Q: I don't understand why we have to be so careful on Pesach about buying products like salt and sugar that are certified kosher for Passover, just in case they've been contaminated by a bit of chametz. During the year we're not so worried about them becoming contaminated with general non-kosher food! My tutor explained that it is because of the rule of non-kosher food becoming invalidated if it is mixed in with kosher food sixty times its volume. She said that this rule doesn't apply to chametz and therefore we have to be extra careful. Where's the logic in this? It doesn't make sense to me.
A:While throughout the year, one must be careful to avoid non-kosher products, this is achieved by buying either kosher-certified foods or sticking to the huge range of general products listed by the LBD and other authorities. Yet at Pesach-time, it is normal practice to purchase all processed foods under supervision, even those like salt and coffee that are unlikely to contain chametz.
The rabbis explain that the Pesach restrictions differ from year-round kashrut in several ways:
1) Eating chametz on Pesach is a more severe prohibition than most regular food prohibitions.
2) Unlike other prohibited foods, chametz is permitted 51 weeks of the year. Since we are used to eating chametz, greater diligence is needed to avoid eating it in error.
3) For these and other reasons, the usual principle that forbidden substances are nullified in a mixture 60 times their volume, does not apply.
As such, except in unusual situations, we take great care to actively remove even the possibility of chametz from the foods we eat on Pesach. Do ask your rabbi for details, especially if your circumstances are difficult. Have a wonderful and kosher Pesach!