Lead-based paint production

The toxicology of household products is fascinating because it deals with products that we are all familiar with and because so many different kinds of products are involved. A typical home may contain cleaning products, cosmetics and personal care products, paints, medications, pesticides, fuels, and various solvents. Thermometers and thermostats may contain mercury, a well-known toxicant. Older homes were often painted with a lead-based paint, which if consumed causes serious developmental effects. Building materials may contain toxic solvents that are released into the home. The toxicity and ingredients of household products vary widely, but highly toxic products are found in most homes (Table 18.1). 

EXPOSURE ROUTES leaded gasoline combustion combustion of solid waste, coal, and oils emissions from iron and steel production lead smelters tobacco smoke food and soil lead-based paints flaking paint paint chips weathered paint powder drinking water pipes, solder, and fixtures lead smelting and refining industries steel and iron factories gasoline stations battery manufacturing plants... 

The Administrator, in consultation with the Chairman of the Consumer Product Safety Commission, shall develop information to be distributed by retailers of home improvement products to provide consumers with practical information related to the hazards of renovation and remodeling where lead-based paint may be present. 

Not later than 30 months after October 28, 1992, the President shall, after notice and opportunity for comment, establish by rule appropriate criteria, testing protocols, and performance characteristics as are necessary to ensure, to the greatest extent possible and consistent with the purposes and policy of this subchapter, that lead-based paint hazard evaluation and reduction products introduced into commerce after a period specified in the rule are effective for the intended use described by the manufacturer. The rule shall identify the types or classes of products that are subject to such rule. The President, in implementation of the rule, shall, to the maximum extent possible, utilize independent testing laboratories, as appropriate, and consult with such entities and others in developing the rules. The President may delegate the authorities under this subsection to the Environmental Protection Agency or the Secretary of Commerce or such other appropriate agency. 

Over the past 30 years, many lead-based products have disappeared from use or the use has been greatly diminished. These products include lead-based paints, lead-based anti-knock compounds for automobiles, lead glazes for pottery, lead sealants for wine battles, solder for sealing the seams of steel cans, automobile body solder, solders for potable water systems, solder for sealing copper radiators, chemical tank linings, lead pipes, lead-based metal bearings, lead sealants such as for drain pipes, power and electrical cable sheathing, and ammunition. 

Lead acetate (1885) n. Pb(C2H302)2 3H20. Crystalline salt, soluble in water and used in the manufacture of lead pigments also used in production of varnishes. Kirk-Othmer encyclopedia of chemical technology pig-ments-powders. John Wiley and Sons, New York, 1996. Gooch JW (1993) Lead based paint handbook. Plenum Press, New York. 

Toys and furniture sold before 1976 may have been painted with lead-based paint. Stripping old furniture can create very high levels of lead dust. Imported toys are still occasionally identified and recalled by the U. S. Consumer Product Safety Commission (CPSC) because they contain dangerous levels of lead paint. Playground equipment may be painted with lead-based paint. Such equipment in a number of city parks around the United States has been recently found to present a hazard to young children. For information on product safety and recalls, contact the CPSC, listed in Appendix B under Product Safety. 

Encapsulants generally refer to specially designed coatings that are painted over a lead-based painted surface to cover up the paint and make it inaccessible. There are also encapsulant products that can be bonded to lead-painted surfaces with an adhesive to accomplish the same thing. 

Fast forward to the present day and the hazards and uses of lead are heavily regulated by OSHA and the EPA to protect both employees and the environment. The Consumer Products Safety Commission has also lobbied Congress to ban certain products from being imported that do not meet the US. standards for lead safety to protect consumers. Many products imported from China used lead-based paint in the manufacturing process, which led to an immediate ban on certain children s toys including all-terrain vehicles and smaller motorcycles built by Honda (Motorcycle, com, 2009). The goal of the new ban was to protect children under twelve that could be exposed to lead. 

Although the Consumer Product Safety Commission (CPSC) banned the residential use of lead-based paint in 1978, millions of children remain at risk for exposure to lead from deteriorating paint in older homes. Lead poisoning is especially harmful to children under the age of 5 years because it interferes with growth and development and it has been shown to lower IQ. Symptoms of chronic exposure to lead include diminished appetite, nausea, malaise, and convulsions. Blood lead level fBLL), expressed as micrograms per deciliter (p.g/dL), is used to monitor the effect of chronic exposure. A BLL < 10 p.g/dL is considered normal a BLL > 45 xg/dL requires medical and environmental intervention. At high levels (>70 p.g/dL), lead can cause seizures, coma, and death. 

The inhibitive mechanism of the red lead found in lead-based paint (LBP) is complex. Lead pigments may be thought of as indirect inhibitors because, although they themselves are not inhibitive, they undergo a reaction with select resin systems and this reaction can form by-products that are active inhibitors [23]. 

In the past, the health and safety concerns with lead poisoning have focused on lead-based paint and lead in gasoline. However, the increasing quantity of scrap electronic products disposed into landfills has raised the question of the environmental impact of this source of lead. Studies in 1991 by Allenby, et al. [2] examined the potential for replacing lead-based solder and concluded that there were no viable alternatives at that time. They also suggested that the total environmental impact of lead and its alternatives, from mining, through manufacture, use, and end-of-life should be considered. 

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