Time Delays in Transdermal Alcohol Concentrations Relative to Breath Alcohol Concentrations

Abstract

Aims: Monitors of transdermal alcohol concentration (TAC) provide an objective measurement of alcohol consumption that is less invasive than measurements in blood, breath or urine; however, there is a substantial time delay in the onset of TAC compared to blood or breath alcohol concentrations (BrACs). The current study examined the characteristics of the delay between peak TAC and peak BrAC. Methods: Data was aggregated from three experimental laboratory studies (N = 61; 32 men, 29 women) in which participants wore a TAC monitor and BrAC was monitored while drinking one, two, three, four and five beers in the laboratory. Analyses examined the sex-and dose-related differences in peak BrAC and TAC, the time-to-peak BrAC and TAC, and time lag between the peak BrAC and TAC values. Results: The times-to-peak were an increasing function of the number of beers consumed. At each level of beer consumption the peak TAC averaged lower than peak BrAC and times-to-peak TAC were longer than for BrAC. The time-to-peak BrAC and TAC was longer for women than men. The congruence between peak TAC and BrAC increased as a function of the beers consumed. No sex difference in the time lag between peak BrAC and TAC was detected. Conclusions: The congruence between TAC and BrAC and time lags between TAC and BrAC are related to the number of beers consumed. Peak values of TAC and BrAC became more congruent with higher doses but the time lag increased as a function of the amount of alcohol consumed. Short summary: The time delay (or lag) and congruence between transdermal vs. BrACs increases as the number of beers increases. Though sex differences are evident in peak transdermal and BrACs, no sex differences were evident in the time lag and the congruence between transdermal and breath alcohol concentrations.

Wearable Enzymatic Alcohol Biosensor

“…We recorded a peak BAC of 0.038% (110 nA), in good agreement with the calculated BAC of 0.05%. The response times are within the range of previously published values for transdermal alcohol [38].…”

“…There are two primary mechanisms by which alcohol is excreted by the skin: passive diffusion (i.e., insensible perspiration), and active pumping through sweat glands (i.e., sensible perspiration) [32]. The physics of diffusion that govern the relationship between blood alcohol and insensible perspiration result in time-dependent kinetics [33,34]; transdermal alcohol is often described as being "delayed" with respect to blood alcohol concentration [35][36][37][38], although the relationship can be more accurately described as a convolution [17].…”

Processing transdermal alcohol concentration (TAC) data to detect low-level drinking

“…Because drinking typically takes place during the nighttime hours and there is a 2.5–4.0 hour time delay in the onset of TAC data relative to the start of drinking (Barnett et al, 2017; Karns-Wright, et al, 2017), all data were analyzed based on a noon-to-noon 24 hour period rather than a midnight-to-midnight calendar day. In our previous analyses this attribution has proven reasonable, because even with calendar-based timeline follow-back methods, drinking is typically attributed to a particular day or “night”, even when drinking occurred past midnight.…”

Can an app Help Identify Psychomotor Function Impairments during Drinking Occasions in the Real World? A Mixed-Method Pilot Study

“…We attempt to minimize bias through the use of use of experience sampling methods, by using a computer interface, and including a picture reference of standardized drinks each time a user reported consumption over the last hour. Future work could use transdermal alcohol sensors to validate eBAC levels, but they have been found to be less useful in detecting lower drinking quantities as compared to self-reports 40 and BAC levels tend to lag behind consumption by up to several hours 41 . Despite exit-interview reports indicating that some individuals became more aware of their drinking due to self-monitoring, we did not find evidence of actual reductions in peak eBAC over days in study.…”