I read the article on lead intoxication due to adulterated marijuana with great interest (1). The authors have done a great service in alerting a wide readership to a thus far little known danger. However, the therapeutic scheme in the figure—which provides for chelator therapy in men with a blood lead concentration >250 µg/L and in women above 150 µg/L—does not make sense at all. The guideline of the German Association for Occupational Medicine and Environmental Medicine (2) was incorrectly cited. The guideline cites human biomonitoring values I and II as stipulated by the German Federal Environment Agency (3), which does not make a recommendation for chelator therapy if the value measured is only marginally in excess of HBM value II. From the agency’s publication it is clear that a higher value than HBM value II is not automatically an indication for chelator treatment (chapter 12.4, on chelators). The text of the publication does, however, slightly revise the indication for chelator therapy, by saying that such therapy is indicated if lead concentrations are above 400 µg/L, but even this statement is not acceptable as it stands. The clinical picture, together with the blood lead concentration, is the deciding factor. In the individual case, chelator therapy can have serious side effects. The indication therefore has to be defined critically, while balancing the risks and benefits, in order to prevent harm to the patient. In my opinion, chelator therapy should be given only with a very strict indication. The clinical picture should prompt the therapeutic decision.
References
- 1.Busse FP, Fiedler GM, Leichtle A, Hentschel H, Stumvoll M. Lead poisoning due to adulterated Marijuana in Leipzig. Dtsch Arztebl Int. 2008;105:757–762. doi: 10.3238/arztebl.2008.0757. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. http://www.dgaum.de.
- 3.Kommission „Human-Biomonitoring“ des Umweltbundesamtes. Stoffmonographie Blei Referenz- und Human-Biomonitoring-Werte (HBM) Bundesgesundheitsbl. 1996;39:236–241. http://www.umweltdaten.de/gesundheit/monitor/pbmono.pdf. [Google Scholar]