EPA interim final report on WTC background study, April 2003

NYC 9/11 Public Portal Document

Certificate 2581 http://patapsco.iiist.gov/srmcatalog.,7view_cert2gif.cftn?certificate=2581

The overall direction and coordination of he technical measurements leading to certification of this SRM were performedbyJR.DeVoe,PA. Pella, and RD. Watters, Jr. of he NIST Analytical Chemistry Division.

Statistical consultation was providedby SD. Leigh of the NIST Statistical Engineering Division.

Partial financial support for he development of this SRM was provided by the U.S. Environmental Protection Agency (EPA) under the direction of project managers SD. Harper andMR. Beard of the EPA Office of Research and Development, National Exposure Research Laboratory, ResearchTriangle Park; NC.

COLLECTION,PREPARATION, AND ANALYSIS

Collection: The paint material for this SRM was collected primarily in North Carolina from various interior wall surfaces of old housing which, for the most part, were painted prior to 1945. The material was collected under the direction of the Research Triangle Institute and the U.S. Environmental Protection Agency. Collection of paint by dry scraping and its initial evaluation for use as SRM 2581 were performed by ID. Neefbs, E.E. Williams, and DR. Binstock, of the Research Triangle Institute, Research Triangle Park, NC, under the leadership ofW.F. Gutknecht.

Preparation: The largest pieces of debris and foreign material were first removedby hand. Next, the material was coarsely (hipped in a large-c^acity blender fitted with a stainless steel blade. The material was than further ground in small batches in a ball mill. Each batch was sieved and the fraction that did not pass a 100 pm (#141^ sieve was returned for further grinding with a fresh charge of coarse paint material All material of a size less han 100 pm was combined and blended as a single batchbefbre beir^ bottled in 35 g units.

Analysis: Certification analysis by ID-ICPMS was performed by E.S. Beary and K.E. Murphy of the NIST Anal^cal Chemistry Division. X-ray fluorescence homogeneity analysis was performed by A J. Marlow and PA. Pella and inductively cotjpled plasma-optical emission spectrometric (ICP-OES) analysis was performed by LJ. Wood of the NIST Analytical Chemistry Division.

The ICP-OES analysis data given in Table 1 provide information on he concentrations of major constituents other then lead in the material. These values listed are not certified, but are given coily to provide additional information on the matrix.

bistructioiB for Drying: Samples of this SRM should be dried in an air atmosphere at 105 "C for 2 h At NIST, loss on during according to his procedure was about 1 % relative by mass. However; under different conditions of humidity, he mass loss could vary. In order for users to directly relate heir ana^es to he certified value, loss on drying corrections should be measured and appEed at he time of the analysis.

Environmental Lend. Proficiency Analytical Testing Program Results: This material was included as an unknown in he Environmental Lead Proficiency Analytical Testing Program (ELPAT) administered by the American Industrial Hygiene Association (AIHA). Conventional dissolution methods employed by participating laboratories include ho^late, microwave, and oher techniques such as sealed bomb dissolutions and leaching techniques. Instrumental determinations were performed using inductively coupled plasma mass spectrometry (ICPMS), inductively coxpled plasma-optical emission spectrometry (ICP-OES), flame atomic absorption spectrometry (FAAS), graphite furnace atomic absorption spectrometry (OFAAS) and X-ray fluorescence spectrometry (XRF). Information from this stuify is provided to indicate the state of the practice for lead in paint measurements using su(h methods. A summary of the round robin lead results obtained from ELPAT Reference Laboratories for SRM 2581 is presented in Table 2. The SRM 2581 is identified as round robin 015, paint #3 in the ELPAT report.

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