IC marking
With most ICs having just a basic printed label on them, replacing high grade military spec components (certified to work from -50C to +100C or better) with commercial ones (rated for -20C to +70C) is easy. The only way to avoid this is to NOT buy from middlemen that are not certified by the manufacturer of the products. (Recycled ICs should be detectable by close inspection as the soldering and desoldering operations will leave traces on the IC contacts.)
As with aircraft parts, military parts that need the ability to work in extreme environments should be tracked from the manufacturer through to the final assembly. This of course had the unfortunate effect of raising the price horribly (10x versus commercial equivalents is not uncommon).