German researchers report that they've found arsenic in hundreds of samples of beer, some at levels more than twice of what's allowed in drinking water.
Details of the research, which was discussed Sunday in New Orleans at the 245th National Meeting & Exposition of the American Chemical Society, revealed that the filtering process of beer in Germany is responsible for the slightly elevated levels of arsenic that was discovered.
According to a report by Science Daily, Mehmet Coelhan, PhD, and his team at the Technische Universität in Munich tested 140 samples of beers sold in Germany as part of a monitoring program. The monitoring checked levels of heavy metals like arsenic and lead, as well as natural toxins that can contaminate grain used in brewing beer, pesticides and other undesirable substances.
The team concluded that the arsenic was released into the beer from a filtering material called kieselguhr, or diatomaceous earth, used to remove yeast, hops and other particles and give the beer a crystal-clear appearance.
Diatomaceous earth, also known as D.E. or diatomite, consists of fossilized remains of diatoms, a type of hard-shelled algae that lived millions of years ago. It finds wide use in filtering beer and wine and is an ingredient in other products because the diatom fossils have lots of minute holes. As a result, they do a great job filtering liquids.
"We concluded that kieselguhr may be a significant source of arsenic contamination in beer," Coelhan said. "This conclusion was supported by analysis of kieselguhr samples. These tests revealed that some kieselguhr samples release arsenic.
Coelhan went on to suggest that the resulting arsenic levels were only slightly elevated, and it is not likely that people would get sick from drinking beers made with this filtration method.
The German researcher also reportedly pointed out that beers produced in at least six other countries had higher arsenic amounts than German beers. He said that breweries, wineries and other food processors that use kieselguhr should be aware that the substance can release arsenic.