The first data from breathalyzer selfies--measurements of blood-alcohol content by a new smartphone app--show that users drank the most on the weekend of the summer solstice, the longest day of the year.
San Francisco-based breathalyzer manufacturer BACtrack reported Wednesday the highest average blood-alcohol content (BAC) from April 2013 to April 2014 was registered on Saturday, June 22, at 0.115 percent. The legal definition for drunk driving is 0.08 percent.
The data shed light on drinking patterns, which can guide highway patrols and others determining when to focus drunk-driving enforcement.
But the primary purpose of the $149.99 BACtrack Mobile, which consists of a breathalyzer that sends readings via Bluetooth to a smartphone and was introduced in 2013, is to raise people's awareness of how drinking affects their BAC and therefore causes impairment, said BACtrack founder and Chief Executive Officer Keith Nothacker.
BACtrack Mobile data confirmed that one of the most booze-fueled holiday was New Year's Eve (an average of 0.095), followed by Super Bowl Sunday (0.087) and Valentine's Day (0.081). The average BAC on Mother's Day (0.069) exceeded that on St. Patrick's (0.057).
The mobile app is intended to let users check their blood-alcohol content before getting behind the wheel, but 15 percent of the 100,000-plus tests were on friends and others. That seemed wise: tests on friends found an average BAC of 0.085, while selfies averaged 0.066.
Not surprisingly, the highest average BACs were recorded after Saturday-night drinking, when they peaked (0.113) at 4 a.m. Sunday.
The geography of drinking also offered some surprises. Users in Montana and South Dakota had the highest average BAC, at 0.101 percent, while the lowest were in New Hampshire (0.012), Delaware (0.027), and Utah (0.031), where the dominant Mormon Church forbids alcohol consumption.
But the BACtrack Mobile data jibes with arrests for drunk driving. Montana had the highest number of arrests per capita in 2013. New Hampshire had the lowest.