Since several months i notice that on slow speeds and for a short periods of time (1 minute) the AC will emit a smell
of chlorine (kind of).

Before when it happened it was just a little bit of smell and not so frequent but now it is almost 1 minute every drive.
I am guessing that on the highway the amount of wind surrounding the car take the smell a way, what i dont understand is what is happening in the AC system, is there a valve that open and close some time that can cause it?
For sure if AC is off no smell but it can be the AC system is only the carrier of the smell into the car and not really the source
Will be hard to reproduce in the garage.

I am a bit scared that this smell is toxic therefor when its occurring i stop the AC and open the windows.