Cole J, Beare D M, Waugh A P, Capulas E, Aldridge K E, Arlett C F, Green M H, Crum J E, Cox D, Garner R C, Dingley K H, Martin E A, Podmore K, Heydon R, Farmer P B
MRC Cell Mutation Unit, University of Sussex, Falmer, Brighton, United Kingdom.
Environ Mol Mutagen. 1997;30(2):97-111.
In January 1993 the oil tanker Braer ran aground in the Shetland Islands, Scotland. Approximately 80,000 tons of crude oil were released. Exceptionally high winds caused extensive pollution and exposure of the local population to crude oil. We describe the study which was immediately set in place to examine the exposed population for evidence of genotoxic exposure. Blood samples were taken and primary DNA damage was measured in the mononuclear cell fraction by the butanol modification of the 32P-postlabelling method. Mutation was measured at the hprt locus in T lymphocytes. No evidence of genotoxicity was obtained for either end point, but nevertheless, we believe that useful lessons were learnt, which should be incorporated into the design of future studies: (1) A rapid response is essential, and even if sufficient funds are not immediately available, it is still worth attempting to obtain samples quickly and use cryopreservation, also to attempt to estimate exposure. (2) Adequate numbers of volunteers must be sought, together with enough controls, not just to allow meaningful analysis but to overcome loss of samples and failure of things to go according to plan. (3) Points concerning laboratory practice include: (i) samples should be coded, (ii) clearly defined and proven protocols should be used, (iii) irreplaceable samples should not be used for method development, (iv) should a problem become apparent during the study, work on such samples should cease immediately until the problem is solved, (v) all critical experimental components should be pretested against a laboratory standard. (4) The study design should include replicate experiments to monitor experimental variability and reproducibility, as well as internal standards and cryopreserved "in house" samples. Care must be taken that samples from any one exposure group are spread between a number of independent experiments and that each experiment includes samples from a number of exposure groups. (5) A computerised data base should be maintained with full details of experimental variables, donor attributes, and raw data so that any contribution of experimental artefacts to "outlier" results can be monitored. (6) Because of the nature of the statistical variation for many environmental genotoxicity end points, only a large-scale study is likely to be capable of yielding useful information.
1993年1月，油轮“布雷尔号”在苏格兰设得兰群岛搁浅。约8万吨原油泄漏。狂风导致了大面积污染，当地居民也接触到了原油。我们描述了立即开展的一项研究，该研究旨在检查受影响人群是否有基因毒性暴露的证据。采集了血样，并通过32P后标记法的丁醇修饰法测定单核细胞部分的原发性DNA损伤。在T淋巴细胞的hprt位点测量突变。两个终点均未获得基因毒性证据，但尽管如此，我们认为还是吸取了一些有益的经验教训，应将其纳入未来研究的设计中：（1）快速反应至关重要，即使没有立即获得足够资金，仍值得尽快尝试获取样本并进行冷冻保存，同时也要尝试估计暴露情况。（2）必须寻求足够数量的志愿者以及足够的对照，这不仅是为了进行有意义的分析，也是为了克服样本丢失和事情未按计划进行的情况。（3）有关实验室操作的要点包括：（i）样本应进行编码，（ii）应使用明确界定且经过验证的方案，（iii）不可替代的样本不应用于方法开发，（iv）如果在研究过程中出现问题，应立即停止对这些样本的研究，直到问题解决，（v）所有关键实验组件都应根据实验室标准进行预测试。（4）研究设计应包括重复实验，以监测实验变异性和可重复性，以及内部标准和冷冻保存的“内部”样本。必须注意的是，任何一个暴露组的样本应分散在多个独立实验中，并且每个实验应包括多个暴露组的样本。（5）应维护一个计算机化数据库，详细记录实验变量、供体属性和原始数据，以便能够监测实验假象对“异常值”结果的任何影响。（6）由于许多环境基因毒性终点的统计变异性质，只有大规模研究才可能产生有用信息。
