An MIT physicist and colleagues have invented a device that makes it easier to detect lead in painted surfaces-a known health risk to children. The hand-held XL Spectrum Analyzer and its developers, led by Professor Lee Grodzins of the Department of Physics and the Laboratory for Nuclear Science, recently received a 1995 R&D 100 Award. These awards honor the 100 most technologically significant new products and processes (See the November 8 Tech Talk for stories on three other MIT groups who won 1995 R&D 100 Awards).
Some 60 million homes in the United States still have lead paint in them. When that paint ages, chips and wears, the airborne dust it produces can be ingested and children, in particular, can be poisoned. It is estimated that more than three million children in the US already have elevated levels of lead. So it is important to know whether-and where-there's lead in a given home.
The XL has a number of advantages over other devices on the market to detect lead, said Professor Grodzins, who founded Niton, Corp., the company that produces the device. "Our goal was to make an instrument that is smaller than others (to fit into elaborate window wells, etc.); lighter than others (a considerable benefit when testing ceilings), and more reliable than others." At $12,000, the XL is also one of the least expensive devices of its kind. It is now being used by independent lead inspectors, environmental firms and government agencies.
The XL detects lead by emitting X-rays that excite atoms near the surface of the wall, Professor Grodzins said. These atoms emit radiation that is distinctive for each element present. The XL has been optimized to detect the radiation that is distinctive to lead. If there is lead present, the monitor on the XL shows the amount. It takes only three to four seconds for the device to detect lead on surface paint, 15 to 20 seconds if it is buried.
Professor Grodzins, who has been at the Institute for 35 years, noted that "my research and teaching at MIT were the essential background for inventing this device." Recently he received his fourth patent for technology used in the XL.
He stressed, however, that Niton employees, many of whom are MIT graduates, helped turn his ideas into a working device. For example, Charles Parsons, MIT PhD '92 and head of research and development at Niton, designed the electronics and software for the XL. Stephen Shefsky '88 and Peter Mao '94 also played important roles. The device was brought to market by Ethel Grodzins Romm, Niton's president and CEO and Professor Grodzins' sister.
The contributions of Paul A. Scagnetti, a graduate student in mechanical engineering, were inadvertently omitted from a November 8 Tech Talk about MIT winners of 1995 R&D 100 Awards. Mr. Scagnetti helped develop the award-winning Hydroguide, a devide that makes machine tools faster and more accurate.
A version of this article appeared in MIT Tech Talk on December 13, 1995.