Methods of Targeting Animal Sources of Fecal Pollution in Water

Abstract

The determination of fecal pollution sources in waters is essential in the management of catchments. Although traditional microbial water analyses using indicator microorganisms have been used for water-health management for more than a century, it is known that they cannot provide information about the origin of fecal pollution. The distinction between anthropogenic and non-anthropogenic (animal) fecal pollution in water would greatly support assessment of health risks based on knowledge of the host-specificity of many pathogens. For example, human sewage could constitute a higher health risk to humans than wastewater of animal origin. However, there are some exceptions because some pathogens can infect and cause clinical disease in both humans and animals. Therefore, the fecal pollution source assessment could support different water management strategies, treatment measures and policies to prevent or decrease fecal inputs in water and remediation at the source. In this chapter, proposed chemical and biological MST indicators for the determination of animal fecal sources are discussed. The biological indicators are grouped based on the phylogenetic description of the proposed target (eukarya, bacteria, and virus). A comprehensive description for each proposed target is provided and the developed methodologies employed are presented. Emphasis is placed on the validation and applicability of each proposed method and animal-MST indicator. New molecular approaches for animal-NST targets based on metagenomics are also presented. Finally, MST assay implementation, their contribution to the assessment of maximum fecal load of water bodies and their relationship to traditional microbial indicators and water-borne pathogens is examined.