Iron: Important things about the amount of iron in water. Generally, the iron present in water is not dangerous for health. The amount of iron in drinking water should be 0.3 milligrams per liter (mg/L) or 0.3 parts per million (ppm). If the amount of iron in water is high, the color of water becomes red or brown. Due to excess iron content in water, it can cause skin diseases. Drinking iron-rich water can affect the liver. This can cause jaundice, hair fall, kidney related problems. Most iron comes from food, because the body cannot easily absorb iron from water. Method to find out the amount of iron in water: If there is iron in the water, then when water is poured into the sink or tub, the water turns red or brown. To find out the amount of iron in water, it is necessary to get water tested. Sodium forms water soluble components such as halide, sulphate, nitrate, carboxylate, and carbonate .