Beer: a magical mixture of hops, barley, and tiny pieces of plastic

By Liz Core
10 September 2014 (Grist) – Plastics are everywhere: on the street, in our refrigerators, all over the oceans — you name it. But now they’re hitting us where it really hurts. Authors of a new study published in the latest edition of Food Additives and Contaminants found traces of plastic particles (and other debris … we’ll get to this later) in beer. This is how the study worked: Researchers lab-tested samples of 24 varieties of German beers, including 10 of the nation’s most popular brands. Through their superpowers of microscopic analysis, the team discovered plastic microfibers in 100 percent of the tested beer samples. Reads the study:

The small numbers of microplastic items in beer in themselves may not be alarming, but their occurrence in a beverage as common as beer indicates that the human environment is contaminated by micro-sized synthetic polymers to a far-reaching extent.

It’s not breaking news that plastics don’t just vanish into the ether when we’re finished with them. Unless you haven’t heard, in which case … BREAKING NEWS: The plastics we use today will stick around longer than your great-great-great-great (and then some) grandchildren. Water bottles and sandwich bags could potentially take up to 500 years to decompose. Here’s why: plastics don’t biodegrade, they photodegrade (or, when exposed to light, disintegrate into a million little pieces). Those pieces stick around for centuries, making their way into any and all ecosystems on the planet — and, apparently, into the amber contents of our steins. [more]

ABSTRACT: A total of 24 German beer brands was analysed for the contents of microplastic fibres, fragments and granular material. In all cases contamination was found. Counts ranged from 2 to 79 fibres L–1, from 12 to 109 fragments L–1 and from 2 to 66 granules L–1. The results show a high variability between individual samples and samples from different production dates. Possible sources of this contamination with foreign materials are discussed. Increasing awareness of the occurrence of plastic contamination in the global environment has lead to increased observation and monitoring (Andrady 2003). Over the last decade the long-term fate of this environmental burden has also received attention, indicating that degradation of larger plastic may lead to the formation of micro-scaled plastic (Thompson, et al., 2004). In the ensuing discussion other sources were also identified such as garments (Browne, et al., 2011), cosmetics such as peelings or tooth pastes, or abrasives used in air blasting. Besides ending up in the waste water stream and via incomplete retention in sewage treatment plants in the natural aquatic environment (Browne, et al., 2011) microplastic fibres may also become airborne from direct input from clothes put out to dry. Also, sewage sludge employed as fertiliser may contain microplastic (Habib, et al., 1998). These may be transferred to the atmosphere by the wind after extended dry periods. Furthermore, agricultural polyethylene foils may become a source of microplastic fragments as these are tailored to disintegrate though the catalytic action of cobalt or other metal salts after a specified exposure time in the environment (Kasirajan & Ngouajio 2012). Microplastic is defined as fibres, films, fragments, or granular particles smaller than 5 mm in size and made of synthetic polymers. A lower limit has so far not been internationally agreed upon, although a large number of studies use 1 μm (cf. Hidalgo-Ruz, et al., 2012). There is presently only limited evidence that microplastic has negative effects on aquatic organisms, either directly by affecting the growth of the first filial generation of a marine zooplankter (Lee, et al., 2013) or indirectly by transferring previously absorbed contaminants to fish (Browne, et al., 2013; Rochman et al. 2013). Effects of microplastics ingested or inhaled by human consumers have until now not been investigated. Particles of synthetic polymers have so far been described to be present in beer only by Hartmann (2006) who noted the presence of polyvinyl polypyrrolidone (PVPP) particles besides glass shards and label residues as well as aluminium particles which were also noted by Steiner et al. (2010). PVPP is used in granular form to clarify and fine beer prior to filtration. This suggests that small particles up to 55 μm in diameter, as found by Hartmann (2006), can pass the units used in beer filtration. We have recently shown that microplastic contamination can be found in honeys (Liebezeit & Liebezeit 2013) and suggested possible pathways by which this contamination may reach the product including atmospheric transport. During this investigation it was found that regular tap water may also contain microparticles. Thus, external sources may contribute to particle loads. In the present communication, we examine beer and show the presence of foreign particles in this product. [more]