With the improvement in technology, scientists have become efficient in detecting more pollutants in smaller concentrations present in freshwater bodies of Earth. These bodies were found to have traces of sunscreen and birth control pills to pesticides and petroleum. The lakes, streams, rivers and groundwater often are cocktail of chemicals.

Besides synthetic pollution, freshwater also contains biological waste like human sewage, excrement, fertilizers from farms and yards etc. This wastage finds its way into the sea through rivers. The contamination of the sea results in coastal zones lacking oxygen and thus having no aquatic life.

Regulation has restricted the agricultural and industrial operations from sending pollutants into rivers, streams and lakes. Technology has also helped in the formation of treatment and filtration plants that make drinking water safe for consumption. Promotion of green infrastructure in some cities is a step to curb pollution in which rain gardens and green roofs are being promoted. But the issue is still to be addressed in the developing world where there is less awareness and infrastructure (technically, economically and politically).

T.I.Sen