I quit using fabric softner sheets quite a few years ago for anything, other than if you want to keep mice out of something. #1 I personally find the smell "not good" gives me instant headaches(miagranes) #2 One day my son "caught" a mouse and at the time was doing a project so was going to keep him for the project alive (a living diarama(sp)). He wanted to give him something so use as a nest and gave him dryer lint(which was from a dryer that uses dryer sheets.) (We completely forgot that mice do not like dryer sheets.) Well, my son put the lint in with the mouse, not realizing what was going on the mouse started freaking out but we did not put two and two together, He died within 2 hours. Since then I guess I just have a hard time using it. If it does that to a mouse that quickly I do not care to use.
I would be concerned about the chemical and what it would do over time too.