Date of Award
Master of Engineering Science
Civil and Environmental Engineering
Dr. Ernest K. Yanful
Dr. Saad Y. Jasim
Studies have reported almost ubiquitous presence of endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs) in the aquatic environment globally. Many of these compounds have been documented to be detrimental to aquatic flora and fauna which have raised concerns regarding their potential health impacts on humans. Humans are unwittingly and indirectly exposed to EDCs and PPCPs as these emerging contaminants can easily flout conventional drinking water treatment processes. Lake Huron, despite being a major drinking water source for many communities around the Great Lakes area, remains largely unexplored in terms of assessing EDCs and PPCPs contamination. The current study thus focuses on the occurrence of selected EDCs and PPCPs in Lake Huron Water and their removal using O3/H2O2 based pre-coagulation advanced oxidation process (AOP). Raw water, collected from a drinking water intake on Lake Huron near Ontario and spiked with nine target EDCs and PPCPs at environmentally relevant concentrations, was treated in a dual train pilot scale treatment plant to achieve finished water turbidity less than 0.1 NTU. Poly-aluminum chloride (PAC1) was used as coagulant for the coagulation treatment during the study. Pre-coagulation AOP was applied on one side of the pilot plant. An O3 dose of 2.0-2.3 mg/L and 0.2 mg/L of H2O2 were applied. Solid phase extraction followed by LC-MS/MS, using electrospray ionization in both positive and negative modes was used to analyze the target micropollutants. Results show that pre-coagulation AOP can efficiently reduce the number of particles in finished water compared to the conventional treatment process. Also, improved filtered water turbidity was achieved during all the runs following AOP treatment. Sharp decline in ultraviolet absorbance at 254 nm (UV254) was observed right after AOP while only minimal overall decrease in dissolved organic carbon (DOC) was achieved. This indicates that the pre-coagulation AOP treatment did not mineralize organic carbon but probably formed intermediate products.
Atrazine, carbamazepine and fluoxetine were detected in raw Lake Huron water on at least four occasions at mean concentrations lower than 60 ng/L. None of the target chemicals showed any significant removal following conventional coagulation, sedimentation and filtration processes. Most of the target pollutants plummeted to concentrations below the method detection limit following AOP. However, ibuprofen and atrazine were consistently showing resistance to the applied doses during the study. No significant improvements in removals were observed following coagulation and filtration process preceded by AOP. The findings of the study suggest that certain EDCs and PPCPs are present in Lake Huron water. It also indicates that the majority of Canadian Drinking water treatment plants, since they employ only conventional coagulation and filtration processes, will be not be able to remove EDCs and PPCPs contamination, if these compounds are present in raw drinking water sources.
Rahman, Mohammed Feisal, "Removal of Endocrine Disrupting Compounds (EDCs) and Pharmaceuticals and Personal Care Products (PPCPs) from Drinking Water" (2009). Digitized Theses. 3921.