Lead is a toxic metal
· Even at low levels, lead may cause a range of health effects including behavioral problems and learning disabilities.
· Children six years old and under are most at risk because this is when the brain is developing.
· Adults who drink this water over many years could develop kidney problems or high blood pressure.
· The primary source of lead exposure for most children is lead-based paint in older homes. Lead in drinking water can add to that exposure.
· Lead poisoning affects over 100 million people in India, especially children, pregnant women and workers in certain occupations.
· Lead level in the blood should not exceed 10 micrograms/dL (mcg/dL).
· Major sources of lead include drinking water, contaminated soil, petrol emissions, household dust, battery recycling, silver refining, paints, pigments, printing presses, ceramic pottery glazes, cosmetics, colours (including kumkum, sindoor, spices and Holi colours), children's toys, plant foods and adulterated traditional medicines.
· Diet high or low in protein, high in fat, low in calcium, iron and zinc can also lead levels in the blood
· Lead in drinking water is absorbed more completely than lead in food and may account for more than 50% of the lead that is ingested by children
· Municipal water supplies are controlled and regulated to prevent contamination at the source. However, once the water reaches the home, it is rarely regulated, tested, or treated.
· Ground water also may be high in lead contents.
· EPA action level for lead in water is 15 parts per billion
· Most lead-contamination of household water is caused by copper plumbing that is joined with lead solder
· Lead pipes may contribute to lead-contamination, but lead plumbing usually is old enough to have its inner surface coated with mineral deposits, which prevent leaching of lead into the water supply.
· Lead contamination can also occur due to storage cisterns, sources of water that are outside the municipal water districts, and aging water coolers and water heaters, particularly in areas where the water has a relatively low pH
· Acidity and elevated temperature increase the ability of the water to leach lead from the solder or pipes, as does standing in the pipes for extended periods of time (overnight).
· Removal of the source of lead is the most reliable way to eliminate water-based exposure to lead.
· Reverse-osmosis filters, ion exchange and distillation are effective in removing lead.
· Most commonly available home filters (glass fiber and carbon) usually include packaging material that specifies that they do not efficiently remove heavy metals.
· Heating or boiling your water will not remove lead. Because some of the water evaporates during the boiling process, the lead concentration of the water can actually increase slightly as the water is boiled.
· Chlorination and iodine also does not remove lead.
· Water to be used for cooking or drinking should come from the cold tap because hot water is more able to leach lead from the pipes.
· In addition, the water should be run for some time before it is collected; this flushes the water that has a higher lead content (caused by standing in the pipes) down the drain.