The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppb,40 ppb,100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to high concentration of

Options

A. fluoride
B. lead
C. nitrate
D. iron

Answer

C

Explanation

In drinking water, maximum permissible concen tration (tolerable limits) of different chemicals are Fluoride (1 ppm), lead (50 ppb), nitrate (50 ppm) and iron (0.2 ppm). As the given sample of water contain higher concentration of nitrate ions (100 ppm) than the permissible limit of 50 ppm, therefore, given sample of water is unsuitable for drinking. Excess of nitrate ions causes a disease called methemoglobinemia