Question

The toxic elements present in natural waters and waste water is:​

Answer 1

Answer:

There are two major groups of toxic metals: (a) Mercury (Hg), Lead (Pb), Cadmium (Cd), and Arsenic (As) which are non-essential and (b) Zinc (Zn), Chromium (Cr), Copper (Cu), and Nickel (Ni) which are essential to plant and animal species growth and development.

Answer 2

Explanation:

In some places, water may be contaminated by toxics that naturally exist in the earth, such as arsenic and fluoride (a natural substance that causes brown spots on teeth and severe bone weakness). As the groundwater is used up, the risk of natural toxics grows because they are concentrated in the water that is left