Introduction: This study assessed the in vitro accuracy, precision, specificity, and measurement uncertainty of three smartphone-connected breath alcohol analyzers marketed for personal use.Methods: Breath alcohol analyzers were tested against known reference standards ranging from 0.020 - 0.250 g/210LResults: At the 0.080 g/210L concentration, the measurement uncertainty was determined to be ± 0.013, 0.004, and 0.006 g/210L for the BACtrack Pro, C8, and C6, respectively, at the 95% coverage interval. The analyzers showed an apparent ethanol response to isopropanol and methanol but not to acetone.Conclusion: The smartphone-connected breath alcohol analyzers showed the ability to measure vaporous ethanol with confidence in the results. Potential uses include self-tracking, family law, medicine, and workplace testing.

A discrete wrist-worn transdermal alcohol monitoring device, the BACtrack® Skyn™, was evaluated in a subject over three drinking sessions. The relationship between transdermal alcohol concentration (TAC) and breath alcohol concentration (BrAC) was evaluated. The relationship amongst contemporaneous TAC/BrAC measurements revealed an R2 of 0.65, while the relationship in the 45-minute post-drinking phase revealed an R2 of 0.89. Results obtained show promise for its use. Further research is needed with many subjects in real-world drinking situations.