Explanation

Industrial discharge is waste released directly into rivers, lakes, and oceans from factories. This waste often contains harmful chemicals, heavy metals, and toxins. These pollutants poison water and kill fish, plants, and other aquatic life.

Factories dump waste water containing dyes, acids, pesticides, and other dangerous substances into nearby water bodies. Even small amounts of industrial chemicals can harm entire ecosystems. Fish that survive in polluted water can become unsafe for humans to eat.

Soil erosion, deforestation, and air pollution can affect water quality indirectly over time. However, industrial discharge puts pollutants straight into the water immediately. This makes it the most direct and harmful primary source of aquatic pollution.