Microplastic (MP) pollution in marine environments and organisms has received substantial international attention. However, long-term field studies of MPs are scarce. Here, we assessed the seasonal variation in MP abundance in the Zhoushan fishing ground (ZFG), one of the most abundant and productive fishing grounds worldwide, and analyzed the long-term MP accumulation in fish gastrointestinal tracts from September 2017 to June 2018. The most common MP particles in the ZFG were polyethylene terephthalate and polypropylene. After four seasons of continuous monitoring, we did not find accumulation of MPs in the fish after 10% KOH digestion. In total, 254 MP particles were removed from the gastrointestinal tracts of all fish. The average number of particles per fish was lower than that reported in previous global marine studies. There were significant differences among species. Moreover, this study provides the calculation of the weight of MPs ingested by fish and an estimate of the load of accumulated MPs in fish. According to the estimation, the load of MPs ingested by fish annually was approximately 3 kg in ZFG. These findings provide the long-term evidence of MP contamination in biota from the ZFG. The amounts of MPs ingested by fish require more detailed and improved investigation and estimation in further studies.

海洋环境和生物体中的微塑料 (MP) 污染已受到国际上的广泛关注。然而，对议员的长期实地研究很少。在这里，我们评估了舟山渔场 (ZFG) 中 MP 丰度的季节性变化，舟山渔场是世界上最丰富和最多产的渔场之一，并分析了 2017 年 9 月至 2018 年 6 月鱼类胃肠道中 MP 的长期积累。 ZFG 中最常见的 MP 颗粒是聚对苯二甲酸乙二醇酯和聚丙烯。经过四个季节的连续监测，我们在10% KOH消化后没有发现鱼体内MPs的积累。总共从所有鱼的胃肠道中去除了 254 个 MP 颗粒。每条鱼的平均颗粒数低于先前全球海洋研究报告的数量。种间存在显着差异。此外，这项研究提供了鱼类摄入 MPs 重量的计算和鱼类累积 MPs 负荷的估计。据估计，ZFG 每年鱼类摄入 MPs 的负荷约为 3 kg。这些发现提供了 ZFG 生物群中 MP 污染的长期证据。鱼类摄入的 MPs 的数量需要在进一步的研究中进行更详细和改进的调查和估计。