COMPARISON BETWEEN SOXHLET AND MICROWAVE EXTRACTION TECHNIQUES FOR POLYCYLIC AROMATIC HYDROCARBONS IN LIVER AND ADIPOSE TISSUES OF MARINE TETRAPODS AND EVALUATION OF THE HETEROGENEITY OF TISSUES

For the evaluation of PAH extraction techniques in adipose and liver tissues of marine tetrapod, samples of some species (Pontoporia blainvillei, Chelonia mydas, Thalassarche melanophris, and Balaenoptera brydei) were spiked with PAH standards and extracted using soxhlet system and microwave oven. The results of both extraction techniques for the two different tissues of the four species of tetrapod were within the quality assurance and quality control criteria, that means both extraction techniques produced acceptable recoveries for surrogate and spiked compounds added to the sample tissues. Although both techniques of extraction met quality criteria and were considered suitable for extraction of marine tetrapod tissues, the soxhlet system produced a higher recovery of the spiked compounds and a lower standard deviation between the replicates than the microwave extraction; therefore the soxhlet system was considered the more efficient extraction method for PAH. The evaluation of liver and adipose tissue PAH accumulation, as well as the influence of tissue heterogeneity, was impaired as the concentrations of PAHs in almost all samples were lower than the detection limits of the analytical method.为评估海洋四足动物脂肪组织与肝脏组织中的多环芳烃（PAH）萃取技术，本研究选取拉普拉塔河豚（Pontoporia blainvillei）、绿海龟（Chelonia mydas）、黑眉信天翁（Thalassarche melanophris）以及布氏鲸（Balaenoptera brydei）四个物种的样品，向样品中添加多环芳烃标准品完成加标处理，分别采用索氏提取系统（Soxhlet system）与微波萃取装置（microwave oven）进行萃取。针对该四种海洋四足动物的两种不同组织，两种萃取技术的检测结果均符合质量保证与质量控制准则，即两种方法对添加至样品组织中的替代化合物与加标化合物均可获得可接受的回收率。尽管两种萃取技术均满足质量准则且适用于海洋四足动物组织的萃取，但相较于微波萃取法，索氏提取系统对加标化合物的回收率更高，平行样间的标准偏差更低；因此索氏提取法被认为是更高效的多环芳烃萃取方法。由于几乎所有样品中的多环芳烃浓度均低于分析方法的检出限，针对肝脏与脂肪组织中多环芳烃积累量以及组织异质性影响的评估工作受到了阻碍。