Coastal sediments subjected to high anthropogenic impacts can accumulate large amounts of polycyclic aromatic hydrocarbons (PAHs) and metals, demanding effective and eco-sustainable remediation solutions. In this study, we carried out bioremediation experiments on marine sediments highly contaminated with PAHs and metals. In particular, we investigated the effects of biostimulation (by the addition of inorganic nutrients), bioaugmentation (by the addition of fungi belonging to Aspergillus sp.) and microbial fuel cell-based strategies on PAH degradation and on changes in metal partitioning. Results reported here indicate that all biotreatments determined a significant decrease of PAH concentrations (at least 60%) in a relatively short time interval (few weeks) and that biostimulation was the most effective approach (>90%). Biostimulation determined a faster degradation rate of high than low molecular weight PAHs, indicating a preferential biodegradation of specific PAH congeners. At the same time, the biotreatments changed the partitioning of metals, including their solubilization, suggesting the need of parallel environmental risk assessment. Our findings also suggest that ex situ biotreatments can have a lower carbon footprint than current management options of contaminated sediments (i.e., landfill disposal and/or disposal in confined aquatic facilities), but integration with other strategies for metal removal (e.g. through bioleaching) from sediments is needed for their safe re-use. Overall, results presented here provide new insights into the development of effective and eco-sustainable bioremediation strategies for the reclamation of highly contaminated marine sediments.

受到高人为影响的沿海沉积物会积聚大量多环芳烃（PAH）和金属，因此需要有效且生态可持续的补救方案。在这项研究中，我们对被PAHs和金属高度污染的海洋沉积物进行了生物修复实验。特别是，我们研究了生物刺激（通过添加无机营养物），生物增强（通过添加属于曲霉属真菌）的作用。sp。）以及基于微生物燃料电池的PAH降解和金属分配变化的策略。此处报道的结果表明，所有生物处理均在相对较短的时间间隔（几周）内确定了PAH浓度的显着降低（至少60％），并且生物刺激是最有效的方法（> 90％）。生物刺激作用确定了高降解率比低分子量PAH更快，表明特定PAH同系物优先发生了生物降解。同时，生物处理改变了金属的分配，包括它们的溶解，表明需要并行的环境风险评估。我们的研究结果还表明，易地生物处理的碳足迹可能比目前受污染沉积物的管理方案（即，垃圾填埋处理和/或在受限水生设施中的处置）要低，但是为了安全回收，需要与其他从沉积物中去除金属（例如通过生物浸出）的策略整合-使用。总体而言，此处介绍的结果为开发用于高度污染的海洋沉积物的有效和生态可持续的生物修复策略的开发提供了新见解。