Plastics in the Marine Environment

Abstract

Plastics contamination in the marine environment was first reported nearly 50 years ago, less than two decades after the rise of commercial plastics production, when less than 50 million metric tons were produced per year. In 2014, global plastics production surpassed 300 million metric tons per year. Plastic debris has been detected worldwide in all major marine habitats, in sizes from microns to meters. In response, concerns about risks to marine wildlife upon exposure to the varied forms of plastic debris have increased, stimulating new research into the extent and consequences of plastics contamination in the marine environment. Here, I present a framework to evaluate the current understanding of the sources, distribution, fate, and impacts of marine plastics. Despite remaining knowledge gaps in mass budgeting and challenges in investigating ecological impacts, the increasing evidence of the ubiquity of plastics contamination in the marine environment, the continued rapid growth in plastics production, and the evidence-albeit limited-of demonstrated impacts to marine wildlife support immediate implementation of source-reducing measures to decrease the potential risks of plastics in the marine ecosystem.

Distribution and Modeled Transport of Plastic Pollution in the Great Lakes, the World's Largest Freshwater Resource

“…Previous surveys of Great Lakes plastic have found a 40-and 6-fold difference between the smallest and largest size classes (Eriksen et al, 2013;Mason et al, 2016). It is likely that the order of magnitude increase in the relative abundance of the smallest size class between previous Great Lakes surveys and the overall maximum abundance in our study can be attributed to our use of a 106 µm size mesh collection net, as opposed to the 333 µm mesh used previously in the Great Lakes and their tributaries (Eriksen et al, 2013;Baldwin et al, 2016;Mason et al, 2016) and in most aquatic plastic debris surveys to date (Hidalgo Ruz et al, 2012;Law, 2016). As a result, our data more comprehensively capture the "micro" plastic range in the Great Lakes, knowledge of which is critical to our assessments of environmental risk.…”

“…As the largest freshwater system on the planet, these critical lakes hold 20% of the world's fresh water. Plastic pollution was documented down to the smallest size class yet reported, shedding light on the magnitude of plastics in a small size class (106-333 µm) that is missing from most existing reports (Hidalgo Ruz et al, 2012;Law, 2016). This led to load estimates of nearly 2 million particles km −2 , the highest reported levels in the Great Lakes and possibly any surface water ecosystem.…”

“…Though recommendations (Ryan et al, 2009) and protocols (Masura et al, 2015) have been put forth for sample collection, processing, and quantification, standardized sampling methodology, and reporting are critically lacking (Hidalgo Ruz et al, 2012;Law, 2016). The reasons for these inconsistencies are multifaceted.…”

“…While most studies rely on visual inspection alone (reviewed in Hidalgo Ruz et al, 2012;Law, 2016), such human sensorybased observations can be error-prone. First, misidentification can occur due to the similarities in appearances of plastic and non-plastic particles (Filella, 2015).…”

“…In recent years, anthropogenic litter in the form of plastic debris has been documented in widespread and diverse marine (Law et al, 2010(Law et al, , 2014Cózar et al, 2014;Fischer et al, 2015;van Sebille et al, 2015;Law, 2016), freshwater (Eriksen et al, 2013;Free et al, 2014;Mani et al, 2015;Baldwin et al, 2016;Mason et al, 2016), and even aeolian (Dris et al, 2015) biomes. It is estimated that 4.8-12.7 million tons of plastic enters the ocean in a single year (Jambeck et al, 2015), with a quarter of a million tons currently floating in the world's oceans .…”