The Complex Mixture, Fate and Toxicity of Chemicals Associated with Plastic Debris in the Marine Environment

Abstract

For decades we have learned about the physical hazards associated with plastic debris in the marine environment, but recently we are beginning to realize the chemical hazards. Assessing hazards associated with plastic in aquatic habitats is not simple, and requires knowledge regarding organisms that may be exposed, the exposure concentrations, the types of polymers comprising the debris, the length of time the debris was present in the aquatic environment (affecting the size, shape and fouling) and the locations and transport of the debris during that time period. Marine plastic debris is associated with a 'cocktail of chemicals', including chemicals added or produced during manufacturing and those present in the marine environment that accumulate onto the debris from surrounding seawater. This raises concerns regarding: (i) the complex mixture of chemical substances associated with marine plastic debris, (ii) the environmental fate of these chemicals to and from plastics in our oceans and (iii) how this mixture affects wildlife, as hundreds of species ingest this material in nature. The focus of this chapter is on the mixture of chemicals associated with marine plastic debris. Specifically, this chapter discusses the diversity of chemical ingredients, byproducts of manufacturing and sorbed chemical contaminants from the marine environment among plastic types, the role of marine plastic debris as a novel medium for environmental partitioning of chemical contaminants in the ocean and the toxic effects that may result from plastic debris in marine animals.

Plastics in the Marine Environment

“…Rochman et al (2016) conducted a critical and systematic review of published literature on the perceived, tested, and demonstrated impacts of anthropogenic debris (all materials in all environments) as a function of debris size and affected level of biological organization (i.e., assemblage, population, organism, and suborganism levels; note that the construct did not account for some behavioral or physiological responses, such as altered feeding, movement, or growth). A comprehensive review of the literature on encounters with and biological impacts of plastic marine debris is beyond the scope of this article, and I refer readers to several recent reviews for more detail (Gall & Thompson 2015, Kiessling et al 2015, Kühn et al 2015, Lusher 2015, Rochman 2015, Rochman et al 2016). Here, I present an overview of the types of encounters documented between marine organisms and plastic debris and the potential and demonstrated impacts of such encounters to convey the state of understanding, including major gaps that require further research.…”

“…Many of these substances are known to be persistent, bioaccumulative, and toxic (PBT), with at least 78% of the priority pollutants identified by the US EPA known to be associated with plastic marine debris (Rochman et al 2013a). PBT substances are typically hydrophobic and therefore readily sorb out of seawater onto other hydrophobic substances, such as sediment, organic matter, and now plastic (Rochman 2015). In fact, because of their strong attraction to PBT substances, some plastics are utilized as passive sampling devices to measure chemical contaminants in a variety of environmental matrices (Lohmann 2012).…”

“…The sorption of chemicals from seawater to plastic particles has been clearly demonstrated (e.g., Ogata et al 2009, Hirai et al 2011, Rochman et al 2013b, and the rate and extent of accumulation depend on the polymer type, the physical and chemical properties of the plastic (especially those resulting from weathering and biofilm formation), the particle surface area, and the chemical exposure throughout the particle's drift history (Rochman 2015). Because weathering and biofouling processes continually alter the particle surface in ways that increase the affinity for…”

“…chemical sorption, it has been hypothesized that the accumulation of chemicals onto plastic debris will increase with time in seawater, potentially rendering them more hazardous to animals that ingest the debris (Rochman 2015). The risk to marine organisms from ingestion of plastic debris with chemical contaminants is presently an area of primary research (for detailed reviews, see Koelmans 2015 andRochman 2015).…”

The Economics of Marine Litter

“…through ingested plastics or contamination with persistent organic pollutants, POPs). The body of literature describing the contamination of commercially exploited fish and shellfish by microplastic ingestion is growing rapidly, as is the literature analysing the consequences of this contamination on the health of individuals and populations (Galloway 2015;Lusher 2015;Rochman 2015). However, as yet there have been no economic assessments to estimate the costs of these impacts.…”