Removal of Polycyclic Aromatic Hydrocarbons from Polluted Water Using Constructed Wetlands: A Review

Abstract

During the last decades, Polycyclic Aromatic Hydrocarbons (PAHs) are detected in agricultural soils and water bodies at concentrations higher than permitted limits. The main sources of PAHs are fossil fuels, biomass burning, waste incineration, and pesticides. They harm aquatic ecosystems and organisms and pose a high risk to human health. For these reasons, several laws have been enacted to regulate the permitted concentration levels of PAHs in the environment and specifically, the wastewater discharged into aquatic ecosystems. Several methods for the removal of PAHs from wastewater exist which, although efficient, are not used extensively due to their high installation and operation cost. Constructed Wetlands (CWs) constitute an effective, practical, and low-cost option for PAHs removal from polluted waters. This paper focuses on the various treatment processes for the removal of PAHs. Research findings indicated that vertical flow CWs and hybrid systems are more effective in removing PAHs.