Bioremediation of sediments contaminated with polycyclic aromatic hydrocarbons: the technological innovation patented review

Sediment contamination with polycyclic aromatic hydrocarbons represents a major environmental concern worldwide. The different remediation strategies proposed are mainly based on physico-chemical and biological approaches. Physico-chemical methods (also referred to as conventional methods), although more efficient in several cases, are considered as less sustainable as a result of their higher environmental and economic costs. Biotechnological methods on the other hand, which make use of microorganisms and/or their metabolic products, have received increased attention as a more environment friendly and less costly alternative, although usually more time consuming. The various biotechnological approaches developed and patented on bioremediation of sediments polluted with polycyclic aromatic hydrocarbons are presented in this review, as well as some soil bioremediation methods considered applicable to sediments. Patents on sediment microbial fuel cells and other electrokinetic approaches are also included as considerable advances have been made in this field. Over 150 patents dating from 1995 to 2019 were collected from Espacenet platform, a worldwide patent database and considered in the present review. Overall, this review highlighting strengths and weaknesses of the various biotechnological approaches developed and patented, so far, can be useful to address further studies to improve bioremediation performance and can represent a benchmark of information for bioremediation companies to identify and explore the most promising field applicable approaches.