I haven’t done any real labwork in about a decade, so probably a dumb question, but wouldn’t repeat distillation be a viable option for a control like that? Or are you suggesting the gloves might’ve been the culprit?

I know you’ll always get some nanoplastics carried over through aerosol droplets able to survive, but I’d naively expect you could still get a few orders of magnitude cleaner than the ordinary DI tap.