Use a bulb duster to apply a light dusting in cracks and crevices. This is recommended over dusting large, open areas. Boric acid is approved for crack and crevice treatment in kitchen and food preparation areas. Boric acid can be dusted into wall voids and spaces behind and under cabinets. These are insecticidal dusts that can be used for ant control.
Diatomaceous earth is made from fossilized diatoms, and silica gel is produced from sand.
Diatomaceous earth and silica aerogel are especially useful in wall voids and similar closed spaces. During construction and remodeling these dusts can be blown into such spaces, and in finished buildings they can be applied by drilling tiny holes in the walls. These dusts are also useful in crack and crevice treatments. Some products combine diatomaceous earth or silica gel with pyrethrins. Ant Baits Baits greatly reduce the amount of pesticide that must be used to kill ants.