My friend who’s a nurse has noticed that everything like lancets, needles, syringes, ear piercing studs, and whatnot now have expiration dates on. They didn’t used to as late as the 1990s. So why did this change?
Since the expiration dates were several years after manufacture, was the assumption that everything would get used up well before it expired?
Was there some law at some point that dates needed to be added?
Were people getting infections because the nurse pulled out stock from the back of the closet?
How likely is it to get an infection from an expired needle that’s in a sealed package anyway? It doesn’t seem like smooth, clean steel is a hospitable place for bacteria whether or not it’s still airtight. Does it depend on what it is, say a immunization needle that goes into a muscle has more risk than a lancet that just nicks the skin? Or an insulin infusion set, IV line, or ear piercing stud that stays in the skin an extended time rather than just momentarily?
Is the risk really low, but this is a CYA type of deal?
I asked my friend who’s a diabetic if he pays attention to this, and he says he’s used needles and insulin pump infusion sets that were years expired and reuses lancets “until they start to get dull” and he’s never had a problem. On the other hand another friend claims she got an infection from a tetanus shot, presumably with non-expired components.
I don’t know either. But for the non-clinical research-use-only assays I once supported, expiration dates were definitely used to get customers to buy new kits.
I did tech support, and if a kit or product was expired and the customer called in for troubleshooting, the company policy was “we can’t support an expired kit/product. You need a fresh product/item.”
Over long time spans, these things will start to degrade. Plastic will get brittle and crack. Preservatives will dry up or become ineffective, along with other changes. Without an expiration date, the manufacturer could be on the hook when you use a 10+ year old needle that falls apart in your hands. However, the expiration dates are far sooner than necessary. They probably don’t have exact timeframes for when this type of decay sets in.
Expiration intervals on sterile medical devices are based on testing; the longer your study, the longer the expiration interval. These companies will test long enough to get a competitive result - a shelf-life short enough to guarantee sterility, but long enough that competitors can’t slap on a longer date without adding unreasonable costs.