Chlorine-36 as a Tracer of Perchlorate Origin
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- 作者：Neil C. Sturchio ; Marc Caffee ; Abelardo D. Beloso ; Jr. ; Linnea J. Heraty ; John Karl Bhlke ; Paul B. Hatzinger ; W. Andrew Jackson ; Baohua Gu ; Jeffrey M. Heikoop ; Michael Dale
- 刊名：Environmental Science & Technology
- 出版年：2009
- 出版时间：September 15, 2009
- 年：2009
- 卷：43
- 期：18
- 页码：6934-6938
- 全文大小：135K
- 年卷期：v.43,no.18(September 15, 2009)
- ISSN：1520-5851
文摘
Perchlorate (ClO4−) is ubiquitous in the environment. It is produced naturally by atmospheric photochemical reactions, and also is synthesized in large quantities for military, aerospace, and industrial applications. Nitrate-enriched salt deposits of the Atacama Desert (Chile) contain high concentrations of natural ClO4−, and have been exported worldwide since the mid-1800s for use in agriculture. The widespread introduction of synthetic and agricultural ClO4− into the environment has contaminated numerous municipal water supplies. Stable isotope ratio measurements of Cl and O have been applied for discrimination of different ClO4− sources in the environment. This study explores the potential of 36Cl measurements for further improving the discrimination of ClO4− sources. Groundwater and desert soil samples from the southwestern United States (U.S.) contain ClO4− having high 36Cl abundances (36Cl/Cl = 3100 × 10−15 to 28,800 × 10−15), compared with those from the Atacama Desert (36Cl/Cl = 0.9 × 10−15 to 590 × 10−15) and synthetic ClO4− reagents and products (36Cl/Cl = 0.0 × 10−15 to 40 × 10−15). In conjunction with stable Cl and O isotope ratios, 36Cl data provide a clear distinction among three principal ClO4− source types in the environment of the southwestern U.S.