The Complex Interaction between Marine Debris and Toxic Chemicals in the Ocean

Abstract

Marine debris, especially plastic debris, is widely recognized as a global environmental problem. There has been substantial research on the impacts of plastic marine debris, such as entanglement and ingestion. These impacts are largely due to the physical presence of plastic debris. In recent years there has been an increasing focus on the impacts of toxic chemicals as they relate to plastic debris. Some plastic debris acts as a source of toxic chemicals: substances that were added to the plastic during manufacturing leach from plastic debris. Plastic debris also acts as a sink for toxic chemicals. Plastic sorbs persistent, bioaccumulative, and toxic substances (PBTs), such as polychlorinated biphenyls (PCBs) and dioxins, from the water or sediment. These PBTs may desorb when the plastic is ingested by any of a variety of marine species. This broad look at the current research suggests that while there is significant uncertainty and complexity in the kinetics and thermodynamics of the interaction, plastic debris appears to act as a vector transferring PBTs from the water to the food web, increasing risk throughout the marine food web, including humans. Because of the extremely long lifetime of plastic and PBTs in the ocean, prevention strategies are vital to minimizing these risks.

Global Distribution, Composition and Abundance of Marine Litter

“…Deep-sea surveys are important because ca. 50 % of plastic litter items sink to the seafloor and even low-density polymers such as polyethylene and propylene may lose buoyancy under the weight of fouling (Engler 2012). While acoustic approaches do not enable discrimination of different types of debris on the seafloor except for metals and may not record smaller objects, trawling was considered the most adequate method when taking into account mesh sizes and net opening width (Galgani et al 2011b) (Fig.…”

Focal plane array detector-based micro-Fourier-transform infrared imaging for the analysis of microplastics in environmental samples

“…Another more alarming aspect is that microplastics can release toxic additives and they are known to accumulate persistent organic pollutants (POPs). [32][33][34][35][36] Hence, when microplastics, because of their minuteness, enter marine food webs at low trophic levels they simultaneously harbour the risk of potentially propagating these toxic substances up the food chain. [37,38] This issue is discussed controversially in recent research and although several studies suggest it being of minor importance from a risk assessment perspective [39,40] microplastics have the potential to transport POPs to human food.…”

“…[37,38] This issue is discussed controversially in recent research and although several studies suggest it being of minor importance from a risk assessment perspective [39,40] microplastics have the potential to transport POPs to human food. [33] In addition, because of their material properties many microplastic particles are buoyant and their durability enables them to travel long distances. [41] They can thus function as vectors for the dispersal of toxic or pathogenic microorganisms.…”

Contaminant release from aged microplastic

“…It is expected that microplastics release more potentially harmful compounds than bulk plastics, owing to the shorter diffusion path length from the bulk material to the surface. During further fragmentation, new surfaces are created and the particles can be seen as a long-term source of potentially toxic compounds [17] . Ecotoxicity is determined rather by this bioavailable fraction than by the total amount.…”