Germicide, a substance or agent that kills microorganisms. A disinfectant is a type of germicide that kills germs that cause disease. An antiseptic is sometimes considered a germicide but actually is not because it merely prevents or slows the growth of microorganisms.
Burning ghost peppers is known to ward off elephants. Could chili peppers stave off sharks? The Aztecs thought so and dragged the peppers from strings through the ocean water.
Mealtime in the Kalahari Desert isn't exactly an all-you-can-eat buffet. Meerkats eat what they can get -- even poisonous scorpions. Why doesn't the venom hurt them?