Know the Chemistry

• Paint removers are chemicals that dissolve paint or destroy its bond with the surface it coats. The easiest way to dissolve paint is to slather the painted surface with solvent-based compounds. Traditional solvents include hydrocarbons like methylene chloride, acetone, toluene, methanol, N-methylpyrrolidone and various dibasic esters. Caustic alkali compounds attack the bond, essentially turning it into soap from the inside out; their main ingredients are lye, caustic soda or caustic ash. New "water-based" stripping techniques use biochemical strippers that may contain terpenes (naturally-occurring hydrocarbons) from pine or citrus, lactic or citric acids, corn sugars and soy oil. They are often fortified with a solvent, often N-methyl-2-pyrrolidone, that helps break the molecular bonds of the paint. The challenge in all strippers is to control the production of toxic vapors, called volatile organic compounds (VOC), which are produced by the chemical reaction that dissolves or loosens paint.
  
  

Choose Alternatives When Possible

• Several methods of paint removal have been developed as faster, low-VOC alternatives to chemical strippers. The pre-chemical method, using sandpaper or a wire brush, creates dust and damages wood. If the dust can be contained and the wood surface is not historic or fragile, it is an environmentally friendly option. The other non-chemical method--heat--requires some skill. It uses a propane torch or infrared gun to literally burn paint off. As with sanding and scraping, lead paints can pose a disposal problem with this method and heat guns have been implicated in a number of house fires where renovation work utilized this method. Waste from these methods, as from chemical strippers, should be disposed of according to regulations established in local hazardous waste programs.
  
  

Proceed With Caution

• In 1999, the U.S. government began regulating the amount of VOC's that could be produced by paint and other coating products. The problem with modern "low-VOC" and "eco-friendly" compounds is that most of them still produce toxic "off-gassing." The "greenest" preparations often require more chemicals to accomplish the same degree of paint removal as the more toxic chemicals. The use of any of these methods in an environmentally sensitive way lies in the choice of the proper method for the job, containment procedures for chemicals and waste and environmentally safe disposal. Early paints contained poisons like lead and asbestos along with more benign substances like milk. Choose strippers that are made specifically for the type of paint you need to remove---they will work faster and some strippers will actually isolate or neutralize toxins, making disposal easier. Covering stripper with plastic wrap helps control off-gassing and keeps strippers wet longer, focusing chemical action on paint. Limit the use of abrasives and heat guns to situations where strippers don't work and insist on experienced practitioners to do the work. A community development, university extension or county environmental agent may be able to help with paint analysis and recommendations.