Cobalt chloride administration in athletes: A new perspective in blood doping?

Ist Chimica e Microscopia Clinica, Università di Verona, Verona, Italy.
British Journal of Sports Medicine (Impact Factor: 5.03). 12/2005; 39(11):872-3. DOI: 10.1136/bjsm.2005.019232
Source: PubMed


Blood doping is an illegal and unfair way of enhancing athletic performance by increasing the oxygen carrying capacity of the blood. Currently used methods usually involve stimulation of erythropoiesis. Gene therapy targeting the hypoxia inducible factor pathway may be an attractive alternative to traditional blood doping techniques. Hypoxia activates a large number of genes with essential roles in cell and tissue adaptation to low oxygen. Cobalt chloride is a well established chemical inducer of hypoxia-like responses such as erythropoiesis. Cobalt supplementation is not banned and therefore would not be detected by current anti-doping testing. Although there is as yet no direct or anecdotal evidence of cobalt chloride administration to athletes, its use should be warned against as being not only unfair but potentially dangerous.

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Available from: Giuseppe Lippi, Mar 10, 2014
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    • "In addition, cobalt supplementation may facilitate tolerance to hypobaric hypoxia (Shrivastava et al., 2008), which could be related to the modulation of HIF-regulated genes in order to promote oxygenation. Cobalt chloride supplementation has been evoked as a potential doping strategy in athletes (Lippi et al., 2005). To date, cobalt is not explicitly prohibited by world anti-doping agencies, despite its potential toxicity in the case of abnormal exposure. "
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    • "These pleiotropic effects of cobalt raise serious concern for potential toxic and carcinogenic effects of long-term occupational cobalt exposure in hard metal industry [19], and for attendant health risks to the use of cobalt– chromium hard metals in hip joint arthroplasty [9] [10] [20] and in dental restorations and implants [21] [22]. Moreover, suspicion has recently been raised that cobalt may be misused by athletes as an attractive means of doping [23] [24] that may enhance aerobic performance even more effectively than doping by Epo or related means (see [25] [26] [27]). The results of the present study imply that for biomonitoring of long-term cobalt exposure it could be appropriate to measure the cobalt content in red cells to give, compared with timed or incompetition whole-blood and serum analysis, an average value for the exposure over the 120 days life span of red cells. "
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