Chronic exposure of children to lead can result in permanent physiological impairment. In adults, it can cause irritability, poor muscle coordination, and nerve damage to the sense organs and nerves controlling the body. Surfaces coated with lead-containing paints are potential sources of exposure to lead. In April 2008, the U.S. Environmental Protection Agency (EPA) finalized new requirements that would reduce exposure to lead hazards created by renovation, repair, and painting activities, which disturb lead-based paint. On-site, inexpensive identification of lead-based paint is required. Two steps have been taken to meet this challenge. First, this paper presents a new, highly efficient method for paint collection that is based on the use of a modified wood drill bit. Second, this paper presents a novel, one-step approach for quantitatively grinding and extracting lead from paint samples for subsequent lead determination. This latter method is based on the use of a high-revolutions per minute rotor with stator to break up the paint into approximately 50 micron-size particles. Nitric acid (25%, v/v) is used to extract the lead in <3 minutes. Recoveries are consistently >95% for real-world paints, National Institute of Standards and Technology's standard reference materials, and audit samples from the American Industrial Hygiene Association's Environmental Lead Proficiency Analytical Testing Program. This quantitative extraction procedure, when paired with quantitative paint sample collection and lead determination, may enable the development of a lead paint test kit that will meet the specifications of the final EPA rule.
A 3-MeV beam of protons of 2to 150-nanoampere intensity has been used to excite X-ray emission from a wide range of biological and environmental samples-e.g., human tissue, body fluids, soil extracts, leaves, coal, fly ash, ion-exchange membranes, and proteins. The X-rays have been detected using a Si (Li) solid state detector for the elements P (Z = 15) through Pb (Z = 82). Linear response has been demonstrated for the typical elements of Pb, Cu, Zn, Co, and Mn from 5 ng to greater than 2 Mg. A lower limit of sensitivity of approximately 200 programs in the irradiated area has been attained with the more responsive elements when they are deposited on very thin substrates. The proton-induced X-ray emission technique seems especially suited to rapid and economical multielement analyses for samples of clinical and environmental interest. Numerous examples of data ob-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.