CA AB455

Requires sellers of single-family residential properties to disclose in writing any actual knowledge of tobacco/nicotine product smoking residue or history of occupants smoking on the property

Defines "thirdhand smoke" as toxic chemical residue left behind by tobacco smoke that accumulates in carpets, walls, furniture, and building materials, persisting for years after smoking stops

Mandates the Department of Toxic Substances Control to update the Homeowners' Guide to Environmental Hazards to include a new section on thirdhand smoke

Delegates the responsibility for creating the thirdhand smoke guide update to the Center for Tobacco and the Environment at San Diego State University to offset costs

Requires the guide update to educate consumers on thirdhand smoke as an environmental hazard affecting real property, its significance, mitigation options, and sources for additional information