Some studies stipulate that there is a low concentration of nicotine remaining in the secondary vapor. Is it enough to cause harm or to be considered as secondary intake of nicotine is still to be proven

As far as i have read, exhaledsmokevapor from vaping have very little effect on secondarysmokersvapers. But like they said further studies need to be done. As for me personally I tried not to vape when there is someone that does not smoke around, just not to make them feel uncomfortable
Nobody knows. But you'll get a flood of opinions from all camps.
Laws banning smoking in public places and work places were justified by studies that second hand smoke probably causes illness in others. Studies that have been done so far on vaping find levels of potentially harmful substances to be so low that they are unlikely to have that effect. My view is the mean spirited attacks on vaping are to pave the way to impose taxes to replace lost tobacco taxes. Governments got greedy and overtaxed tobacco and are addicted to that money. Vaping technology is disrupting the tobacco industry the way PCs and the internet disrupted telephones, publishing, retailing, TV, etc. etc.
So...exactly how did you find this website to get your e-cig knowledge or are looking for? hummmm?Maybe you should get a sense of humor and stop using Google as a substitute for wisdom?
As I see it the main problem with a second-hand vape is a second-hand smell. It can really be annoying. Even for me, even for vaper. Recently I was in a BBQ joint, and at the next to me table some vaper produced extra strong chemical smell of raspberry. I do not like my meat with raspberries. I will not visit this joint again – I prefer air without artificial flavorings.
I vape mostly juice that produce very little if at all of smell. When trying a new flavor at home I always ask my wife about smell and according to her response I either accept or reject a flavoring.