意外的石油泄漏到海洋中会导致石油作为海洋雪的一部分向下运输和沉降到海底,正如在2010年墨西哥湾深水地平线事件中看到的那样。北极和亚北极地区可能有利于导致底栖石油沉积的条件,引发了对底栖群落潜在影响的质疑。这项研究调查了受石油污染的海洋积雪对蓝色贻贝的影响(Mytilussp。).我们将贻贝暴露于1)受石油污染的海洋雪(MOS处理)四天,或2)油和未聚集的食物颗粒的化学增强的水容纳部分(CEWAF)(CEWAF处理)。两种油处理接受相同标称浓度的油和食物。包括两个对照:1)清洁海水加上未聚集的食物(无agg控制)和2)清洁海水加上海洋雪(海洋雪控制)。曝光后,贻贝被允许在清洁下恢复十天,运行的海水。样本是在暴露期之前和之后采集的,并且在以下终点的回收阶段之后:海水和MOS之间的油化合物的分布(分配),在海水和贻贝组织之间;DNA损伤(通过彗星测定法评估);清除率;和条件指数[组织干重(g)除以壳长(mm)]。在海水和MOS之间的油化合物分配中发现了一些可辨别的模式。然而,这些模式并没有转化为两种油处理之间的油化合物分配到贻贝组织中的任何显着差异。DNA损伤不超过背景水平(10%或更低的尾部DNA;在健康人群中,活细胞)在任何采样时间点,但是在恢复期后,与MOS-T贻贝相比,CEWAF-T中的DNA损伤明显更高。曝光后,CEWAF治疗和无agg对照之间的清除率出现显着差异,但不是在MOS处理和海洋降雪控制之间。暴露时间后,除CEWAF处理外,所有贻贝的状况指数均增加。一起,这些结果表明,聚集体可以缓和油暴露对蓝贻贝的影响,可能通过提供更好的,营养比未聚集的食物颗粒更浓缩。
Accidental oil spills into the ocean can lead to downward transport and settling of oil onto the seafloor as part of marine snow, as seen during the Deepwater Horizon incident in 2010 in the Gulf of Mexico. The arctic and subarctic regions may favor conditions leading to this benthic oil deposition, prompting questions about the potential impacts on benthic communities. This study investigated the effects of oil-contaminated marine snow uptake on the blue mussel (Mytilus sp.). We exposed mussels for four days to 1) oil-contaminated marine snow (
MOS treatment), or to 2) chemically-enhanced water-accommodated fraction (CEWAF) of oil plus unaggregated food particles (CEWAF treatment). Both oil treatments received the same nominal concentration of oil and food. Two controls were included: 1) Clean seawater plus unaggregated food (agg-free control) and 2) clean seawater plus marine snow (marine snow control). After the exposure, mussels were allowed to recover for ten days under clean, running seawater. Samples were taken right before and after the exposure period, and after the recovery phase for the following endpoints: distribution (partitioning) of oil compounds between seawater and
MOS, and between seawater and mussel tissue; DNA damage (assessed via the comet assay); clearance rate; and condition index [tissue dry weight (g) divided by shell length (mm)]. Some discernable patterns were found in the partitioning of oil compounds between seawater and
MOS. However, these patterns did not translate to any significant differences in the partitioning of oil compounds into mussel tissue between the two oil treatments. DNA damage did not exceed background levels (10% tail DNA or less; to be expected in healthy, viable cells) at any sampling time point, but significantly higher DNA damage was observed in CEWAF-T compared to
MOS-T mussels after the recovery phase. After the exposure, a significant difference emerged in the clearance rate between the CEWAF treatment and the agg-free control, but not between the
MOS treatment and the marine snow control. All mussels except those from the CEWAF treatment exhibited an increased condition index after the exposure time. Together, these results suggest that aggregates could moderate the effects of oil exposure on blue mussels, possibly by providing better, more concentrated nutrition than unaggregated food particles.