Department of Veterinary Medicine, University of Alaska Fairbanks, 2141 Koyukuk Dr, Fairbanks, AK, 99775-7750, USA.
Centro de Investigaciones Biológicas Del Noroeste, S.C. Planeación Ambiental Y Conservación, Instituto Politécnico Nacional 195, Playa Palo de Santa Rita Sur, 23096, La Paz, Baja California Sur, Mexico.
Arch Environ Contam Toxicol. 2023 Aug;85(2):119-128. doi: 10.1007/s00244-023-01020-2. Epub 2023 Aug 12.
Rapid and effective quantification of total mercury concentrations ([THg]) in fish muscle is an important part of ongoing monitoring to provide reliable and near real-time public health guidance. Methods for quantifying THg in fish muscle frequently require the use of large sample mass and numerous preparation steps. Wet (aka fresh weight) biopsy punch samples of fish muscle have been used to quantify THg directly, without drying and homogenization. Both methods have advantages and disadvantages. We compare the use of fresh weight biopsy punches for quantifying THg to using larger, dried homogenized samples. The [THg] determination for the two sampling methods was EPA method 7473. Three separate biopsy punch samples and a large muscle sample were taken from each fish and analyzed on a Direct Mercury Analyzer. There were no statistical differences between mean log transformed wet weight [THg] from biopsy punches and homogenized muscle across all samples or within individual species. Similarly, across the range of [THg] (7.5-612.7 ng/g ww), linear regression of [THg] from biopsy punch and homogenized muscle samples was not different from a 1:1 linear relationship. Linear regression statistics of [THg] with fish fork length produced similar results for both biopsy punch and homogenized muscle samples. However, the coefficient of variation among biopsy punch replicates for individual fish was frequently above the acceptable threshold of 15%. We recommend biopsy punches be used as an effective tool for broad-scale rapid monitoring of fish resources for Hg, while homogenized muscle samples be used for fine-scale ecological and health questions.
快速有效地定量测定鱼肉中的总汞浓度 ([THg]) 是持续监测的重要组成部分，可为公众健康提供可靠的、近乎实时的指导。测定鱼肉中 THg 的方法通常需要使用大量样本和繁琐的准备步骤。湿（即新鲜重量）活检鱼肌肉穿刺样本可直接用于定量测定 THg，无需干燥和均化。这两种方法各有优缺点。我们比较了直接使用新鲜重量活检穿刺样本与使用较大的、干燥的匀浆样本来定量测定 THg。两种采样方法的 [THg] 测定均采用 EPA 方法 7473。从每条鱼中取出三个单独的活检穿刺样本和一个大的肌肉样本，并在直接测汞仪上进行分析。在所有样本或单个物种中，活检穿刺样本的湿重 [THg] 的对数平均值与匀浆肌肉样本之间没有统计学差异。同样，在 [THg] （7.5-612.7 ng/g ww）范围内，活检穿刺和匀浆肌肉样本的 [THg] 线性回归与 1:1 线性关系无差异。活检穿刺和匀浆肌肉样本的 [THg] 与鱼叉长的线性回归统计结果也相似。然而，个别鱼的活检穿刺重复样本之间的变异系数经常高于 15%的可接受阈值。我们建议使用活检穿刺作为快速监测鱼类资源中 Hg 的有效工具，同时使用匀浆肌肉样本来解决更精细的生态和健康问题。
