What is one potential environmental concern associated with effluent discharge?

Effluent discharge refers to the release of treated or untreated wastewater into natural water bodies. One significant environmental concern related to this process is that it can introduce harmful contaminants into natural waters. This can occur through various pathways, including the presence of heavy metals, pathogens, pharmaceuticals, and other toxic substances that may not be fully removed during treatment processes.

When these contaminants enter aquatic ecosystems, they can adversely affect water quality and aquatic life. For example, heavy metals can accumulate in the tissues of organisms, leading to bioaccumulation and biomagnification through the food chain. This poses risks not only to wildlife but also to human health if contaminated water or fish are consumed.

In contrast to this concern, the other options suggest potential benefits or neutral effects of effluent discharge, which are not consistent with the established environmental risks associated with discharging wastewater. Therefore, the choice highlighting the introduction of harmful contaminants is the most accurate reflection of a fundamental environmental issue regarding effluent discharge.