What are the components of domestic sewage and industrial effluents?

(N/A) Domestic sewage, originating from homes and hospitals, contains organic waste, nutrients, and a high concentration of pathogenic microorganisms. Its disposal into water bodies without proper treatment can lead to the outbreak of serious waterborne diseases such as dysentery, typhoid, jaundice, and cholera.
In contrast, industrial effluents from sectors like petroleum, paper manufacturing, metal extraction, and chemical production contain toxic substances. These notably include heavy metals (defined as elements with density $ > 5 \,g/cm^3 $, such as mercury, cadmium, copper, and lead) and a variety of hazardous organic compounds.