How much may German beers be contaminated by microplastics?

The research, published this month in Food Additives and Contaminants: Part A, analysed 24 beer samples from local supermarkets and included both alcoholic and non-alcoholic beer. Contamination was found in all cases. Defining microplastics as 'fibres, films, fragments or granular particles smaller than 5 mm in size and made of synthetic polymers', the authors found that regular tap water may also be subject to this contamination.

Though contamination was found in all instances, it was not possible to establish any one microplastic as being more dominant than the others. Indeed, the contributions ranged from 5% to 71% for granular material, from 14% to 87% for fragments and from 3% to 57% for fibres and varied depending on the brand of the beer.

The study also indicated that the contamination wasn't just caused by microplastics, indeed one beer sample even contained an almost complete insect belonging to the Order Thysanoptera. Moreover, three samples revealed glass shards of up to about 600 μm size.

The authors of the article, Gerd Liebezeit & Elisabeth Liebezeit, conclude their research by suggesting possible causes for the contamination, citing the materials used in the production process and the clothes and skin of brewery workers as likely sources.