Pollution of Crowding : When a large number of people live in a limited space, it causes crowding. Studies indicate that due to crowding, there were incidents of sickness among animals. Studies conducted on human being regarding density affects the quality of individual behaviour as well as social behaviour. For example : When 7 to 8 people lie in a 10'x 10' room, it affects on their interpersonal relations. They become more aggressive, less at truistic, less helping and regressive.
Crowding is a big problem. According to some researchers, the term crowding is used in reference to the feeling of crampedness. Some people do not consider crowding in terms of physical density. Therefore, it is necessary to use two different terms, when a large number of people are present in one place, that is density and due to very close contact the feeling of pushing and pulling one another is known as crowding. Density refers to actual number of people per square foot, while crowding is the subjective feeling of being too close to one - another. In density, there is a feeling of common belongingness while in crowding, the feeling is too less.
Studies regarding crowding show that it has negative effect on task performance, personality and interpersonal relationship and physical and mental health of the person. The common effects of crowding are obstructions in goal achievement, undesirable interference.