Since the discovery of cadmium in the early 20th century, cadmium production has increased year by year. A considerable amount of cadmium is discharged into the environment through exhaust gas, waste water, and waste residues, and the water pollution caused by cadmium ions has caused great harm to human health. Cadmium occurs naturally in zinc, in lead and copper ores, in coal and other fossil fuels, in shales and is released during volcanic action. These deposits can serve as sources to ground and surface waters, especially when in contact with low total dissolved solids (TDS) and acidic waters. In industry, cadmium is mainly used for electroplating of steel, iron, copper, brass and other metals due to its strong corrosion resistance to alkaline substances. In addition, cadmium is also the main material for manufacturing batteries. Cadmium is found in drinking water supplies as a result of deterioration of galvanized plumbing, along with industrial waste contamination, or surface water contamination by certain fertilizers. Drinking water with high cadmium ions for a long time, cadmium ions will be deposited in the human bones, hinder the body's absorption of calcium, resulting in a large loss of calcium ions in the body, causing osteoporosis, fractures, bone pain, serious or even cause cancer. Chronic cadmium poisoning mainly affects the kidney, the most typical ion is the famous public disease in Japan-Itai-Itai Disease. Therefore, many countries regulate the concentration of cadmium ions in drinking water. The US EPA has established a Maximum Contaminant Level (MCL) of 0.005 milligrams per liter (mg/L) for cadmium in drinking water. WHO established a guideline of 0.003 mg/L for life time consumption.