Abstract

As an expert body, the Oil Spill Identification Network of experts within the Bonn Agreement (OSINet) developed a common methodology for oil identification (denoted CEN/Tr 15522-2 for 1st and 2nd, and EN15522-2 for the upcoming 3rd edition) published by the European Committee for Standardization (CEN). OSINet decided that the 3rd edition of the methodology should expand on diagnostic ratios for light to mid-range petroleum distillates (LMPD). Many ratios involving light petroleum biomarkers have been proposed by the oil spill community, based on literature, in-house studies and case work experience. To establish a normative set of approximately 25 ratios for light biomarkers, OSINet decided to apply six criteria. Three criteria concern easily obtained information, on similarities in (1) retention time, and (2) mass-to-charge ratio, and (3) sufficient variation in compound classes. The present study was initiated to increase knowledge on the three remaining criteria: (4) documented weathering susceptibility of biomarkers, which was done by a biodegradation experiment of diesel in soil and supported by additional literature studies, (5) ubiquitous presence of proposed compounds in LMPD, and (6) good discriminative ability between sources. The last two criteria were studied using 87 unique non-weathered oil samples from 14 countries and supplementary literature data. The experimental results and the literature studies for criterion 4 demonstrated that LMPD will be susceptible to pronounced evaporation in an open environment, resulting in extensive information loss over time. Relative to evaporation, the processes of dissolution and photo-oxidation will generally play a limited part in weathering for these products. Signs of biodegradation will have reduced incidence of fatty acid methyl esters (FAMEs), n-alkanes and compounds including long straight-chain alkyl substituents. Of 78 ratios initially evaluated for criteria 5 and 6, many compounds were not detected at sufficient levels in LMPD or did not meet the requirements on analytical performance. After this collaborative study, 39 proposed ratios remained as candidates for a normative set. Based on information on all six criteria, OSINet aims at making an informed decision about diagnostic ratios for light petroleum biomarkers in the 3rd edition of the CEN methodology.

摘要

作为一个专家机构，波恩协定内的溢油识别专家网络（OSINet）开发了一种通用的识别油的方法（第1和第2版为CEN / Tr 15522-2，在即将发布的第3版中表示为EN15522-2）由欧洲标准化委员会（CEN）提供。OSINet决定，该方法的第三版应扩大轻中型石油馏出物（LMPD）的诊断率。溢油界根据文献，内部研究和案例工作经验提出了许多涉及轻质石油生物标志物的比率。为了为轻型生物标志物建立一套约25个比率的规范集，OSINet决定采用六个标准。关于（1）保留时间和（2）质荷比，（3）复合类别的足够变化。开展本研究是为了增加对其余三个标准的了解：（4）记录了生物标志物的风化敏感性，这是通过土壤中柴油的生物降解实验完成的，并得到了其他文献研究的支持；（5） LMPD，以及（6）来源之间的良好区分能力。使用来自14个国家的87个独特的非风化油样品和补充文献数据对后两个标准进行了研究。实验结果和针对标准4的文献研究表明，LMPD在开放环境中将易于明显蒸发，从而导致信息随时间流逝而大量丢失。相对于蒸发，这些产品的溶解和光氧化过程通常会在耐候性方面发挥有限的作用。生物降解的迹象将减少脂肪酸甲酯（FAME）的发生，正构烷烃和包括长直链烷基取代基的化合物。在最初针对标准5和6评估的78个比率中，在LMPD中未检测到足够水平的许多化合物，或者未满足分析性能要求。在这项合作研究之后，建议的39个比率仍可作为规范集的候选者。基于所有六个标准的信息，OSINet旨在在第三版CEN方法论中就轻质石油生物标志物的诊断率做出明智的决定。