Using simulation modelling to examine the impact of venue lockout and last‐drink policies on drinking‐related harms and costs to licensees

Abstract Objective: Many variations of venue lockout and last‐drink policies have been introduced in attempts to reduce drinking‐related harms. We estimate the public health gains and licensee costs of these policies using a computer simulated population of young adults engaging in heavy drinking. Method: Using an agent‐based model we implemented 1 am/2 am/3 am venue lockouts in conjunction with last drinks zero/one/two hours later, or at current closing times. Outcomes included: the number of incidents of verbal aggression in public drinking venues, private venues or on the street; and changed revenue to public venues. Results: The most effective policy in reducing verbal aggression among agents was 1 am lockouts with current closing times. All policies produced substantial reductions in street‐based incidents of verbal aggression among agents (33–81%) due to the smoothing of transport demand. Direct revenue losses were 1–9% for simulated licensees, with later lockout times and longer periods between lockout and last drinks producing smaller revenue losses. Conclusion: Simulation models are useful for exploring consequences of policy change. Our simulation suggests that additional hours between lockout and last drinks could reduce aggression by easing transport demand, while minimising revenue loss to venue owners. Implications for public health: Direct policies to reduce late‐night transport‐related disputes should be considered

Use of a chemical probe to increase safety for human volunteers in toxicokinetic studies

International audienceTo avoid interspecies extrapolation in toxicokinetics and drug development, it is convenient to directly develop human data. In that case, exposure dose should pose null or negligible risk to the exposed individual, but still be sufficiently high to allow quantification. We propose to reduce the dose received by human volunteers during exposure, and to compensate for loss of information by exposing the same volunteers to a nontoxic agent. This method was applied to develop 1,3-butadiene (BD) exposure protocols for humans. To study the potential of such a procedure, we worked with simulated data. Three exposure times (20, 10, and 5 minutes) and four exposure concentrations (2,1, 0.8, and 0.5 ppm) were used to define 12 inhalation exposure scenarios for BD. Isoflurane was used as a probe, with simulated exposure of 20 subjects to 20 ppm isoflurane during 15 minutes. Isoflurane or BD-exhaled air concentrations were supposed to be measured 10 times. A three-compartment physiological toxicokinetic model was used to jointly describe BD and isoflurane data. For each subject, BD data were analyzed, in a Bayesian framework, either alone or together with the isoflurane data. The precision of BD metabolic rate constant or fraction metabolized was increased, and bias reduced, when BD and probe data were considered jointly. An exposure to 10 ppm x min BD and 300 ppm x min isoflurane gave equivalent precision and bias as a unique exposure to 40 ppm x min BD. The BD dose received by volunteers could therefore be at least quartered if BD exposure was supplemented with that of a probe