Junhyuk Jeon (Korea Racing Authority)

Junhyuk Jeon (Korea Racing Authority)

Junhyuk Jeon (Korea Racing Authority)

Jihee Han (Korea Racing Authority)

Nickel (Ni) is a carcinogenic heavy metal known to stimulate the production of erythropoietin (EPO) as cobalt (Co) does. Biomonitoring of Ni in 50 post-race urine samples from racehorses in Busan region was carried out by inductively coupled plasma mass spectrometry (ICP-MS). ⁶⁰Ni was tested instead of ⁵⁸Ni in order to avoid isobaric interference (⁵⁸Fe), and kinetic energy discrimination (KED) mode with high flow of collision gas (6.0 mL He/min) was adopted to eliminate polyatomic interference(⁴⁴Ca¹⁶O). Samples were collected over 5 weeks, and only the supernatant after centrifugation was used for analysis. The linearity of the analytical method was greater than 0.998, with detection limit (LOD) of 0.83 ng mL^-1 and limit of quantitation (LOQ) of 2.50 ng mL^-1, respectively. The accuracy of the method (relative error) was 1.1% for NIST SRM and 6.7% for fortified urine QC. One-way ANOVA statistical analysis was used to calculate the significance among gender groups. There was no significant difference among genders at 95% confidence level, with p-value of 0.113. Calculated urinary nickel concentrations were (13.87±8.35) ng mL^-1 for male horses(n=26), (16.80±6.34) ng mL^-1 for mares(female horses, n=14), and (20.53±9.73) ng mL^-1 for geldings(castrated horses, n=10), respectively. Only weak correlation between Ni and Co concentrations was observed (Pearson’s r = 0.34).