Toyota previously showcased its own system that used steering-wheel mounted sensors that could detect alcohol in the blood through the driver’s sweat from their palms. Toyota’s version could even be activated once the car is in motion if it detected that the driver’s steering patterns were becoming unsteady.
We're sure many motorists would find it annoying having to use a breathalyzer everytime they start the car. Also, there are several major hurdles preventing the introduction of such devices. Firstly, current breathalyzer technology can be inaccurate at times, and, secondly, drivers could simply get another sober person to start the car or in the case of the Toyota system, wear gloves.