For what it's worth, they address this (superficially) in their FAQ: > Are rainworks bad for the environment? > Heavens no! Once dry, rainworks are completely

For what it's worth, they address this (superficially) in their FAQ: > Are rainworks bad for the environment? > Heavens no! Once dry, rainworks are completely non-toxic, environmentally safe, and biodegradable. The solvent in Invisible Spray means you should not pour it down the drain, but when used as instructed, its solvent evaporates and does not enter the water system.