Chapter 3 - Heavy metal contamination in the river ecosystem

Abstract

Rivers are the main source of water throughout the world. However, increase in urbanization has declined the quality of the river water and it has become almost unusable for domestic or bathing purpose. In the modern age, contamination of heavy metals in river ecosystem has become the biggest challenge for the humanity. As heavy metals are toxic and nonbiodegradable in nature, they can cause serious threat to both flora and fauna even when present at very low concentration. Sources of heavy metals in the rivers may be anthropogenic and natural. However, anthropogenic activities (especially discharges of untreated industrial effluents) are mostly accountable for the heavy metal contamination in river ecosystems. They enter into the river ecosystem and may affect the aquatic organisms via bioaccumulation and/or biomagnifications. Moreover, these toxic metals can reach inside the bodies of humans and animals through food chain and cause serious health problems. In this chapter, critical discussion will be carried out on the sources and contamination of heavy metals in river ecosystem along with their adverse impact on both flora and fauna. Some preventive steps will also be discussed to maintain the ecological health of the river ecosystems.