Previous research has shown that unspiked OECD 309 tests can be used to quantify chemical biodegradation in surface waters, relying on chemical residues already present in the water. Here we test the hypothesis that unspiked OECD 309 tests can quantitatively predict chemical persistence in the environment by comparing chemical half-lives assessed in the laboratory against those measured in the field. The study object was a Swedish lake heavily impacted by treated municipal wastewater. Half-lives in the field were measured by mass balance over 12 weeks. In parallel, half-lives in the lab were determined with an unspiked OECD 309 test run for 60 days. Chemical analysis was conducted using a non-target screening approach. The field study yielded a half-life <100 days for 38 chemicals for which the dominant source was wastewater; 32 of these were also detected in the lab test, whereby 18 had half-lives with a well-constrained uncertainty that did not intersect infinity. For 14 of the 18 chemicals, the field and lab half-lives agreed within a factor 3. In summary, the lab test predicted chemical attenuation in the field well. Limitations of the approach include the need for measurable chemical concentrations in the water body and failure to account for some attenuation mechanisms like phototransformation.

中文翻译：

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比较使用未加标OECD 309测试评估的非目标化学持久性与现场测量结果。

先前的研究表明，未加标样的OECD 309测试可以依靠水中已经存在的化学残留物来量化地表水中的化学生物降解。在这里，我们通过比较实验室中评估的化学半衰期与现场测得的化学半衰期，来检验未加标的OECD 309测试可以定量预测环境中化学持久性的假设。研究对象是瑞典湖泊，受到处理过的城市废水的严重影响。田间半衰期通过12周内的质量平衡来衡量。同时，通过未加标样的OECD 309测试运行60天来确定实验室的半衰期。使用非目标筛选方法进行化学分析。现场研究得出了38种化学品的半衰期<100天，其中主要来源是废水。在实验室测试中也检测到其中的32个，其中18个半衰期具有很好的约束不确定性，没有与无限相交。对于18种化学药品中的14种，现场和实验室的半衰期在3因子之内达成一致。总而言之，实验室测试预测了现场井中化学物质的衰减。该方法的局限性包括在水体中需要可测量的化学浓度，并且无法考虑到某些衰减机制，例如光转化。