There have been a lot more complaints about this recently. I wonder if some regulation or other has forced screenwash manufacturers to change the ingredients.
Screenwash is just something to lower the freezing point + something to clear off oily road spray. The antifreeze is always some kind of industrial alcohol.
I mix my own from meths + washing up liquid. It doesn't take much meths to kill off any bacteria, and you can use scented washing up liquid if you want. My screenwash smells of meths, though
Apparantly washing up liquid is thought to damage the paintwork, but looking for evidence all I can find is a avgue disquiet about it affecting wax polishes. I can' t see that being a big issue in the concentration it's used in the washer bottle.