Presence of endocrine disrupting chemicals in sanitary landfill leachate, its treatment and degradation by Fenton based processes: A review

Various studies concerning sanitary landfill leachate (SLL) characteristics and toxicity identified the presence of endocrine disrupting chemicals (EDCs). A review of the detected EDCs in SLL was performed, in which the 12 most frequent EDCs identified in sanitary landfill sites over the world were ranked: BPA, DBP, DEHP, DEP, NP, BBP, DOP, DMP, 4OP, DiBP, DTBP and nicotine. The presence of these compounds is related to the activities on the dumping site, especially by the presence of plastic and personal care products, insecticides and cleaning agents in the waste bulk. Many diseases in human and animals have been associated with exposure to EDCs, as examples can be cited: disorder in metabolic processes that might end in diaseases, reduction of fertility, bioaccumulation and a high cancer potential. Among the treatment strategies applied to SLL degradation, processes based on Fenton reaction have received increasing attention due to its non-selective oxidation performed by hydroxyl radicals ((OH)-O-center dot). Thus, they are able to oxidize/mineralize compounds which are not removed in conventional wastewater treatments. Degradation pathways and byproducts produced after the oxidative process may provide important information around the applicability of these techniques. Integrated treatments are also studied to obtain biosafety of treated wastewater samples. For the SLL treatment, the most employed strategy coupled to Fenton-based processes is the biological oxidation. The integration strategy relies on the SLL characteristics, being two modalities allowed: Fenton-based processes followed by biological systems or the opposite one. Future researches are needed to advance our understanding of the behavior of EDCs in human and animals bodies, as well as its critic concentrations. Also, there still is a lack of research regarding the degradation pathway of EDCs by (OH)-O-center dot in a SLL matrix, the ecofriendly disposal of iron sludge, the handle of the chemical solution wastes and the economic aspects of these treatments in order to meet a large scale application of this technology. Therefore, these topics have been discussed in this review article. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.