or, you know. not criminalize drug use.
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Opium contains 50 different alkaloid opiates. The most common metabolism of opiates is to be ultimately converted to morphine. Heroin rapidly enters the CNS but is quickly metabolized into 6-monoacetylmorphine (6-MAM) and then morphine. Given that pathway, differentiating the two would be tough. Not an analytical chemist, certainly, and there are probably ways to look at secondary and tertiary metabolites, but since these tests are basically of the “quick and dirty” variety, I doubt there would be much push for that. Not air or right, but what it is.
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Thanks for your considered response.
To be clear bagels are the delivery medium like the syringe. The test is between poppy seeds and heroin, both coming from different parts of the same plant. Why is a smattering of around 100 or so poppy seeds on a bagel still after 30 years causing confusion in a drug test?
I guess a comparison would be alcohol testing. The difference between 3 or 4 drinks could be a DUI penalty where we are talking eating a crepe flamed with brandy vs drinking the bottle of brandy. For this still to be a testing problem after 30 years is it the nature of opioids that can’t be measured so precisely or is it a systemic failure in developing a more accurate test?
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Field BAC tests are also prone to false positives for certain metabolic disorders and for people who have very recently done extreme exertion.
I think the big difference is that society doesn’t benefit from criminalization of drugs, but definitely benefits from enforcement of DUI laws.
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Yep. It’s the time and money factor that means you’re going to do that for an initial round.
Same with the Ion Mobility detectors and the swabs TSA use. Anything beyond “hey, this is maybe a positive” is going to have false positives.
Often you’d rather “err on the side of caution,” and trade extra false positives for zero false negatives. Especially in a security and a safety situation.
Because the test is OVERLY sensitive, and cannot distinguish between the two. A better test would cost more money, and time. So, it’s a systematic failure in part because the affordable options can’t measure specifically. (Precisely/ precision meaning how many decimal places you could read the test too. I.e sensitivity. So, it’s sensitive, but not selective)
Yep. Have to measure it against public benefit. Here, I’d rather NOT have ‘men with guns’ operating under less than sober conditions.
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I love that they tested this. At the beginning of the video my first thought was those bagels they showed seemed skimpy compared to poppy seed bagels I’ve had in New York that were coated almost until they were black on top with a thick layer of them… but even those rather skimpy poppy amounts resulted in a positive test. Nuts!!
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I would go further and say stop doing random drug tests period.
Sure there are some medical uses for sensitive test, maybe even legal ones but I have never heard an argument for broad drug testing that makes any sense outside of vilifying drug users at all cost.
Aside:
Random tests are always going to be a balance of prevalence controlled variables (positive and negative predictive value). I won’t bore people with a math lesson but sensitivity and specificity don’t scale well to understand how a test works in a population. The number of False positives and negatives depends on what fraction of people you are testing actually have what you are looking for. Making a reliable test for rare things at population scale is hard.
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Tangentially – we’ve got a chocolate bar flavored with real rum here in Finland, called Da Capo. The amount in a single bar is very small, but it’s enough to show up in a breathalyzer test if one is taken soon after eating the bar.
This caused a stir some years ago, when the bars were sold at the canteen of a nuclear plant, and several plant workers got false positives from a breathalyzer test. (There’s unsurprisingly a zero-tolerance policy for alcohol at the plant: if the breathalyzer shows any alcohol, you’re not allowed to work.)
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Older testing recommendations used lower threshold levels that easily were crossed by poppyseed foods. Poppyseed products can spike someone into the 1200 ng/ml range for morphine (think poppyseed stuffed things rather than bagels). For a long time the common threshold was 300ng/ml. This lead to a ton of false positives. The federal standard was raised to 2000 a while back, with it being 3000 in certain cases. That lowers the length of time you can get a detection result, but largely eliminates false positives from eating poppy seeds. Depending on dose and a bunch of other things that might drop the detection window from three days to two. In exchange you give up a false positive rate that was high enough that most positive tests were false.
If you want to avoid that issue there are metabolites that are in heroin, but not in poppy seeds, but the tests cost more and have a shorter detection window in urine. But you shouldn’t be making any decisions based on urine tests alone without confirmation from other tests.
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In short, the breathalyser test is asking “have you had too much alcohol to drink in the last few hours”. The opiate test is aiming for “have you ever taken opiates”. So they set the test so sensitive that it triggers on effing poppy seeds. Because there’s a lot similar between eating a bagel today and having had an opioid pill days ago acording to the test.
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There is no way to tell the difference because poppies are how we get opioids. That’s what the test tests for and why people are warned not to eat poppy seeds when they are being tested.
It’s easy for non-addicts to not eat poppy seeds. It’s extremely hard for addicts not to take opioids. That’s why the test is useful.
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