Can we conceive of something being a psychological pollutant, in the same way we conceive of physiological pollutants?
Consider for example a clothing advert that features extremely skinny women in expensive clothing (as they often do). It seems clear that this is harmful to the consumer in a number of ways. Most clearly, it is damaging to women, who are pressured to meet unrealistic and unhealthy standards for appearance.
Being that one cannot isolate oneself from these advertisements (you can shut off your TV but you can't avoid the big billboards on city streets), does it not make sense to outlaw such billboards on the basis that they are unavoidable psychological pollutants?
And if not, is it only because it's harder for us to quantify and locate psychological damage than it is to locate physiological damage?
Freedom of expression is a very great good and so justifies allowing considerable (though not unlimited) psychological pollution. There may not be such a potent compensating good in the case of physiological pollution. It may be that a policy of additional legal restriction on psychological pollution would carry a greater moral cost than does the current legal restrictions on physiological pollution.