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1. Introduction
During the last few years, an increase in organic contaminants in water due to accelerated development and industrialization growth has been detected. Many of these contaminants are considered potentially toxic to the environment and to human health. For that reason, water sheds contaminated with organic contaminants have gained considerable worldwide concern [1,2].
One type of these organic contaminants is polycyclic aromatic hydrocarbons (PAHs), which have caught scientists’ attention due to their mutability, carcinogenicity, and toxicity. Such compounds originate from oil spills and from incomplete combustion. They are prone to biomagnification in addition to long-distance transport [3].
Other possible PAH sources are agriculture, agricultural runoff, and wastewater from industrial plants. These sources play an important role in water supply and irrigation; therefore, water quality is strongly related to health. Nevertheless, available information on public risk in relation to water quality is very limited [4]. Despite these compounds’ low water solubility, they can be found in concentrations at the µg L−1 (ppb) level. Such levels are considered toxic, hence the relevance of their quantification [5].
In addition, PAHs are difficult to eliminate from natural matrices [6]. Physicochemical treatments, such as steam distillation, solidification, chemical precipitation, and incineration, have been implemented in efforts to eliminate these contaminants. However, these methods tend to transport contaminant compounds from one place to another rather than eliminate them. In addition, these treatments can involve other economic costs due to the generation of toxic byproducts that require additional treatment [7]. On the other hand, bioremediation initiatives offer enduring solutions. Such methods are deferential to the environment and have low operation costs, and are therefore supposed as an alternative means of eliminating such contaminants from water [8,9]. Because of the discovery that certain microorganisms are able to grow by utilizing PAHs as a source of energy and carbon, bioremediation is now considered a valuable tool. Bioremediation also leads to the complete organic contaminant mineralization into carbon dioxide and water, or a transformation of complex organic contaminants into other, simpler compounds through certain biological agents, such as microorganisms [10,11].
Another advantage of employing microbial consortia is their large-scale production, since pure cultures are not often economically feasible due to high production costs, substrates, and biomass recovery. Additionally, many microorganisms are not isolated...