Potential of the Constructed Wetlands and the Earthworm-Based Treatment Technologies to Remove the Emerging Contaminants: A Review

Abstract

Emerging contaminants (ECs), especially pharmaceuticals and personal care products (PPCPs), that are present in aquatic and soil matrixes, have become a major concern for the competent authorities, because they are persistent and pose potential threats to human health, aquatic life, and the soil ecosystem. As an environmentally sustainable and economical EC remediation technology, constructed wetlands (CWs) and vermifiltration (VF) have become popular for treating wastewater and vermicomposting (VC) has gained the attention of the researchers as a sewage sludge or solid waste treatment technology. Although extensive literature is available on the potential of CWs for the remediation of ECs, a review of earthworm-based EC removal technologies has not been performed, to the best of the authors’ knowledge. Therefore, this paper aims to review the potential of all the aforementioned natural EC remediation technologies. CWs and VF could emerge as suitable alternatives to conventional wastewater remediation methods to eradicate ECs, and VC has the potential to substantially eliminate ECs from organic solid wastes. In addition, risk assessments suggest that these technologies are more efficient in expurgating the level of toxicity imposed by ECs on the ecosystems that receive them than the conventional treatment methods.