Since wintergreen oil and water works so well I'm not sure why I'd want xylene in there at all.
When I need brake cleaner or carb cleaner I sometimes reach for the toxic flammable chemicals. But I can also do a lot of work -- even on brakes and carbs -- with more benign stuff. Wintergreen oil clearly releases volatile compounds so it's not totally benign but 2 oz of wintergreen oil mixed with water certainly won't make a photo op like that.