Seminars and thesis defenses
Anti-cancer drugs removal from wastewater effluents
By Raphaël Janssens (iMMC / IMAP)
The presence of anti-cancer drugs in European surface waters indicates that currently applied wastewater treatments are not effective for the removal of persistent compounds. In this work, three advanced oxidation processes (UV, UV/TiO2 and UV/H2O2) were applied first on laboratory grade water and then on real secondary effluent spiked with four anti-cancer drugs (5-fluorouracil, capecitabine, cyclophosphamide and ifosfamide) at 500 µg/L. Direct photolysis in laboratory grade water led to degradation rates of 0.191 ± 0.007 1/min for 5-fluorouracil, 0.078 ± 0.005 1/min for capecitabine, 0.047 ± 0.008 1/min for cyclophosphamide and 0.039 ± 0.004 1/min for ifosfamide. Improved removal performances were observed when catalyst was brought in suspension: capecitabine (+37%), cyclophosphamide (+35%) and ifosfamide (+32%). In wastewater effluent, drug degradation rates were reduced by 4 to 6 times probably caused by catalyst aggregation. Among the three investigated oxidation processes, UV/H2O2 scored best in term of COD abatement and electrical energy per order. Further results confirmed this tendency as 5 times lower operating and environmental costs were required for the treatment of wastewater effluents by UV/H2O2 in comparison to photocatalysis. This technology stands thus as promising barrier against anti-cancer drugs discharge in surface waters.