Urine and Hair Metal Concentrations in Subjects with Long Term Intake of Herbal Medicine

  • Park Yeong-Chul (Center for Bio-Safety, Catholic University of Daegu) ;
  • Lee Sun-Dong (School of Oriental Medicine, Sangji University) ;
  • Park Hae-Mo (School of Oriental Medicine, Sangji University) ;
  • Kim Jong-Bong (Center for Bio-Safety, Catholic University of Daegu)
  • Published : 2006.03.01

Abstract

One of the main attractions of treatment with herbal medicine is its apparent lack of side effects compared with the drug therapies used in allopathic medicine. However, evidence from various countries suggest that Asian herbal medicine carry a significant risk of contamination with toxic heavy metals at levels that may seriously threaten health. The aims of this study were to analyze and compare concentrations of heavy metals in urine and hair from 184 patients taking herbal medicines in the form of decoctions and/or pills in comparison to 101 control subjects taking either Western or no medications. Levels of metal concentrations exceeding WHO reference values were observed in a number of hair and urine samples for all subjects. After adjusting for potential confounders, taking decoctions or pills was associated with higher levels of some metals (such as Cu, Pb in urine), as well a higher odds ratio of exceeding the upper limit of reference ranges for Pb, Hg in hair. In contrast, taking decoctions or pills was associated with lower levels of some metals (such as Cu in urine and Cd, Cu, Hg, Pb in hair), suggesting that some herbal medicines may have a chelating effect on heavy metals in the body. Overall, the results obtained in the study show a mixed picture and suggest that heavy metals contamination in herbs is sometimes present, but may also be counteracted by the potential for some herbal medicines to act as chelating agents. Further study must be followed to obtain more concrete evidence.

Keywords

References

  1. Caldas, E.D. ana Machado, L.L. (2004): Cadmium, mercury and lead in medicinal herbs in Brazil. Food Chem. Toxicol., 42, 599-603 https://doi.org/10.1016/j.fct.2003.11.004
  2. Cheng, T.J., Wong, R.H., Lin, Y.P., Hwang, Y.H., Horng, J.J. and Wang, J.D. (1998): Chinese herbal medicine, sibship, and blood lead in children. Occup. Environ. Med., 55, 573-576 https://doi.org/10.1136/oem.55.8.573
  3. Ernst, E. (2000): Risks associated with complementary therapies. In: M.N.G. Dukes and J.K. Aronson, Editors, Meyler's Side Effects of Drugs (14th ed.). Elsevier, 1649-1681
  4. Ernst, E. and Coon, J. (2001): Heavy metals in traditional Chinese medicines: a systematic review. Clin. Pharmacol. Ther., 70, 497-504
  5. Ernst, E. (2005): The efficacy of herbal medicine-an overview. Fundam. Clin. Pharmacol., 19, 405-409 https://doi.org/10.1111/j.1472-8206.2005.00335.x
  6. Fong, H.H. (2002): Integration of herbal medicine into modern medical practices: issues and prospects. Integr Cancer Ther., 1, 287-293; discussion 293 https://doi.org/10.1177/153473540200100313
  7. Georgiou, G.J. (2005): The discovery of a unique natural heavy metal chelator. Explore., 14, 44-51
  8. Goulle, J.P., Mahieu, L., Castermant, J., Neveu, N., Bonneau, L., Laine, G., Bouige, D. and Lacroix, C. (2005): Metal and metalloid multi-elementary ICP-MS validation in whole blood, plasma, urine and hair: Reference values. Forensic. Sci. Int., 153, 39-44 https://doi.org/10.1016/j.forsciint.2005.04.020
  9. Hasegawa, S., Nakayama, K., Iwakiri, K., An, E., Gomi, S., Dan, K., Katsumata, M., Minami, M. and Wakabayashi, I. (1997): Herbal medicine-associated lead intoxication. Intern. Med., 36, 56-58 https://doi.org/10.2169/internalmedicine.36.56
  10. Kabelitz, L. (1998): Heavy metals in herbal drugs. Eur. J. Herb. Med., 4, 25-29
  11. Ko, R.J. (1998): Adulterants in Asian patent medicines. New Engl. J. Med., 339, 847-854
  12. Ko, R.J. (1999): Adverse reactions to watch for in patients using herbal remedies. West J. Med., 171, 181-186
  13. Koh, H.L. and Woo, S.O. (2000): Chinese proprietary medicines in Singapore; Regulatory control of toxic heavy metals and undeclared drugs. Drug. Saf., 23, 351-362 https://doi.org/10.2165/00002018-200023050-00001
  14. Lim, S.S., Jung, S.H., Ji, J., Shin, K.H. and Keum, S.R. (2001): Synthesis of flavonoids and their effects on aldose reductase and sorbitol accumulation in streptozotocininduced diabetic rat tissues. Pharm. Pharmacol., 53, 653-668 https://doi.org/10.1211/0022357011775983
  15. Melchart, D. (2001): Quality assurance and evaluation of Chinese medicinal drugs in a hospital of traditional Chinese medicine in Germany: a five-year report. Altern. Ther. Health Med., 7, S24
  16. Mortada, W.I., Sobh, M.A., el-Defrawy, M.M. and Farahat, S.E. (2002): Reference intervals of cadmium, lead, and mercury in blood, urine, hair, and nails among residents in Mansoura city, Nile delta, Egypt. Environ Res., 90, 104-110 https://doi.org/10.1006/enrs.2002.4396