Is there a noise floor for the sense of smell?

At very clean forest air conditions a cat can sense that a tuna tin can had been opened from many meters away. (Assuming she did not hear the click opening sound).


But it was also observed that another cat had come around from far away approaching the snaking food.


Is it like sound? At very low noise ambient conditions sounds from far away can be heard and picked up by a good microphone to a low noise preamp. See also Shure article on the non existence of a zoom microphone.