Piperonyl Butoxide (PBO)

Piperonyl Butoxide (PBO) is an organic compound that, while having no pesticidal effect itself, enhances the effects of other pesticides. It was first registered in the USA in the 1950s, and is typically used in combination with pyrethrins. The EPA states that PBO has a low acute toxicity rating, however, they have not analyzed its effects in combination with other pesticides. When heated to decomposition temperature (200 Celsius), it produces an acrid smoke that is toxic.