No as dangerous as first hand. Common sense will be, first hand smoker already such in all the nicotine, and the body neutralise a bit. So the air he breather out with be a combination of oxygen and carbon dioxide. So the nicotine and tar content, will be diluted. Sometimes it's best to use common sense and a test of experiment, instead of believing a stupid 'mad scientist' who claims that he's right and define common sense. Pwee!

of course! Secondhand smoke is a serious health hazard causing more than 41,000 deaths per year. It can cause or make worse a wide range of damaging health effects in children and adults, including lung cancer, respiratory infections and asthma.

Yes it is. Check out this article to learn more - https://sg.theasianparent.com/passive-smoking-and-its-effect-on-children/

It is an undesired issue of inhaling second hand smoke due to neighbors who smoke in their hones

Yes it is glad singapore is more of smoke free country

Yes apparently it’s even worse than active smoking

It is bad if you stayed to inhale it for a long time

It’s really bad especially for the little ones

Actually IMO first hand, 2nd hand both as bad

yes, its worse than smoking actually