Explainer

The Purell Defense

Can hand sanitizers really affect your blood-alcohol level?

Purell hand sanitizer

Rep. Vito Fossella of New York was convicted in a Virginia court on Friday on charges of drunken driving. A second hearing will be held to determine whether Fossella’s blood-alcohol content at the time of his arrest was above 0.15, which would require a five-day jail term. A defense expert claimed that Fossella had used Purell several times on the day he was arrested and that the ethanol in the hand sanitizer affected his blood-alcohol reading later that night. Can hand sanitizer applied to the skin really affect a breath alcohol test?

Probably not. A 2006 study among Australian health care workers tested this very question. Twenty workers applied Avangard—a hand sanitizer with 70 percent ethanol (compared with Purell’s 62 percent)—30 times during one hour, mimicking the usage in intensive-care units. One to two minutes after the final exposure, six of the workers did show a slight bump in breath-ethanol levels—between 0.001 percent and 0.0025 percent, about the same effect as one-tenth of a beer on an average-size male. Ten to 13 minutes after the final application, however, all the health care workers’ breath-ethanol levels had returned to zero. In Fossella’s case, a period of several hours separated his Purell usage and his breathalyzer test: He claimed to have used the hand sanitizer during the afternoon of April 30 and wasn’t pulled over until just after midnight.

It’s also very unlikely that alcohol would have remained on Fossella’s hands and thus affected the Intoxilyzer 5000’s analysis. Except for the trace amounts that get absorbed by the skin, the ethanol in the sanitizer would have dissipated once the liquid itself evaporated.

Drinking Purell is another story entirely, however. At 62 percent ethanol or roughly 120 proof, the sanitizer is about as alcoholic as some stronger kinds of rums and whiskeys. But even so, Fossella would have had to have drunk enough Purell to make himself sick in order for traces of it to remain in his blood around midnight.

In recent years, defense attorneys have questioned the reliability of breath-alcohol analyzers themselves. Some have claimed, for example, that fluctuations in voltage levels can affect readings. In Tuscon, Ariz., breath tests in more than 100 cases involving the Intoxilyzer 8000 were thrown out this year because the machine’s manufacturer, Kentucky-based CMI, would not release the Intoxilyzer’s software source code. Last month, CMI settled with the Minnesota Department of Public Safety and agreed to release the code for the Intoxilyzer 5000 model after the department filed a federal lawsuit to obtain it.

Bonus Explainer: Can putting too much Purell on your skin get you drunk? Maybe. There have been cases of small children becoming intoxicated after prolonged skin exposure to alcohol—a 2-year-old girl in Germany lost consciousness after ethanol-soaked bandages were applied to damaged skin and left overnight. (Her blood-alcohol level reached a whopping 0.8.) A similar case in Italy involved a 1-month-old who developed “unexplained lethargy” after having had alcohol-soaked gauze pads applied to her umbilical stump for several days. Adult cases are extremely rare, but during the SARS epidemic, a 45-year-old Taiwanese woman died after soaking in a 40 percent ethanol bath for 12 hours in the hopes that it would rid her of the infection.

Explainer thanks Bruce Goldberger of the University of Florida, Bruce Jackson of MassBay Community College, and Stefan Rose of Florida International University. Explainer thanks reader Karen W. Ramsey for asking the question.