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Industrial

What are the Industrial Sources of Lead?
Industries that emit lead particles into the environment include lead mining, lead smelting, coal burning power plants, manufacturers of batteries, glass, pottery, dishes and china products. The EPA monitors the emissions of these industries under the Clean Air Act. Other federal and state legislation determine the legal amount of lead emissions under their jurisdictions.

How is Lead Produced?
Lead is an element found in nature. The two main sources for industrial lead are mining lead ore from deposits in the earth and recycling lead from unused materials. Both require a smelting process to extract the lead from composite materials and a refinement process to render the lead into an industrial grade raw material. Since the mining of lead generally occurs underground, the primary emission problem comes from the smelting and refinement processes. The U.S. remains one of the world’s largest producers of lead ore. However, much of the smelting and refinement processing now takes place overseas.1

Why is the Power Industry a Source of Lead?
Generating about 39.6 percent of the country’s electricity needs, coal burning power plants are the largest provider of energy in the U.S.2 To accomplish this 450 facilities operate about 1,200 coal-fired generators which emit 84 of the 187 hazardous air pollutants identified by the EPA.3 Included in these pollutants are lead contaminated particles. Although people living near coal-fired power plants have the greatest health risks, leaded pollutants can travel hundreds of miles where the particles get deposit onto the yards, gardens, parks, playgrounds and schoolyards where susceptible children live and play.

Why is the Battery Industry a Source of Lead?
Since their invention in 1859, lead-acid batteries have been widely used around the world. According to the U.S. Geological Survey, the battery industry consumes about 86% of the lead in the U.S.4 Fortunately, lead-acid batteries are one of the most highly recycled consumer products with more than 98% being reused. According to the U.S. Battery Council, a typical new lead-acid battery contains between 60 and 80% recycled lead and plastic. 5

Battery manufacturing and battery recycling are both multi-step processes that can potentially result in large amounts of lead emissions. However modern filtering technologies are able to capture most of these emissions. The EPA is reporting lead emission reductions for manufacturing processes using fabric filters is over 99% and more than 85% reduction for other manufacturing methods using scrubbers. 6

Why is the Glass Industry a Source of Lead?
Adding lead to the glass making process generates favorable qualities including density, durability, refractive index and factors that make it easier to cut, polish and decorate finished products. These features make leaded glass particularly useful when manufacturing optical products such as binoculars, microscopes, telescopes as well as lead crystals used in cathode ray tubes, televisions, computers, and video game screens.

Why are Dishware, Pottery, & Ceramics Manufacturers a Source of Lead?
Adding lead to glazes applied to clay-based ceramic products heightens the decorative color and improves durability for these items subject to repeated cleanings. Glazes are often highly soluble which permits the lead to leach into the food or liquid held within the containers. Because of this, the ceramics industry has largely switched away from lead glazes. As of 1971, the FDA has set guidelines for the permissible amount of lead leaching that can occur from these products. However, products made in other countries may not comply with these regulations.

References
  1. Environmental Impacts of Mining and Smelting, Occupational Knowledge International. n.p. n.d. Web. 20 Aug. 2014. http://www.okinternational.org/mining
  2. Electric Power Monthly, U.S. Energy Information Administration. n.p. 28 Jul. 2014. Web. 20 Aug. 2014. http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01
  3. Emissions of Hazardous Air Pollutants from Coal-Fired Power Plants, Environmental Health & Engineering, Inc. for The American Lung Association. EH&E. 7 Mar. 2011. Web. 20 Aug. 2014. http://www.lung.org/assets/documents/healthy-air/coal-fired-plant-hazards.pdf
  4. Mineral Commodity Summaries, U.S. Geological Survey. n.p. Jan. 2013. Web. 20 Aug. 2014. http://minerals.usgs.gov/minerals/pubs/commodity/lead/mcs-2013-lead.pdf
  5. Battery Recycling, Battery Council International. n.p. n.d. Web. 21 Aug 2014. http://batterycouncil.org/?page=Battery_Recycling
  6. Locating And Estimating Air Emissions From Sources of Lead and Lead Compounds, Office of Air Quality Planning and Standards Office of Air and Radiation, U.S. Environmental Protection Agency. n.p. May 1998. Web. 20 Aug. 2014. http://www.epa.gov/ttnchie1/le/lead.pdf