Investigation into Benzene, Trihalomethanes and Formaldehyde in Chinese Lager Beers

Beers brewed commercially in China have been surveyed for the presence of a number of potential contaminants, including benzene, trihalomethanes and formaldehyde. Of 84 beers only 6 contained detectable benzene, at concentrations ranging from 1.9 to 7.1 μg/L (mean of 4.0 μg/L). Further investigations suggested that the source of the benzene could be the carbon dioxide used for carbonation. Trihalomethanes were measured in 107 beers (consisting of 27 Chinese brands) by headspace gas chromatograph with average and maximum concentrations of 1.2 μg/L and 5.2 μg/L respectively. Total trihalomethanes were also measured in water samples from different brewing sites. Concentrations varied from 2.7–46.9 μg/L, except for one sample which contained 79.3 μg/L. Formaldehyde was measured in 29 beers (including 7 imported brands) using solid-phase microextraction with on-fiber derivatization. Formaldehyde levels were between 0.082-0.356 mg/L. None of the beer samples exceeded WHO drinking water criteria for benzene, trihalomethanes or formaldehyde.