Tips on Hazardous Household Chemicals Air fresheners: most air fresheners cover your nasal cavity with an oil film or release a nerve inhibitor that interferes with your sense of smell. Known toxic chemical products found in air fresheners: formaldehyde: highly toxic, known carcinogen. Phenol: When phenol comes into contact with your skin, it will cause skin swelling, burns, peeling, and even urticaria. It can lead to...