Cobalt

Cobalt, an element in the transition metal group, has been banned in sports since January 1, 2015. As a trace element, it is essential for the human body, as it is a component of vitamin B12 (cobalamin). In larger quantities, however, cobalt is toxic. Since cobalt salts are now marketed as dietary supplements to increase erythropoiesis (increased production of red blood cells), the use of cobalt is classified as doping-related.

World Anti-Doping Agency (WADA) Prohibited List

1. Erythropoietins (EPO) and agents affecting erythropoiesis, including, but not limited to:

1.1 Erythropoietin receptor agonists, e.g., darbepoetins (dEPO); erythropoietins (EPO); EPO-based constructs [EPO-Fc, methoxy polyethylene glycol-epoetin beta (CERA)]; EPO-mimetic agents and their constructs (e.g., CNTO-530, peginesatide).

1.2 Hypoxia-inducible factor (HIF) activating agents, e.g., cobalt; daprodustat (GSK1278863); IOX2; molidustat (BAY 85-3934); roxadustat (FG-4592); vadadustat (AKB-6548); xenon.

1.3 GATA inhibitors, e.g., K-11706.

1.4 Transforming growth factor beta (TGF-β) inhibitors, e.g., luspatercept; sotatercept.

1.5 Innate repair receptor agonists, e.g., asialo EPO; carbamylated EPO (CEPO).

Excerpt from the list as of January 1, 2026

 

Relevance to Doping and Detectability

Physiology

Cobalt salts activate hypoxia-inducible transcription factors (HIF) and increase the expression of HIF-dependent genes, such as the gene for erythropoietin (EPO). Cobalt salts could therefore be misused by athletes to improve endurance performance.
Jelkmann W: The disparate roles of cobalt in erythropoiesis, and doping relevance. Open J Hematol 3 (2012) 1–9. download
—see also HIF stabilizers

The effects of low doses of cobalt on hemoglobin mass and endurance performance in male subjects were demonstrated by Hoffmeister et al. (2018) (see publication).
Another study by Hoffmeister et al. (2019) examines the minimal cobalt dose that still has a potential effect on blood parameters.

Hoffmeister T, Schwenke D, Krug O, Wachsmuth N, Geyer H, Thevis M, Byrnes WC, Schmidt WFJ. Effects of 3 Weeks of Oral Low-Dose Cobalt on Hemoglobin Mass and Aerobic Performance. Front Physiol. 2018 Sep 19;9:1289. doi: 10.3389/fphys.2018.01289. eCollection 2018
Download the article 

Hoffmeister T, Schwenke D, Wachsmuth N, Krug O, Thevis M, Byrnes WC, Schmidt WFJ. Erythropoietic effects of low-dose cobalt application. Drug Test Anal. 2019 Feb;11(2):200-207. doi: 10.1002/dta.2478. Epub 2018 Sep 8
see abstract

Detection of Doping

Cobalt can be detected using mass spectrometric methods.
However, small amounts of cobalt are also ingested through food and excreted in urine. To conclusively detect a doping violation, a threshold value for cobalt in urine or blood would therefore need to be established

Krug O, Kutscher D, Piper T, Geyer H, Schänzer W, Thevis M. Quantifying cobalt in doping control urine samples - a pilot study. Drug Test Anal. 2014 Nov-Dec;6(11-12):1186-90
Abstract

Thevis M, Krug O, Piper T, Geyer H, Schänzer W. Solutions Advertised as Erythropoiesis-stimulating Products were Found to Contain Undeclared Cobalt and Nickel Species. Int J Sports Med. 2016 Jan;37(1):82-84.
Abstract