Heavy Metals Source Permissible level (mg/l)
Lead (Pb) Lead acid batteries, paints, E-waste, Smelting operations, coal-based thermal power plants, ceramics, bangle industry, canned fruit juices, 0.1
Mercury (Hg) Chloro-alkali plants, thermal power plants, fluorescent lamps, hospital waste (damaged thermometers, barometers, sphygmomanometers), electrical appliances etc. 0.01
Cadmium (Cd) Zinc smelting, waste batteries, e-waste, paint sludge, incinerations and fuel combustion, pharmaceutical and recreational drugs, nuclear plant 0.06
Chromium (Cr) Electroplating processes, mines, mineral sources 0.05
Arsenic (As) Pesticides, herbicides, insecticides, 0.02