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Lead has been used in a variety of products, including gasoline, paint, plumbing, batteries and cosmetics. Lead is added to paints for a few reasons. Pigments made with lead have superior hiding power. Lead paints are also very resistant to corrosion, which makes them a good choice for painting metals in highly corrosive environments. Lead paints are highly durable, which makes them an attractive option for the exterior of buildings and the markings on roads and parking lots. Similarly, lead is used as a color additive in some hair dyes.

There is evidence of humans’ use of lead since the ancient times. Perhaps the most significant was ancient Rome’s use of lead piping. In fact, the English word “plumbing” comes from the latin word plumbum, as does the symbol for lead, Pb. Ancient civilizations have also used lead for lining water storage tanks, reinforcing masonry, and in roofing. Lead’s relatively low melting point and malleability make it easy to shape into a variety of products, including ammunition, hammers and other tools, SCUBA weight belts, and fishing sinkers.

One of the largest current uses of lead is in lead-acid batteries. These batteries contain lead plates and lead oxide paste, which react with sulfuric acid to produce an electric current. Lead-acid batteries are widely used in automobiles, forklifts, golf carts, and emergency lighting. Lead has also been added to gasoline to increase the octane rating and therefore increase the amount of energy released during combustion.

Lead use has been reduced in many countries of the world. The US has banned lead paints for residential use, and leaded gasoline is also no longer in use in the US. In the EU, all electronics products containing lead have also been banned. Lead paints, however, are still produced and used in many countries, including India, China, and Malaysia. Likewise leaded gasoline is still in use in some African, South American, and Asian countries.

=Human Health=

“There is no biologic function or need for lead. There is no such thing as a ‘normal’ lead level, only that level which we are willing to tolerate.” ([|http://72.14.205.104/search?q=cache:LxShG-QXR8MJ:www.oregon.gov/DHS/ph/lead/docs/introhealtheffectsmedicalprovider.pdf+lead+in+the+body&hl=en&ct=clnk&cd=2&gl=us&client=firefox-a)]

Lead is an insidious chemical that our bodies do not need. It is very harmful as it will affect just about every system of the body, most notably the gastro-intestinal tract, the hepatic system, the nervous system, the reproductive system, and the skeletal system. Lead in most of the systems is flushed out of our bodies in a matter of months, but lead will stay in the skeletal system for decades, occasionally seeping out to wreak more havoc.

One way through which lead affects our bodies is as a non-competitive enzyme inhibitor. It bonds with the enzymes in such a way that the enzyme is misshapen. Also, it bonds very tightly, often kicking out calcium or zinc.

3Ca(protein)+Pb→Pb(protein)3+3Ca 3Zn(protein)4+4Pb→4Pb(protein)3+3Zn

The proteins in the above reactions are bonded to the lead and cannot do whatever it is they were supposed to do. Similar reactions occur with oxygen and iron.

There are some treatments for lead poisoning, but none are very effective. Basically you would be given a pill of something your body cannot metabolize but binds very strongly with lead. This is called a chelating agent. The lead that comes in contact with the chelating agent is bound to it and is then flushed out of your body with the chelatin. This will get the lead that is in the blood stream and even some in the fatty tissue, but does not address the lead that is stored within the bones.

Some of the most common symptoms of lead toxicity are slow/impaired neurological development, ADD, stunted growth, hearing loss, anemia, seizures, coma, or even death.