Cross-Contamination of Residual Emerging Contaminants and Antibiotic Resistant Bacteria in Lettuce Crops and Soil Irrigated with Wastewater Treated by Sunlight/H2O2.
The sunlight/H2O2 process has recently been considered as a sustainable alternative option compared to other solar driven advanced oxidation processes (AOPs) in advanced treatment of municipal wastewater (WW) to be reused for crop irrigation. Accordingly, in this study sunlight/H2O2 was used as disinfection/oxidation treatment for urban WW treatment plant effluent in a compound parabolic collector photoreactor to assess subsequent cross-contamination of lettuce and soil by contaminants of emerging concern (CECs) (determined by QuEChERS extraction and LC-QqLIT-MS/MS analysis) and antibiotic resistant (AR) bacteria after irrigation with treated WW. Three CECs (carbamazepine (CBZ), flumequine (FLU), and thiabendazole (TBZ) at 100 μg L(-1)) and two AR bacterial strains (E. coli and E. faecalis, at 10(5) CFU mL(-1)) were spiked in real WW. A detection limit (DL) of 2 CFU mL(-1) was reached after 120 min of solar exposure for AR E. coli, while AR E. faecalis was more resistant to the disinfection process (240 min to reach DL). CBZ and TBZ were poorly removed after 90 min (12% and 50%, respectively) compared to FLU (94%). Lettuce was irrigated with treated WW for 5 weeks. CBZ and TBZ were accumulated in soil up to 472 ng g(-1) and 256 ng g(-1) and up-taken by lettuce up to 109 and 18 ng g(-1), respectively, when 90 min treated WW was used for irrigation; whereas no bacteria contamination was observed when the bacterial density in treated WW was below the DL. A proper treatment time (>90 min) should be guaranteed in order to avoid the transfer of pathogens from disinfected WW to irrigated crops and soil.
Department of Civil Engineering, University of Salerno , Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy.
Giovanna
G
Ferro
Plataforma Solar de Almería-CIEMAT, Carretera Senés km 4, 04200 Tabernas, Almería, Spain.
María I
MI
Polo-López
CIESOL, Joint Centre of the University of Almería-CIEMAT , La Cañada de San Urbano, 04120 Almería, Spain.
Ana B
AB
Martínez-Piernas
Plataforma Solar de Almería-CIEMAT, Carretera Senés km 4, 04200 Tabernas, Almería, Spain.
Pilar
P
Fernández-Ibáñez
CIESOL, Joint Centre of the University of Almería-CIEMAT , La Cañada de San Urbano, 04120 Almería, Spain.
Ana
A
Agüera
Department of Civil Engineering, University of Salerno , Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy.
Luigi
L
Rizzo
D057914:Agricultural Irrigation; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D018556:Crops, Agricultural / Q000382:microbiology; D004352:Drug Resistance, Microbial / Q000187:drug effects / Q000528:radiation effects; D016983:Enterococcus / Q000187:drug effects / Q000528:radiation effects; D004926:Escherichia coli / Q000187:drug effects / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D018545:Lactuca / Q000382:microbiology*; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D018515:Plant Leaves / Q000382:microbiology; D012987:Soil; D013472:Sunlight; D062065:Wastewater / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis*
D006861:Hydrogen Peroxide; D012987:Soil; D062065:Wastewater; D014874:Water Pollutants, Chemical