Buerger A, Bates C, Boles C, Vincent M, Dotson S. Ochratoxin A and pesticides in craft beers: A pilot study. Poster presentation P193 at the Society of Toxicology (SOT) Annual Meeting & ToxExpo, San Diego, CA. Toxicologist Late-Breaking Supp. 168(1):63. Abstract 5085. March 2022.
More than 98% of breweries operating in the United States (U.S.) are considered craft breweries, many of which rely on local grains and ingredients for beer production. Authors of published studies have suggested that international craft beers can contain pesticide residues and mycotoxins, such as ochratoxin A (OTA). However, little data exist that examine pesticide and mycotoxin residues in craft beers in the U.S. In this pilot survey, lagers from four regional craft breweries located in the Cincinnati, Ohio metropolitan area and one national domestic lager were purchased in fall of 2020. Samples (N=3 cans/beer, 1 sample/can) were evaluated for presence of OTA through high performance liquid chromatography. In a separate experiment, samples (N=1 can/beer) were assessed for 500 pesticides using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. A search was conducted of U.S., European, and Canadian governmental residue limits for cereals and grains (e.g., hops and barley) and/or exposure limits for OTA and detected pesticides. Measurements of OTA and pesticides were converted to µg/kg bw/day doses using a standard volume of beer intake (2839 mL) and standard human body weight (70 kg). Calculated daily doses of OTA and the two detected pesticides were compared to the identified residue limits and/or exposure limits to calculate margins of safety (MOS). In all five beers (N=3/beer), OTA was <LOD of 0.25 ppb, with resulting MOS values of <0.001. Three of the four craft lagers and the national brand lager did not contain pesticides above the reporting limits; however, one craft lager contained boscalid and dimethomorph at 0.018 and 0.011 ppm, respectively. For boscalid, the identified residue limits in hops and barley ranged from 0.2 to 80 ppm across the US, Canada, and European Union (EU), and for dimethomorph, the identified residue limits ranged from 4 to 80 ppm. The boscalid and dimethomorph MOS in this craft lager ranged from 18 to 3180 and 222 to 4440, respectively. Based on the lack of OTA detected and 498/500 pesticides below the reporting limit in the craft lagers and the national brand lager, as well as the large MOS values for boscalid and dimethomorph, exposure to OTA and these 500 pesticides in the tested beers presents minimal risk to the average beer consumer. Additional studies are needed to verify these findings on a larger scale, and additional considerations may include climate, season, source of grain, and brewing practices