It will become clear that the agencies giving rise to pollution are extremely diverse and can be found everywhere Three broad categories of material pollution can be distinguished. These are: native or natural, not caused by man; generated by man but not created by him; and increasing pollution caused by mans synthetic activities• It will become clear that the agencies giving rise to pollution are extremely diverse and can be found everywhere. • Three broad categories of material pollution can be distinguished. These are: native or natural, not caused by man; generated by man but not created by him; and increasing pollution caused by man’s synthetic activities