Some disturbing news for you from the English language German newspaper “The Local”. Apparently 1 in 5 Pretzels produced in Bavaria contain higher than recommended levels of aluminium.
A spokesperson for the Bavarian Federation of Bakers’ Guilds was quoted by the paper as saying that this problem has been known about for a long time. The longer the dough is in contact with the trays before cooking the higher the amount of aluminium that is transferred.
It has been suggested by the Bavarian Consumers’ Centre to ask your baker if they use aluminium trays and if so then perhaps choose a different snack for children.