Horii Yuichi, van Bavel Bert, Kannan Kurunthachalam, Petrick Gert, Nachtigall Kerstin, Yamashita Nobuyoshi
Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA.
Chemosphere. 2008 Jan;70(7):1280-9. doi: 10.1016/j.chemosphere.2007.07.066. Epub 2007 Sep 7.
Elevated concentrations of dioxins in ancient ball clay from the Mississippi Embayment suggest natural formation of dioxins in the environment. Evidence for such natural formation in ball clay derives from unique congener profiles in undisturbed ancient clay deposits and from the lack of other anthropogenic contaminants. Here we present novel evidence of natural formation of dioxins based on congener-specific carbon isotopic analysis of octachlorodibenzo-p-dioxin (OCDD) in ball clays from the USA and Japan. The analyses were performed using a combination of double-column high performance liquid chromatography clean-up and two-dimensional gas chromatography-isotope ratio mass spectrometry. Elevated concentrations of OCDD found in ball clays from the USA and Japan were isotopically distinguished from the anthropogenic source materials (fly ash and pentachlorophenol) and environmental samples (sediment and soil). The isotopic signatures and the occurrence of OCDD in ancient ball clays deposited in the Tertiary Era provide evidence for the in situ formation of dioxins.
密西西比河沿岸古球粘土中二恶英浓度升高表明环境中二恶英可自然形成。球粘土中这种自然形成的证据源于未受干扰的古代粘土沉积物中独特的同系物分布以及缺乏其他人为污染物。在此，我们基于对来自美国和日本的球粘土中八氯二苯并 - 对 - 二恶英（OCDD）进行同系物特异性碳同位素分析，展示了二恶英自然形成的新证据。分析采用了双柱高效液相色谱净化与二维气相色谱 - 同位素比值质谱联用的方法。在美国和日本的球粘土中发现的OCDD浓度升高，在同位素上与人为源材料（飞灰和五氯苯酚）以及环境样品（沉积物和土壤）不同。第三纪沉积的古代球粘土中的同位素特征和OCDD的存在为二恶英的原位形成提供了证据。
