(a) Two main types of environmental pollution are:
(i) Air pollution
(ii) water pollution
Three causes of water pollution include:
(I) The release of disease-producing (pathogenic) bacteria and viruses (biological pollution diseases
(ii) Undesirable ions and compounds in solution (chemical pollution) into water thereby changing its colour, taste and/or smell
(iii) Oil spillage - the bursting of oil pipes results in oil spillage into water thereby changing the colour, taste and smell of the water.
(b) Three effects of pollution on man are:
(i) Atmospheric pollution, which may be caused by fog reduces visibility. This poses a serious danger to motorists and pilots
(ii) Pollutants may have adverse psychological effects on man and animals e.g discomfort, chronic diseases, such as lung cancer and asthma, impairment of growth and death
(iii) Some pollutants are toxic and can kill plants e.g sulfur dioxide and hydrogen fluoride are toxic to plants from which man gets his food.