NEWS OF THE WEEK BUSINESS
LEAD DUSTUP Milwaukee, Rhode Island sue to force manufacturers to remove lead paint
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I T H I N THE SPACE OF A
week, both the City of Milwaukee and the State of Rhode Island advanced lawsuits against lead paint and pigment makers seeking mil lions of dollars for the clean up of poorly maintained, mostly inner-city housing. Widely used in residential paints prior to 1955 and banned by the federal government in 1978, lead carbonate-based paints deteriorate to a dust, threatening children's developing brains and nervous systems. New York City, St. Louis, and the County of Santa Clara, Cali fornia, are among other munici
ART
palities that have filed similar suits over the past decade. Milwaukee's suit seeks to recover costs from former lead pigment manufacturer NL Indus tries and Wisconsin paint maker Mautz Paint. Cleaning up the city's housing stocks will cost as much as $100 million, an attor ney for the city says. In Providence, R.I., a county superior court judge allowed a lawsuit brought by the state against paint and pigment mak ers in October 1999 to move to trial. T h e Rhode Island suit names not only N L Industries, but also the Lead Industries As sociation and paint companies
CONSERVATION
SCIENCE IN THE SERVICE OF ART Chemist helps unveil original vibrancy of a 17th century painting
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o DEMYSTIFY T H E w i z
ardry that takes place behind the scenes in its con servation division, the National Gallery of Art in Washington, D.C., last week took journalists on a tour of its labs. This was the first of what will become an annual event. In the scientific research lab, chemist Barbara H. Berrie, a conservation scientist, ex plained how science helped to determine that the brown paint in the oil painting "St. Sebast ian" was not applied by the artist, Tanzio da Varallo. Tanzio painted this picture sometime in the 1620s. But scanning elec HTTP://PUBS.ACS.ORG/CEN
tron microscopy of a scraping revealed that the brown paint was cadmium orange, a modern pigment. Conservator Susanna Ρ Griswold removed the brown paint, which exposed a layer of green paint seen in the drapery across the saint's lap (bottom, left). Now the question was: Should the green paint also be removed? Berrie took a microscopic sample from the drapery area that disclosed in cross section a layer of varnish between the green paint and an underlying yellow paint layer (top). Using polarized light microscopy, she identified the green paint as a
including DuPont, Glidden, and Sherwin-Williams. Responding to the Rhode Island suit, paint makers' attor ney Donald E. Scott points out that "in the early 1950s, the industry sponsored medical research that helped to define and publicize the health risk to chil dren from deteriorated, poorly maintained interior lead paint. The companies all voluntarily stopped marketing interior leadbased paint decades ago and pro vided product warnings." It is important to put these lawsuits in perspective, says N L Industries spokesman Alan Wheat, who notes that, "of the 40 to 50 lawsuits against the for mer manufacturers of lead pig ment that have been concluded, the companies have not lost or settled a single case. The prob lem is not a manufacturing prob lem; it is a maintenance prob lem."—MARC REISCH
WARNING Peeling lead-based paint is hazardous to children's health.
mixture of copper acetate and calcium carbonate. The inter vening varnish layer indicated to her that the green paint was the result of a previous restoration and could be removed. Removal of the green paint revealed not only a pulsating yel low color but the sensuous folds of the drapery as Tanzio painted it (bottom, right). Using X-ray powder diffraction, Berrie iden tified the yellow pigment as lead tin oxide. — LOIS EMBER
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