There is currently no established PEth level for acceptable lower risk alcohol intake,24,26 although a level of ≥8 ng/mL, the lower limit of quantitation is commonly used as an indicator of any alcohol use in the prior 21 days.16,37–39 As PEth 8 ng/mL represents the lower threshold at which the assay can reliably quantify alcohol exposure,34 we considered a PEth <8 ng/mL to represent no alcohol use and created two PEth levels (<8 versus ≥8 ng/mL) accordingly. We also considered a PEth variable with 3 levels (<8, 8–49, and ≥50), as PEth of ≥50 has been considered to indicate unhealthy alcohol use.
