(wikipedia)
Visual pollution is the term given to unattractive and man-made visual elements of a vista, a landscape, or any other thing that a person does not feel comfortable to look at. Visual pollution is an aesthetic issue, referring to the impacts of pollution that impair one's ability to enjoy a vista or view. The term is used broadly to cover visibility, limits on the ability to view distant objects, as well as the more subjective issue of visual clutter. In other words, pollution is the contamination of the environment as a result of human activities. The term pollution refers primarily to the fouling of air, water, and land by wastes (see air pollution; water pollution; solid waste). In recent years it has come to signify a wider range of disruptions to environmental quality. Thus litter, billboards, and auto junkyards are said to constitute visual pollution; noise excessive enough to cause psychological or physical damage is considered noise pollution; and waste heat that alters local climate or affects fish populations in rivers is designated thermal pollution. It´s other reference is to "marketing advertisements".