A method was developed for the determination of trace lead in traditional Chinese medicine Rhaponticum uniflorum by graphite furnace atomic absorption spectrometry(GFAAS),using diammonium phosphate as chemical modifier.The effects of chemical modifiers,ashing temperature,atomization temperature and common coxeisting components on the determination of lead were investigated.Under the optimized operating conditions,the detection limits of this method was 0 61 ng/ml with precision of 4 0%.The recoveries of standard addition were 94% 103%.
