Dr Greengood Commercial Bed Bug Killer and Bed Bug Preventative is 100% non-toxic to humans, pets and the environment. It has been certified by an independent testing laboratory, for safety and efficacy. It kills bed bugs, upon contact, and then adheres to treated surfaces and continues to kill for 12 months after application. The economy size 20 oz. bottle will continue to kill for a minimum of 30 days after application. Dr Greengood will not stain.