[{"from": "human", "value": "Describe this molecule. [Pb]"}, {"from": "gpt", "value": "The molecule is a naturally occurring bluish-gray metal found in small amounts in the earth's crust. Lead can be found in all parts of our environment. Much of it comes from human activities including burning fossil fuels, mining, and manufacturing. Lead has many different uses. It is used in the production of batteries, ammunition, metal products (solder and pipes), and devices to shield X-rays. Because of health concerns, lead from gasoline, paints and ceramic products, caulking, and pipe solder has been dramatically reduced in recent years.*CDC has updated its recommendations on children\u2019s blood lead levels. Experts now use an upper reference level value of 97.5% of the population distribution for children\u2019s blood lead. In 2012-2015 that value is 5 micrograms per deciliter (\u00b5g/dL) to identify children with blood lead levels that are much higher than most children\u2019s levels. The information on this page refers to CDC\u2019s previous \u201cblood lead level of concern\u201d of 10 \u00b5g/dL. This information will be updated in future ToxProfile and ToxFAQ editions. To learn more about CDC\u2019s updated recommendations on children\u2019s blood lead levels, please visit:http://www.cdc.gov/nceh/lead/ACCLPP/blood_lead_levels.htm."}]