Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan; Seisen University, Research Institute for Cultural Studies, 3-16-21 Higashi Gotanda, Shinagawa-ku, Tokyo 141-8642, Japan.
Forensic Sci Int. 2018 Oct;291:230-233. doi: 10.1016/j.forsciint.2018.08.019. Epub 2018 Sep 5.
In cases of criminal thallium poisoning, forensic investigation is required to identify the amount and time of thallium exposure. Usually, blood and urine thallium levels are respectively used as biomarkers. Additionally, hair has the unique potential to reveal retrospective information. Although several studies have attempted to clarify how thallium is distributed in hair after thallium poisoning, none have evaluated the time course of changing thallium distribution. We investigated changes in the distribution of thallium in hair at different time points after exposure in five criminal thallotoxicosis patients. Scalp hair samples were collected twice, at 2.6 and 4.2-4.5months after an exposure incident by police. Results of our segmented analysis, a considerable amount of thallium was detected in almost all hair sample segments. The thallium exposure date estimated from both hair sample collections matched the actual exposure date. We found that determination of thallium amounts in hair samples divided into consecutive segments provides valuable information about exposure period even if a considerable time passes after exposure. Moreover, when estimating the amount of thallium exposure from a scalp hair sample, it is necessary to pay sufficient attention to individual differences in its decrease from hair.
在刑事铊中毒的情况下，需要进行法医调查以确定铊暴露的量和时间。通常，血液和尿液中的铊水平分别用作生物标志物。此外，头发具有揭示回溯信息的独特潜力。尽管已经有几项研究试图阐明铊中毒后头发中的铊分布情况，但没有一项研究评估过铊分布变化的时间过程。我们调查了五名刑事铊中毒患者在暴露后不同时间点头发中铊分布的变化。头皮头发样本分别在警察介入后的 2.6 个月和 4.2-4.5 个月时采集了两次。我们的分段分析结果显示，在几乎所有的头发样本段中都检测到了相当数量的铊。从两次头发样本采集中估计的铊暴露日期与实际暴露日期相符。我们发现，即使在暴露后相当长的时间内，将头发样本分成连续的段来确定其中的铊含量，也能提供有关暴露期的有价值信息。此外，在从头皮头发样本中估计铊暴露量时，需要充分注意个体之间头发中铊含量下降的差异。
