How does lime powder kill termites?

Many concentrated essential oils from plants such as rosemary, eucalyptus, peppermint, clove, cedar, wintergreen, citrus oils (such as lemon, grapefruit, orange, and lime oil) and thyme, are powerful insecticides. For most of these, including the citrus oils, the main active insecticide is limonene, a solvent that kills the insect by penetrating its waxy cuticle and disrupting its nervous system.