Plastic fragments

P. W. Fowler. If you make a model with icosahedral symmetry I believe you will find that you will be left with plastic fragments. 

The inability to detect plastic fragments with x-rays will require that each fragment be probed for and wi1i complicate surgical treatment. 

Isolation of micro- and mesoplastics from debris samples that also include biomass is particularly difficult. Floatation (or density-based separation) alone does not completely isolate the plastic fragments from marine debris. Digestion of sample to solubilize and remove the biomass has been suggested acid digestion (Andrady,... 

Graham ER, Thompson JT. Deposit- and suspension-feeding sea cucumbers (Echinodermata) ingest plastic fragments. J Exp Mar Biol Ecol 2009 368 22-29. 

As microplastics move through the environment they can sorb and transport other contaminants. Plastic debris scooped from the ocean has contained polychlorinated biphenyls (PCBs) at concentrations up to 5 parts per million and dichlorodiphenyltrichloroethane (DDT) at approximately 7 PPM, for example [145-147]. Of particular concern are persistent, bioac-cumulative, and toxic (PBT) compounds that would tend to partition into a plastic matrix due to their hydrophobicity the logical inference is fhaf floaf-ing microplastics could transport PBT compounds through the environment and that perhaps the PBT compounds would enter the food chain as organisms ingested fhe plastic fragments. 

Plastic fragments and floating debris can cause fatalities to marine life as a result of ingestion, starvation, suffocation, infection, drowning, and entanglement. Seabirds that feed on the ocean surface are especially prone to ingesting plastic debris that floats. Short-tailed shearwaters... 

An aeraulic facility or equivalent in order to separate the nonbiodegradable plastic fragments. 

Manual separation of clearly distinguishable plastic fragments (if any). 

Heavy fraction no plastic fragments were visible. After drying and chloroform extraction of the whole fraction, the FTIR analysis showed the fingerprint of edible oils and no peaks associated with biodegradable polyesters. 

Dewatered light fraction skimmed off by the BTA Waste Pulper and sampled after dewatering by the screw press here plastic fragments were visible and could be picked up manually. Therefore, the sample was further divided into two subsamples by manual sorting one subsample was comprised of plastic fragments and the other contained residual materials. 

Figure 15.6 Amounts (in wt%), relative to the initial light fraction (after dewatering by the screw press) of the fractions separated after drying, manual sorting of the plastic fragments, chloroform extraction and FTIR...

Part of the process of making plastics evident as a matter of concern may involve bringing citizen scientists into the fold of environmental science in order to study the spatial variation and chemical risks associated with plastics in the environment. In his collaborative project. International Pellet Watch, Shige Takada asks volunteers to collect and return by post pellets and plastic fragments that collect on shores across the world. These microplastics are valuable geographic samples because they can be tested for concentrations of POPs. From these widely gathered and mailed-in pellets. International Pellet Watch has generated maps that document the spread and concentration of... 

International Pellet Watch tells us not only about the pollution status of various POPs and their global distribution, but also about risks associated with chemicals in marine plastics. Because pellets contain POPs, they act as carriers to various species of seabirds, which mistake them for food. However, plastic resin pellets are a minor component of marine plastics debris. The majority of plastics in beach debris are fragments of user plastics, as shown in Figure 11.4 and discussed elsewhere in this book. This plastic debris is also observed floating on the sea surface (Law et al. 2010), and can be ingested by seabirds (Yamashita et al. 2011). These plastic fragments also contain POPs. 

Figure 11.4 Plastic fragments from a beach on Easter Island...

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