[Analysis on transfer rate change of heavy metal in decoction and precipitation of Curcuma phaeocaulis before and after processing with vinegar based on ICP-MS].

Chinese herbs are mostly used to make decoction, which would form precipitation after standing for cooling and abandoned by patients. Processing with vinegar can change the property of the herbal pieces, such as the transfer rate of heavy metal into decoction. To analyze the transfer rate change of heavy metal in the decoction and precipitation of Curcuma phaeocaulis before and after processing with vinegar, inductively coupled plasma mass spectrometry (ICP-MS) was used to establish the determination method on five heavy metals in C. phaeocaulis, including Copper (Cu), arsenic (As), chromium (Cd), lead (Pb), mercury (Hg), using microwave to digest the samples, indium (In) as the internal standard, and national level standard material tea leaves GBW10016 (GSB-7 tea) as the quality control standard material. Then, the content of five heavy metals in the herbal pieces, decoction and five heavy metals of 6 representative batches of C. phaeocaulis and their vinegar-processing products was determinated. After computation, the transfer rates of heavy metals in the decoction and precipitation of C. phaeocaulis Val. before and after the processing with vinegar were obtained. The results showed that, after the processing with vinegar, total transfer rate of Pb and Hg was decreased significantly; total transfer rate of Cd and Cu was slightly decreased; total transfer rate of As was slightly increased, however heavy metals in all the precipitation were decreased. The results indicated that processing with vinegar had certain influence on heavy metal transfer rate, with certain synergistic and attenuated effect.