墨西哥奥阿哈卡州饮用水中的氧同位素变化及其对法医来源研究工作的影响
1California State University, Chico, 400 W. 1st St., Chico CA 95926, USA.
Science & justice : journal of the Forensic Science Society
|November 29, 2023
概括
在法医人类学中,氧同位素分析 (δ18O) 可能会错误地识别起源. 墨西哥Oaxaca的自来水不反映当地饮用水,这影响了来源估计方法的准确性.
科学领域:
- 法医人类学 法医人类学
- 地质化学 地质化学
- 同位素分析的分析.
背景情况:
- 氧同位素分析 (δ18O) 在法医人类学中用于根据组织组成估计个体的原产地.
- 这种方法通常假定自来水以同位素形式代表了当地的饮用水源.
- 以前的研究表明,饮用水同位素中的地理模式.
研究的目的:
- 批判性地评估该假设,自来水是同位素代表的饮用水在奥阿克萨卡,墨西哥.
- 评估现有模型的预测能力,将头发素与该地区的饮用水同位素联系起来.
- 在法医人类学中识别氧同位素分析的潜在局限性,特别是在非西方背景下.
主要方法:
- 来自墨西哥瓦哈卡的饮用水样本的氧气同位素成分 (δ18O) 分析.
- 俄阿克萨斯州饮用水的 δ18O 值与墨西哥自来水同层图的预测值进行比较.
- 对大哈萨克州的头发样本进行 δ18O 的分析,与各种水源进行比较.
主要成果:
- 发现奥阿哈卡的自来水 δ18O 值并不能可靠地反映当地的饮用水的同位素组成.
- 基于自来水假设的模型,将头发角蛋白与饮用水相关联,在本研究中缺乏预测能力.
- 显著的差异凸显了在同位素分析中使用自来水作为饮用水的替代品的潜在不正确性.
结论:
- 龙头水以同位素形式代表饮用水的假设在墨西哥奥阿哈卡是不可靠的.
- 目前依靠这一假设的法医人类学方法可能会导致错误的原产地估计,特别是在非西方社区.
- 需要进行进一步的研究,以了解影响 δ18O 值的其他因素,并适应各种社会文化背景的方法.
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