Medical researchers have already long tested chemicals including those in tobacco ingredients and cigarette smoke. They recognize that the chemicals in the tobacco combination are inherently dangerous. Tobacco chemicals are inherently dangerous, so total solutions, not partial ones, are the only scientifically valid ones. Even children know better than politicians on this point. Some schools have as a classroom science exercise, an experiment of pouring two different colored liquids into one container.
Any child can see almost instantly that they mix.
So it is unconstitutional. When the government could not prove X accurate from a science, engineering, or logic point of view, the law was struck down by the courts. As segregation does not end the hazard, it is obvious on its face that the segregation concept is flawed. Alford is particularly relevant. It was a case concerning no-smoking sections.