Pesticide residues are analyzed in thousands of samples yearly by national authorities and private laboratories. Intensive research is ongoing to develop new methods or improve existing ones concentrating on the extraction, cleanup, and detection techniques. Little attention has been paid to the contribution of prior steps in the determination process to the overall laboratory sampling error, though several publications demonstrated their practical importance. Consequently, the repeatability and reproducibility of the results are often reported based on the recovery tests alone. A few previous publications are cited in this paper which illustrate the magnitude of random error derived from subsampling, comminution of analytical sample and selection of small test portions.

中文翻译：

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农药残留分析结果随机变化的来源

国家主管部门和私人实验室每年对数千种样品中的农药残留进行分析。正在进行深入的研究，以开发新方法或改进现有方法，重点在于提取，净化和检测技术。尽管有几篇出版物证明了它们的实际重要性，但对测定过程中先前步骤对实验室总体采样误差的贡献却鲜有关注。因此，通常仅根据恢复测试报告结果的可重复性和可重复性。本文引用了一些以前的出版物，这些出版物说明了从二次采样，粉碎分析样品和选择小的测试部分中得出的随机误差的大小。