Chemistry Class, CMU.
The professor is explaining how toxic chemicals can get into the food supply and showing a scale of health problems occurring in different areas of the country based on river pollution.

Professor: OK, here’s where the northeast is on the scale. It’s already getting pretty high up there… Do you consider Pittsburgh to be in the northeast? I don’t. We’re our own place, so we must be OK… The midwest is even higher up on the scale, but it’s OK because I don’t consider Pittsburgh to be in the midwest either.