Investigation into Trihalomethanes in Lager Beers Brewed in Ghana

Abstract

Water is a vital ingredient in beer constituting 91-98% of the content. In Ghana, the main source of water for the two major breweries in the city of Accra is from the Ghana Water Company which takes its source from the Weija Dam and the quality of the water, which may be changed without warning. Moreover, chlorination is the most widely used water disinfection process. Trihalomethanes are formed when water containing natural organic matter reacts with chlorine used in disinfection and other halogens. Trihalomethanes are potential carcinogens and it has been reported to cause a higher incidence of bladder and colon cancer in animals. Therefore, this research was carried out to determine the levels of trihalomethanes in six selected brands commercially brewed lager beers by the two major breweries in Ghana. A gas chromatograph equipped with an electron capture detector coupled with a headspace auto-sampler fitted with the column HP-5, 30m × 0.32mm × 0.25µm was used in analyzing fourty-eight bottles of lager beers comprising of 8 different batches from each of the six brands. The highest trihalomethane detected in the lager beers was chloroform with a concentration 20.19 ±  2.73µg/l and the least detected was dibromochloromethane of concentration 0.282 ± 0.06µg/l. The levels detected were below the World Health Organization’s total daily intake guideline values of 300µg/l, 60µg/l, 100µg/l and 100µg/l for chloroform, bromodichloromethane, dibromochloromethane and bromoform respectively in drinking water. However, regular intake of beer with higher concentrations of trihalomethanes as it was observed in some of the samples can increase the risk of one being diagnosed of cancer related ailments in the longer future. It is therefore recommended that the regulatory bodies such as the Food and Drugs Authority (FDA) and the Ghana Standards Authority (GSA) must begin to monitor the levels of trihalomethanes in beers and other beverages that are produced in the country to help safeguard the health of the citizenry.

Keywords: Trihalomethanes , carcinogens, chlorination, gas chromatograph, lager beers