Contaminants of emerging concern in Sharjah wastewater treatment plant, Sharjah, UAE

The presence and fate of contaminants of emerging concern (CECs) in wastewater have received growing attention due to their potential impacts on human health and the environment. In this study, the authors assessed the presence of CECs in the influent and effluent of the Sharjah wastewater treatment plant (SWWTP), a conventional activated sludge system, over a 1 year period. Sharjah is the capital city of the Emirate of Sharjah in the UAE. Characterisation of the CECs required development of elaborate analytical techniques for detection and quantification of CECs at the nanogram per litre level. A total of 57 CECs were detected and identified, of which ten pharmaceuticals, including seven antibiotics, an analgesic/antipyretic medicine, a b-blocker and an antipsychotic drug were quantified. The measured concentrations of the ten quantified pharmaceuticals were in the tens to hundreds of nanograms per litre, except for acetaminophen, which reached micrograms per litre levels. The quantified CECs in the effluent were 4-69% of their levels in the influent, indicating apparent removals in the range 31-97%. This study is the first one on the presence and removal of CECs in the SWWTP and contributes essential literature on the subject in Sharjah and the region.