For the last week or so, I've been testing the BACtrack Mobile, a portable smartphone breathalyser. The manufacturers sent me one after I asked them about a different device called BACtrack Skyn, which monitors your blood alcohol concentration through your skin via a bracelet. They had just won a design award for this new piece of technology but it isn't yet available to the public. So they sent me a traditional breathalyser - albeit one designed for the smartphone generation.

Like most members of the wine trade, I'm surrounded by booze for most of my waking hours. Compared to the average person, my alcohol consumption is bound to be higher. I was initially interested in the Skyn device because it can continuously monitor your alcohol intake, and I was curious to know how much alcohol enters the bloodstream during an average day of wine tasting.

The BACtrack Mobile detects your blood alcohol concentration from blowing into the mouthpiece, and you need to wait 15 minutes after eating or drinking to ensure the sample is accurate. That means that unlike the Skyn device, it can't continuously monitor alcohol consumption throughout a wine tasting, so instead I thought it would be interesting to know how intoxicating it is in general terms to be an average member of the wine trade. All I needed was a guinea-pig who would agree to drink alcohol and provide sample readings.

Luckily, I was willing to cooperate with myself, so after unpacking the device and downloading the app, I was ready to go.

I took readings on five different days and the results are as follows. In each case, I took a reading 15 minutes after my last drink of the day.

Those numbers only make sense in context, so here's what I drank on each day. 

• 16/06: roughly 375ml of 13% abv Côtes du Rhône (home, evening)
• 18/06: one gin and tonic plus roughly 375ml of 13% Savennières (home, evening)
• 19/06: 750ml of various wines (restaurant, lunch)
• 20/06: roughly 375ml of 10% Riesling plus two pints of 4.3% beer (bar, evening)
• 21/06: 375ml of various wines (bar, evening)

Converted into units, that equals as follows:

• 16/06: 5 units
• 18/06: 6 units
• 19/06: 10 units
• 20/06: 8.5 units
• 21/06: 5 units

Assuming these readings are all accurate, there is quite a disparity in my BAC when consuming similar quantities of alcohol, which is curious. For example, comparing the 18th with the 17th, one extra unit apparently doubled my BAC; and on the 20th I was 25% more drunk/less sober than on the 19th, despite consuming fewer units.

This appears to support the theory that drunkenness depends not just on volume of drinking but on other factors such as food and fatigue, but perhaps the more salient finding in this data relates to my overall average consumption and the current abstemious message that prevails around alcohol.

For me, drinking a whole bottle of wine over a three hour lunch with water on a Sunday lunchtime is not excessive. By most official measures, it's classified as binge drinking. The BACtrack app has a decidedly judgemental tone as it describes increasing levels of blood alcohol concentration - see right for screenshots of its feedback when my BAC reached 0.065.

Health risks related to excessive drinking (or indeed, excessive anything) should be taken seriously, of course, but there is a great deal of misinformation out there about what is excessive and what is safe. Using BACtrack Mobile is a convenient and well-designed method of monitoring alcohol consumption, and measuring how your body reacts to alcohol in different scenarios is enlightening, but it seems unlikely to alter my own judgement about how much I can drink.

But perhaps some more testing is required.