McDonald Lauren T, Rasmussen Pat E, Chénier Marc, Levesque Christine
Earth Sciences Department, University of Ottawa, 140 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada.
J Environ Monit. 2011 Feb;13(2):377-83. doi: 10.1039/c0em00440e. Epub 2010 Dec 6.
Wipe sampling is the USA regulatory protocol for determination of "dust lead loadings" in residential environments. Few studies have applied the wipe sampling method to metals other than lead (Pb) for the purpose of residential exposure assessments. This study was undertaken to develop and expand the wipe method for quantifying additional metal(loid)s including arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and antimony (Sb); and to provide information on typical background loadings for these metals in urban Canadian homes. A total of 932 wipe samples, 220 field blanks, and 220 duplicate wipes were collected from 222 homes located in three cities in Ontario, Canada using the ASTM 1728 standard. The wipes were digested using a modified version of the ASTM 1644 standard for Pb, which prescribes a hot nitric acid/hydrogen peroxide digestion. The key modification was the addition of hydrofluoric acid to improve recoveries of the target elements, and determination using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Generally, a large proportion of the results fell below the limits of detection (LOD) and quantification (LOQ). To distinguish "elevated" metal loadings from loadings characterized as "urban background", an upper background threshold for each element was derived using a normality (Q-Q) plot. LOQ was determined to be the appropriate minimum threshold based on quality assurance criteria. It is concluded that wipes are a useful sampling option to investigate multi-element loadings in residential environments.
擦拭采样是美国用于测定居住环境中“粉尘铅含量”的监管协议。很少有研究将擦拭采样方法用于除铅（Pb）以外的金属，以进行居住环境暴露评估。本研究旨在开发并扩展擦拭方法，用于量化包括砷（As）、镉（Cd）、铬（Cr）、铜（Cu）、镍（Ni）和锑（Sb）在内的其他金属（类金属）；并提供加拿大城市家庭中这些金属典型背景含量的信息。使用ASTM 1728标准，从加拿大安大略省三个城市的222户家庭中总共采集了932个擦拭样本、220个现场空白样本和220个重复擦拭样本。擦拭样本采用针对铅的ASTM 1644标准的修改版本进行消解，该标准规定采用热硝酸/过氧化氢消解。关键的修改是添加氢氟酸以提高目标元素的回收率，并使用电感耦合等离子体质谱法（ICP-MS）进行测定。一般来说，大部分结果低于检测限（LOD）和定量限（LOQ）。为了区分“升高的”金属含量与被视为“城市背景”的含量，使用正态性（Q-Q）图得出每种元素的背景上限阈值。根据质量保证标准，确定LOQ为合适的最低阈值。得出的结论是，擦拭采样是调查居住环境中多元素含量的一种有用的采样方法。
