Second Hand Smoke / Passive Smoking

What is the evidence that passive smoking is detrimental to health? What is the evidence that it is not?

i do not know but the only negative effect smoking gave me is a cough.

A cough, yes that is the main effect on me from passive smoke, but also gives me a severe headache and nausea. In pregnancy I would just throw up in the street from the smell of smoke. Today I had to move seats on a bus because a man who stank of tobacco sat by me and even the third hand smoke on the smoker's clothes gives me nausea and headache, the smell is disgusting on some heavy smokers. They should ban them from the buses when they smell that bad.
Actual evidence of harm is clear enough from all the smokers dying of lung diseases.

The topic of this thread is clear. The purpose is to present actual evidence, one way or another. Stay on topic, please.

Thank you.