Distribution of foreign mineral materials and heavy metals contained in herbal medicines, and effect of washing

This study was conducted to investigate the content of foreign mineral materials and heavy metals (Pb, As, Cd, Hg) contained in commercial herbal medicines (1504 samples) classified by parts used, and the effect of removing heavy metals by washing treatment (take 50 g of the sample and put 1000 ml of distilled water, shake it gentle by hand for 1 min). The 5% trimmed means of acid-insoluble ash value (%) were as follows; above ground parts (0.76) and underground parts (0.52). Those of the total amount of individual heavy metals value (mg/kg) were as follows; caulis (1.33), flos (1.23), herba (0.91), cortex (0.76), rhizoma (0.73), radix (0.67), semen (0.44) and fructus (0.39). Acid-insoluble ash content was correlated with Pb in herbal medicines of underground parts (r=0.446) (p<0.01). After washing, the removal rate of heavy metals contained in 6 radix herbal medicines shows 33-13% respectively.