Analysis of some pharmaceuticals in municipal wastewater of Almadinah Almunawarah

The chemical pollution of water resources is a major challenge facing the humanity in this century. Pharmaceuticals and personal care products (PPCPs) are a group of emerging environmental chemical pollutants distinguished by their bioactivity and high solubility. They may also cause health complications to humans and living organisms. Pharmaceuticals enter the environment, mainly via wastewater and can eventually reach the surface and ground water. Despite this, PPCPs received less attention as environmental pollutants than other chemical pollutants (e.g. heavy metals and pesticides). The purpose of this work was to investigate the presence of some of the most frequently dispensed drugs for the residents of Almadinah Almunawarah, Saudi Arabia in the municipal wastewater before and after treatment. For this purpose, wastewater samples were collected biweekly from the city’s sewage treatment plant for a period of 4 months and analyzed the targeted drugs using tandem LC–MS. Out of the 19 investigated drugs, 5 pharmaceuticals have been found in concentrations greater than the limit of detection in both the influents and effluents of the sewage treatment plant. As expected, the concentrations of investigated pharmaceuticals in the wastewater were found to be low. These drugs and their average concentrations (in ng mL−1) in the influents were: acetaminophen (38.9), metformin (15.2), norfluoxetine (7.07), atenolol (2.04), and cephalexin (1.88). Meanwhile, the effluents contained slightly lower levels (in ng mL−1) than those of influents: acetaminophen (31.2), metformin (3.19), norfluoxetine (7.25), atenolol (0.545), and cephalexin (1.53). The results of this study supported by many other investigations indicate the inefficiency of current conventional wastewater treatment protocols in eliminating such a group of active and potentially hazardous pollutants from the wastewater.