Lawn sand killed my herbs

I was looking for a way to improve drainage in my pot plants on my balcony, and tried to source some sand to put in them. The only one I could find was "lawn sand", which seemed innoccous to me, so I repotted my herbs and combined compost with the sand. Now I read the packet properly and see that it contains pesticides! This could be why my sage plant went black and my chives wilted a lot after repotting...

I've repotted these again, washed off all the sand, and put some good soil in and some fertiliser... but the question is, can I ever eat these herbs now? That is, if any of them survive.

AL