Why are my stored pulses developing a powdery dust and where is it coming from?

That fine powder, often called grain dust or frass, is usually a sign of insect activity in the store, not just settling. As storage insects like the pulse beetle and weevils feed and bore through the seed, they leave behind powdered grain, broken bits, cast skins and droppings, which collect at the bottom. So the powder is a clue to look closer: check for small round holes in the pulses, tiny beetles, and hollowed-out seeds. If the infestation is light and caught early, you can still save much of the dal: sun dry it on a clean sheet for a few hours to kill eggs and young stages, sieve out the powder, holed and damaged seed, then store the clean, dry pulses in a filled airtight container so the seal stops the beetles. If the seed is heavily holed and hollow, that portion has lost food value and should be removed. Going forward, store only well-dried, clean pulses in airtight or hermetic packing, clean the bin between seasons, and never mix new stock with old infested grain. Dry neem leaves or ash can help as an extra repellent layer. Avoid chemical fumigants at home, as they are hazardous and restricted. Confirm safe handling with your KVK.