No they are found in the environment at large. One whiff of benzalkonium chloride can have an effect on someone with ADD who is on medication. I, personally, tend to drop things. Totally uncharacteristic of the normal ADD symptoms I would experience. It's like a slipstream to ADD.

The more extreme effects would only arise if, say, they put a portable toilet outside your place of work on a hot summers day. Or if there was a dead deer carcass near by your residence. Or if you were near a chocolate factory for an extended period of time.