Filtering material raised arsenic levels in beer

It all started when some German beers were found to have raised levels of arsenic — more arsenic than was found in the water the brewers were using. So it only made sense that the increased arsenic was coming from something used in the brewing process. The culprit? Filtering material used to remove yeast, hops and other particles.

The findings were announced at the 245th National Meeting & Exposition of the American Chemical Society late last week. Phys.org, a science, research and technology website, reported that Mehmet Coelhan, Ph.D., and colleagues tested 140 samples of beers sold in Germany as part of the program. It was found that a filtering material called kieselguhr, or diatomaceous earth, was the source of the arsenic. From Phys.org:

Diatomaceous earth 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, wine and is an ingredient in other products.

“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. 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 because of the arsenic. The arsenic is still at low levels—the risk of alcohol poisoning is a far more realistic concern, as stated in previous studies on the topic.”

A bit of background, the World Health Organization sets the bar at 10 micrograms of arsenic per liter of water for safe use.

The scientific team hopes these findings will serve as a warning to other brewers, wine makers and food processors that kieselguhr could release arsenic if used. Coelhan stated that kieselguhr alternatives are available and a simple solution could even be washing the kieselguhr before use to remove the arsenic.