 ).…”

“…Regrettably, the marine environment is more impacted by these growing contaminants, and they affect biota in this setting (or location) in different ways (Hartmann et al 2019 ; Seeley et al 2020 ). These set of environmental pollutants constitute not less than 80% of the litter in the sea (Montoto-Martínez et al 2020 ). In 2015, approximately 300 million tons of the 400 million tons of plastics produced ended up as environmental waste because proper disposal methods are lacking (Astner et al 2020 ).…”

“…MPs below 5 mm in size have been considered by the European Commission for the development of standards needed to monitor and evaluate the environmental situation of seawater with respect to plastic pollution (Montoto-Martínez et al 2020 ). Although, this upper boundary of 5 mm has received major acceptability among scientists, however, the lower limit varies from the most generally used 1–20 µm adopted by other researchers (de Witte et al 2014 ; Ryan 2015 ; Van Cauwenberghe et al 2015 ).…”

“…Although not less than 50% of the plastics in the sea are high density (Bui et al 2020 ). The buoyant ones due to their light weights are easily carried from one location to another and, thus, act as vectors/carriers for different species of plants and organisms growing on them, or moving debris all around the aquatic region (Li et al 2020 ; Montoto-Martínez et al 2020 ). MPs are also grouped based on their appearance, shape, or form.…”