Which human activity has the most negative impact on water quality

There are many human activities that pollute water, but I'd say that the industry is one of the worst. Many industries pour their waste, that if often toxic into water sources such as rivers or even the ocean. This waste not only harms wildlife of all sorts (animals, fish,plants, etc.) but also causes illness in humans.

Sun is explosive itself spread 9 planets.earth is 3rd explosive in the solar system about 500 hundred million years ago . first earth became ice age and freezing climate.centre of earth magma. north zone is artic . south is anatric