Which of the following is included in the definition of conventional pollutants?

The definition of conventional pollutants generally includes those contaminants that have established and recognized treatment processes in wastewater management, and are commonly found in both urban and industrial discharges. Fecal coliform is a specific type of bacteria used as an indicator of water quality, particularly in relation to sanitary conditions and potential pathogen contamination. This pollutant type is significant in assessing the health of water bodies, especially concerning human health risks associated with the presence of fecal matter.

Conventional pollutants typically focus on substances that can be commonly controlled and regulated via conventional methods. While other options mentioned may have environmental impacts, they do not fit the conventional pollutant classification as clearly as fecal coliform does. Chemical fertilizers, for instance, while harmful to ecosystems, generally fall under the category of non-conventional pollutants or nutrient pollutants, and heavy oil is more associated with industrial or oil-related discharges rather than conventional wastewater treatment processes. Lead is a toxic metal and classified differently given its hazardous nature. Fecal coliform directly aligns with the established indicators of water pollution under typical regulatory frameworks, making it the correct choice in this context.