Determination of trace lead in beer by cloud point extraction-flame absorption spectrometry

A new method for determination of trace lead in beer by flame atomic absorption spectrometry combined with cloud point extraction was developed. The cloud point extraction system was based on TritonX-100 as surfactant and Dithizone as complexing agent. The parameters affecting cloud point extraction, including pH, extraction temperature and time, dosage of extraction agent and complexing agent were investigated and optimized. Under the optimum conditions, a good linearity was observed for lead in the range of 100 ～ 800μg/L with the detection limit of 3. 25μg/L. The recovery was in the range of 95. 9% ～ 98. 7%. The method was rapid, accurate, simple and was applied to the determination of lead in beer.