7 Biological pollutants
Biological pollutants are organisms that may be harmful to other forms of life, but they have to be ingested to have any effect. The most usual form of transmission is the faecal–oral route, in which faecal matter from one human being finds its way into another. This can happen through the ingestion of faecally contaminated water or food. Alternatively, sometimes pathogenic organisms can be consumed through eating contaminated undercooked food, as in the case of certain strains of Escherichia coli.
The effects of the different organisms are varied, and can be more easily ascertained through sources such as the WHO or local health protection agencies. However, in this subsection I will describe the characteristics of the main water-borne pollutants, namely:
- pathogenic bacteria
- coliforms
- faecal streptococci
- Clostridium perfringens
- viruses
- protozoa
- helminths
- other biological pollutants.