The human hair is a potential material for assessing the exposure to environmental contaminants and tracing human mobility. Although various digestion methods have been proposed for determining trace elements in the human hair, there is no consensus about the best method among them yet. We examined five different methods in order to determine the best method yielding the most accurate and precise data of trace elements in the human hair using two certified reference human hairs (IAEA085 and IAEA086) under controlled conditions (temperature, the volume of hydrogen peroxide (H2O2), and the number of digestion). Results showed that a high temperature of 160 °C yields better recovery rates than a low temperature of 70 °C. Furthermore, the additional input of H2O2 increases the recovery rate from 90 to 102%, and the two-time digestion also promotes the recovery rate. This study suggests that although the combination of high temperature (160 °C), high volume of H2O2 (0.4 mL), and two-time digestion yields the most accurate and precise data of trace elements in the human hair, the digestion method should be carefully selected depending on the content of organometallic cation.

中文翻译：

---

重新审视人发中微量元素分析的消解方法

人的头发是评估暴露于环境污染物和追踪人类活动的潜在材料。虽然已经提出了各种消化方法来测定人发中的微量元素，但目前还没有对其中最好的方法达成共识。我们检查了五种不同的方法，以确定在受控条件下（温度、过氧化氢 (H2O2 )，以及消化次数)。结果表明，160 °C 的高温比 70 °C 的低温产生更好的回收率。此外，额外输入 H2O2 将回收率从 90% 提高到 102%，二次消化也促进了回收率。本研究表明，虽然高温 (160 °C)、高体积 H2O2 (0.4 mL) 和两次消解相结合可以得到最准确、最精确的人发中微量元素数据，但消解方法应根据有机金属阳离子的含量精心选择。