SAFETY TIP The American Association of Poison Control Centers (AAPCC) describes a poison as a substance that is used in the wrong way, in the wrong amount or by the wrong person. In addition, the AAPCC states that household cleaning products are one of the most common poisons, listing toilet bowel cleaner as one of the most dangerous. Mixing bleach with toilet cleaner creates a poisonous gas that can cause adverse health reactions, including death.