Nickel in equine sports drug testing – pilot study results on urinary nickel concentrations.

This study investigates the presence and potential misuse of nickel in enhancing performance in horse races. After analyzing 200 samples of horse urine post-competition, researchers found varying levels of soluble nickel, prompting the need for follow-up studies to establish safe levels of nickel concentration in urine and blood.

Background

• The illicit use of performance-enhancing substances is a common issue in both human and animal sports. Certain substances are known to boost erythropoiesis – the production of red blood cells – and are therefore prohibited.
• Cobalt is one such substance. In both human and equine sports, cobalt is listed as a banned substance due to its powerful erythropoietic effects.
• Nickel, another transition metal, has similarly been discovered in unregulated amounts in performance and recovery aiding products, leading to suspicions of its use as a substitute for the banned cobalt.
• Nickel exhibits properties similar to cobalt in inhibiting prolyl hydroxylase, an enzyme involved in oxygen sensing in the body.

Study Methodology

• In reaction to these findings, the researchers conducted a pilot study involving urine samples from 200 horses participating in different equestrian events across Europe.
• The urine samples were collected after the horse races and analyzed for nickel concentrations using a technique called inductively coupled plasma mass spectrometry (ICP-MS).

Results

• The analysis revealed nickel concentrations varying from below the limit of quantification (LOQ, 0.5 ng/mL) up to 33.4 ng/mL. The mean value, including the standard deviation, was 6.1 ng/mL.
• Overall, this suggests that the use of nickel-based supplements may be more prevalent than previously anticipated.

Conclusions and Future Recommendations

• Nickel is considered a micronutrient in horses and can be found in certain feed supplements. It is because of this reason that further studies are needed to establish safe and acceptable threshold levels for nickel in the blood and urine of horses.
• Future research involving larger sample sets, and comprehensive elimination studies with soluble Ni(2) (+) -salt species, are recommended to gain a deeper understanding of the role and potential misuse of nickel in equine sports.