Wow - that's a whole pile of leaps of faith - and "logic" - to connect the dots the way this guy does.
One obvious problem - at least for me - is the implication that "the nicotine did it" when trying to make a connection between nicotine intake during pregnancy and subsequent schizophrenia. What the good Mr. Chapman fails to site was how that nicotine was introduced during pregnancy - undoubtedly from smoking. Along with smoking's very own "soup" of chemicals beyond nicotine intake.
Once again - correlation does not equate to causation. (Also known as "there are lies, and there are statistics.")
BTW: I did not know we are inhaling "...a soup of vaporized flavouring and other chemicals..." Yep - no biases showing there.
And things like that...