Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University , 10691 Stockholm, Sweden.
Environ Sci Technol. 2015 Feb 3;49(3):1646-53. doi: 10.1021/es505548k. Epub 2015 Jan 22.
It is challenging to measure the persistence of chemicals under field conditions. In this work, two approaches for measuring persistence in the field were compared: the chemical mass balance approach, and a novel chemical benchmarking approach. Ten pharmaceuticals, an X-ray contrast agent, and an artificial sweetener were studied in a Swedish lake. Acesulfame K was selected as a benchmark to quantify persistence using the chemical benchmarking approach. The 95% confidence intervals of the half-life for transformation in the lake system ranged from 780-5700 days for carbamazepine to <1-2 days for ketoprofen. The persistence estimates obtained using the benchmarking approach agreed well with those from the mass balance approach (1-21% difference), indicating that chemical benchmarking can be a valid and useful method to measure the persistence of chemicals under field conditions. Compared to the mass balance approach, the benchmarking approach partially or completely eliminates the need to quantify mass flow of chemicals, so it is particularly advantageous when the quantification of mass flow of chemicals is difficult. Furthermore, the benchmarking approach allows for ready comparison and ranking of the persistence of different chemicals.
在野外条件下测量化学品的持久性具有挑战性。在这项工作中，比较了两种在野外测量持久性的方法：化学质量平衡法和一种新的化学基准法。十种药物、一种 X 射线造影剂和一种人工甜味剂在瑞典湖中进行了研究。选定乙酰磺胺酸钾作为基准物质，使用化学基准法来量化持久性。在湖泊系统中，十种药物和一种人工甜味剂的转化半衰期的 95%置信区间范围从卡马西平的 780-5700 天到酮洛芬的<1-2 天。使用基准法获得的持久性估计与质量平衡法（1-21%的差异）一致，这表明化学基准法可以是一种有效和有用的方法，用于测量野外条件下化学品的持久性。与质量平衡法相比，基准法部分或完全消除了量化化学品质量流量的需求，因此在量化化学品质量流量困难时特别有利。此外，基准法允许对不同化学品的持久性进行现成的比较和排序。
