Abstract
Misuse of performance-enhancing substances in sport remains a persistent threat to the values of fair competition, with estimated doping prevalence far exceeding adverse analytical findings in routine testing. This highlights the need for improved surveillance tools capable of rapid and simple, on-site screening methods. This proof-of-concept study evaluated atmospheric solids analysis probe-mass spectrometry (ASAP-MS) as a minimally complex, high-throughput, and potentially deployable approach for detecting prohibited substances in black market products. Sixteen pharmaceutical products previously confirmed to contain prohibited substances were blind-analysed using ASAP-MS, alongside eleven third-party batch-tested sports supplements. Resultant multi-channel spectra were interrogated manually for the presence of known precursor and product ions. In addition, a compound library was developed and applied using software-driven matching. At least one prohibited substance was detected in all products without generating false positives in certified supplements. Manual spectral review identified only 68% of individual substances correctly. Initial issues with false positive detection of trenbolone in testosterone ester products using the software-driven approach were iteratively optimised through alteration of match score thresholds. This achieved 96% correct substance identification and 100% detection for an adverse finding. Moreover, investigation of diagnostic precursor ions via heatmaps offered a complementary and additional reporting tool to reduce false negatives. This work demonstrated that ASAP-MS, with tailored software-driven analysis, provides reliable near-real-time qualitative screening of prohibited substances. More broadly, this supports the potential for portable, rapid mass spectrometry-based screening platforms to strengthen forensic intelligence, accelerate anti-doping investigations, and enhance athlete protection by complementing laboratory-based confirmatory testing in sport.