We compared inductively coupled plasma-mass spectrometry (ICP-MS) test results for the analysis of heavy metals (As, Ba, Cd, Hg, Pb, and Se) in pet foods and routine veterinary diagnostic specimens using intralaboratory and interlaboratory comparisons. Four laboratories, 1 principal laboratory and 3 collaborating laboratories, conducted instrument comparison (limit of detection [LOD], limit of quantification [LOQ], and linear dynamic range [LDR] on 24 data sets), in-house method comparison (accuracy and precision on 120 data sets), and interlaboratory comparison (reproducibility on 528 data sets using Horwitz equation analysis). Matrices tested included 2 types of pet food jerky treats (chicken and sweet potato), bovine blood, and bovine liver and kidney. The instrument comparison study confirmed that ICP-MS provided the sensitivity necessary for the analysis of all heavy metals tested at concentrations below the level of concern for routine diagnostic testing. The "in-house" method comparison samples, spiked at low (0.04 µg/g), medium (0.4 µg/g), and high (8.0 µg/g; note: the high validation level spike for mercury was 2 µg/g) concentration levels, indicated that ICP-MS can meet U.S. FDA acceptance criteria for both accuracy (90-105% recovery) and precision (< 6% coefficient of variation). The interlaboratory comparison studies showed that ICP-MS is a reproducible method for the analysis of heavy metals (HorRat value of 0.5-2.0) except for mercury in one laboratory, which used a different sample preparation method (open block rather than microwave digestion). Overall, our study showed that ICP-MS is a reproducible method for the analysis of heavy metals in spite of minor differences in methodology.

中文翻译：

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使用电感耦合等离子体质谱法对动物诊断样本和饲料中的重金属进行实验室间比较。

我们使用实验室内和实验室间比较，比较了电感耦合等离子体质谱（ICP-MS）测试结果对宠物食品和常规兽医诊断标本中重金属（As，Ba，Cd，Hg，Pb和Se）的分析。四个实验室（1个主要实验室和3个合作实验室）进行了仪器比较（24个数据集的检出限[LOD]，定量限[LOQ]和线性动态范围[LDR]），内部方法比较（准确性和准确性） 120个数据集的精确度）和实验室间比较（使用Horwitz方程分析的528个数据集的可重复性）。测试的矩阵包括2种类型的宠物食品生涩零食（鸡肉和番薯），牛血以及牛肝肾。仪器比较研究证实，ICP-MS提供了分析浓度低于常规诊断测试所关注浓度的所有重金属所需的灵敏度。“内部”方法比较样品，分别以低（0.04 µg / g），中（0.4 µg / g）和高（8.0 µg / g）加标；注意：汞的高验证水平加标为2 µg / g ）浓度水平，表明ICP-MS可以满足美国FDA的准确度（90-105％回收率）和精确度（<6％变异系数）的接受标准。实验室间的比较研究表明，ICP-MS是一种可重现的分析重金属（HorRat值为0.5-2.0）的方法，但在一个实验室中，汞使用的是另一种样品制备方法（开放块而不是微波消解）。总体，