Lead free solders.
Yes I was referring to the kind sold for plumbing nowadays. However, even the best lead free solder is crap for some applications. Particularly for printed circuits in critical areas, ie. cruise missiles and similar devices where malfunctions can be disastrous. These problems have been showing up in parts sourced in Europe where lead has been banished from the workplace. Gee, I grew up drinking water from lead pipes, learned to make sheet lead flashings and was still pouring lead joints on cast iron pipe as late as the sixties. Oh, come to think of it, maybe THAT'S why I'm so stupid.
nial