I do not know if this is related subjectwise Nem, but it just shows what "signals" our bodies can give off as to our health and use of substances. A friend is an auto tech at the Mercedes dealership here in Austin. He used to be a potsmoker. Not anymore, and at least for a couple of years. I asked him what inspired him to quit. He was like "dude, they get a strand of my hair for drug screens here", and it seems that the hair strand cannot be cheated on like with some urine tests.
I also know one person who attends a group at the VA clinic who has an state authorized electronic monitoring device on his ankle, and not only does it have GPS tracking, it also detects when a person has been drinking! It monitors his vital signs and even sweat content!
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But never fear, soon he will not be alone. For Toyota has already designed a steering wheel that can tell if a person has even had one drink, and those wonderful people at MADD are pushing the politicians to make it a Federal requirement on ALL vehicles. Nevermind the fact that cell phone drivers have taken the crown away from the drinkers in causing automotive accidents.
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Ever since 2004.