Pharmaceuticals and other chemicals of emerging concern in leachate from a landfill and sludge storage facility

Abstract: The occurrence of 86 chemicals of emerging concern (CECs) (including pharmaceuticals, parabens, per- and polyfluoroalkyl substances, pesticides, stimulants, an isoflavone and an industrial chemical) was investigated in this study at Hovgården, a waste facility in Uppsala (Sweden). The selected CECs were analysed using solid phase extraction, sludge extraction and ultra-high pressure liquid chromatography coupled to mass spectrometry. The main aim was to get a broader understanding regarding the occurrence of pharmaceuticals in leachate (which pharmaceuticals that were present in what quantities and where) at Hovgården, particularly from a landfill and sludge storage facility. The occurrence of pharmaceuticals most likely originated from leachate formed in sludge from the old landfill’s final cover and from the sludge storage facility. 45 out of the 56 analysed pharmaceuticals were detected in the landfill leachate, at mean concentrations ranging from 1.1 ng/L (fexofenadine and tramadol) to 4900 ng/L (erythromycin). The total mean concentration of pharmaceuticals in leachate received from the old landfill’s final cover (23 000 ng/L) was 45 – 49 times greater than the active landfill. 48 pharmaceuticals were detected in leachate from the sludge storage facility, at mean concentrations ranging from 1.3 ng/L (climbazole) to 3000 ng/L (desvenlafaxine). The total mean concentration of pharmaceuticals ranged from 1500 ng/L (leachate from contaminated soil) to 16 000 ng/L (combined leachate from sludge and contaminated soil). The total mean concentration of pharmaceuticals decreased by approximately 8.1 % after the wastewater treatment plant’s (WWTP’s) last treatment step compared to the WWTP’s influent. The WWTP’s recipient had the lowest total mean concentration of pharmaceuticals (240 ng/L) of all sampling points. It was not possible to determine whether the obtained results regarding the occurrence of pharmaceuticals were reliable, as this was the first time that this was evaluated at Hovgården. Further screenings were therefore recommended, by repeating this study, before implementing additional treatment methods. It was also recommended to include a risk characterization, to evaluate and assess whether the obtained concentrations may be harmful for the receiving environment. In addition, the presence of CECs in waste (and consequently at waste facilities) is due to our consumption and disposal of CECs. This includes our overuse/misuse of pharmaceuticals with shown consequences for the (aquatic) environment that indirectly could harm the human health, such as increased antimicrobial resistance. The occurrence of CECs in sludge and sewage systems could thus be minimized by also increasing the public’s awareness about the consequences of our actions regarding CECs.