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Although microplastics (MPs) are ubiquitous environmental contaminants, little is known about their occurrence and behavior in the terrestrial setting. In this study, MPs have been isolated from soils collected from various geomorphological features (yardangs, sand dunes, moving sands, seasonal lakes) of the Kavir and Lut Deserts on the Iranian plateau. The number of MPs identified in 300 g samples ranged from zero (not detected) in several yardang tops to 25 on some yardang hillsides, with an overall average abundance of about 0.02 MP g–1. The majority of MPs were of a fibrous nature with a size distribution (≤100 μm to ≥1000 μm) skewed toward the lower end, and analysis of a selection of particles by μ-Raman spectroscopy showed that polyethylene terephthalate and Nylon (polyamide) were the principal polymers. Scanning electron microscopy revealed intense degradation of some particles but limited weathering of others. With little evidence of meso- and macroplastics in the deserts, it appears that the majority of MPs are brought into these environments from distant sources via the wind, with smaller, seasonal contributions from runoff associated with the adjacent mountains. It is proposed that some windborne MPs are transported through the deserts relatively rapidly, while others are subject to internal recycling and significant photo-oxidation and mechanical weathering.

Foamed polystyrene (PS) that may be either expanded (EPS) or extruded (XPS) is a rigid, lightweight insulating thermoplastic that has a variety of uses in the consumer, packaging, construction, and marine sectors. The properties of the material also result in waste that is readily generated, dispersed, and fragmented in the environment. This review focuses on foamed PS in the marine setting, including its sources, transport, degradation, acquisition of contaminants, ingestion by animals, and biological impacts arising from the mobilization of chemical additives. In the ocean, foamed PS is subject to wind-assisted transport and fracturing via photolytic degradation. The material may also act as a substrate for rafting organisms while being exposed to elevated concentrations of natural and anthropogenic surface-active chemicals in the sea surface microlayer. In the littoral setting, fragmentation is accentuated by milling in the swash zone and abrasion when beached, with wind transport leading to the temporary burial of significant quantities of material. Ingestion of EPS and XPS has been documented for a variety of marine animals, but principally those that feed at the sea surface or use the material as a habitat. As well as risking injuries due to gastro-intestinal blockage, ingestion of foamed PS exposes animals to harmful chemicals, and of greatest concern in this respect is the presence of the historical, but still recycled, flame-retardant, hexabromocyclododecane. Because foamed PS is particularly difficult to retrieve as a constituent of marine litter, means of reducing its presence and impacts will rely on the elimination of processes that generate foamed waste, modification of current storage and disposal practices, and the development of more durable and sustainable alternatives.

The glass and enameled decorations of bottles of alcoholic beverages sourced from retailers in the U.K. were analyzed by X-ray fluorescence spectrometry for various heavy metals. In the glass substrate, lead, cadmium, and chromium were present at concentrations up to about 1100, 1100, and 3000 μg g–1, respectively, but their environmental and health risks are deemed to be low significance. Of more concern from an environmental and, potentially, occupational exposure perspective are the concentrations and mobilities of Pb and Cd in the enamels of many bottles. Thus, Pb concentrations up to about 100000 μg g–1were found on the décor of various wine bottles and a beer bottle, and Cd concentrations of up to 20000 μg g–1were measured in the decorated regions on a range of spirits, beer, and wine bottles. Moreover, maximum concentrations that leached from enameled glass fragments according to a standard test that simulates water and other liquids percolating through a landfill were about 1200 and 3200 μg L–1for Pb and Cd, respectively, with several fragments exceeding the U.S. Model Toxins in Packaging Legislation and, therefore, defined as “hazardous”. Given that safer decorative alternatives are available and that a precautionary principle should be adopted for toxic heavy metals, the pervasive use of Pb and Cd in the enamels of consumer bottles is brought into question.