I used to post that quote here too. It's addressing the fact that there is no such person as "the public" and thus we cannot reffer to his "rights".
To extend it, one could argue that there is no such thing as "public health", the only thing that really exists is statistics and they have no rights as a person either.
However the discussion was about physical person rights like in mine vs. yours. Ayn doesn't tell us whom's rights shall prevail.
She does, but not in the context of second hand smoke/vapor....
"If some men are entitled by right to the products of the work of others, it means that those others are deprived of rights and condemned to slave labor.
Any alleged “right” of one man, which necessitates the violation of the rights of another, is not and cannot be a right.
No man can have a right to impose an unchosen obligation, an unrewarded duty or an involuntary servitude on another man. There can be no such thing as “the right to enslave.”"
and:
"A right cannot be violated except by physical force. One man cannot deprive another of his life, nor enslave him, nor forbid him to pursue his happiness, except by using force against him. Whenever a man is made to act without his own free, personal, individual, voluntary consent—his right has been violated.
Therefore, we can draw a clear-cut division between the rights of one man and those of another. It is an objective division—not subject to differences of opinion, nor to majority decision, nor to the arbitrary decree of society. No man has the right to initiate the use of physical force against another man."
And:
"There is no such thing as “a right to a job”—there is only the right of free trade, that is: a man’s right to take a job if another man chooses to hire him. There is no “right to a home,” only the right of free trade: the right to build a home or to buy it. There are no “rights to a ‘fair’ wage or a ‘fair’ price” if no one chooses to pay it, to hire a man or to buy his product. There are no “rights of consumers” to milk, shoes, movies or champagne if no producers choose to manufacture such items (there is only the right to manufacture them oneself). There are no “rights” of special groups, there are no “rights of farmers, of workers, of businessmen, of employees, of employers, of the old, of the young, of the unborn.” There are only the Rights of Man—rights possessed by every individual man and by all men as individuals."
On ecology in general:
"City smog and filthy rivers are not good for men(though they are not the kind of danger that the ecological panic-mongers proclaim them to be). This is a scientific, technological problem--not a political one--and it can be solved only by technology. Even if smog were a risk to human life, we must remember that life in nature, without technology, is wholesale death."
and a few more passages that may interest some:
Ayn Rand on Environment