Maricor Arlos

University of Alberta | UAlberta · Department of Civil and Environmental Engineering and the School of Mining and Petroleum Engineering

Although the exposure assessment of wastewater-derived micropollutants via chemical, bioanalytical, and modeling methods in environmental compartments are becoming more frequent, the whole-body burden (i.e. internal concentrations) in non-target organisms resulting from micropollutant exposure is rarely assessed. An understanding of the internal co...

Exposure assessment of pesticides has substantially improved over time, with methods that now include a combination of advanced analytical techniques and fate/transport models to evaluate their spatio-temporal distribution. However, current regulatory environmental risk assessment considers thresholds from laboratory studies completed under standar...

Decades of studies on endocrine disruption have suggested the need to manage the release of key estrogens from municipal wastewater treatment plants (WWTP). However, the proposed thresholds are below the detection limits of most routine chemical analysis, thereby restricting the ability of watershed managers to assess the environmental exposure app...

Organic micropollutants found in the environment are a diverse group of compounds that includes pharmaceuticals, personal care products, and endocrine disruptors. Their presence in the aquatic environment continues to be a concern as the risk they pose towards both the environment and human health is still inconclusive. Removal of these compounds f...

Using a novel liquid chromatography-tandem mass spectrometry method with large volume direct injection and quantitation via isotope dilution, we evaluated the presence of 55 organic micropollutants in wastewater effluents, and locations within the Bow River and Elbow River watersheds in and around the city of Calgary, Alberta, Canada. In addition t...

For over a decade, intersex has been observed in rainbow darter (RD) (Etheostoma caeruleum) populations living downstream wastewater treatment plants (WWTPs) in the Grand River, Ontario, Canada. To further our understanding of intersex development in adult male fish, the current study addressed three objectives: i) can intersex be induced in adult...

The selected battery of in vitro bioassays may be used to monitor exceedances of effect-based trigger (EBT) values in environments potentially receiving treated oil sands process-affected water.

Pesticides used in agriculture can end up in nearby streams and can have a negative impact on nontarget organisms such as aquatic invertebrates. During registration, bioaccumulation potential is often investigated using laboratory tests only. Recent studies showed that the magnitude of bioaccumulation in the field substantially differs from laborat...

In this study, we evaluated the effectiveness of UV-LED-irradiated TiO2 in removing 24 commonly detected PPCPs in two water matrices (municipal wastewater effluent and Suwannee River NOM–synthetic water) and compared their performance with that of ultrapure water. Relatively fast removal kinetics were observed for 29% and 12% of the PPCPs in ultrap...

Effluents from municipal wastewater treatment plants (MWTPs) are complex mixtures of chemicals including endocrine-disrupting compounds (EDCs) and 17α-ethynylestradiol (EE2). The objective of this study was to evaluate selected responses of two fish species, in two different years, exposed in situ to MWTP effluent. Biological markers of exposure (p...

Removal of natural organic matter (NOM) in drinking water is an important objective imposed by water utilities due to plant operational problems, taste and odor issues. Photocatalysis using titanium dioxide (TiO2) has been increasingly explored in water treatment studies as a potential technology to remove NOM, with most studies employing 365 nm UV...

The combination of photocatalysis and biodegradation was investigated for the removal of nine selected pharmaceuticals as a means to reduce loadings into the environment. The combined process, consisting of a resource efficient mild photocatalysis and a subsequent biological treatment, was compared to single processes of intensive photocatalysis an...

The presence of pharmaceuticals and personal care products (PPCPs) in water remains a concern due to their potential threat to environmental and human health. Advanced oxidation processes (AOPs) have been receiving attention in water treatment studies to remove PPCPs. However, most studies have been focused on pure water containing a limited number...

The presence of pharmaceutical and personal care products (PPCPs) in aquatic systems has been a growing cause for concern. Advanced oxidation processes such as UV/TiO2 (ultraviolet light/titanium dioxide) can break down PPCPs into smaller constituents, reducing the pharmaceutical activity. However, this process is limited by low photonic efficiency...

In this study, the estrogenicity of two major wastewater treatment plant (WWTP) effluents located in the central reaches of the Grand River watershed in southern Ontario was estimated using population demographics, excretion rates, and treatment plant-specific removals. Due to the lack of data on estrogen concentrations from direct measurements at...

Research on the use of titanium dioxide (TiO2) for water treatment has expanded to include the degradation of pharmaceuticals and personal care products (PPCPs). PPCPs are typically introduced in aqueous solutions during TiO2 photocatalysis experiments using a water-miscible carrier solvent (e.g. methanol) to improve their solubility; however, carr...

Semiconductor photocatalysis such as ultraviolet/TiO2 (UV/TiO2) can be used in environmental remediation. It is an advanced oxidation process that can degrade organic contaminants through redox reactions. Unmodified TiO2 can only generate electron-hole pairs in the UV range so it has limited efficiency. Highly efficient materials are required for t...

Intersex in fish downstream of municipal wastewater treatment plants (MWWTPs) is a global concern. Consistent high rates of intersex in male rainbow darter (Etheostoma caeruleum) have been reported for several years in the Grand River, in southern Ontario, Canada, in close proximity to two MWWTPs. The larger MWWTP (Kitchener) recently underwent upg...

The occurrence of organic micropollutants (OMPs) in source waters has been associated with upstream discharges from municipal wastewater treatment effluents and runoff from agricultural and urban areas. Of emerging concern are pharmaceuticals, personal care products, pesticides and industrial chemicals that comprise the majority of the current...

Organic contaminants and corrosion in water treatment effluents are a current global problem and the development of effective methods to facilitate the removal of organic contaminants and corrosion control strategies are required to mitigate this problem. TiO 2 nanomaterials that are exposed to UV light can generate electron-hole pairs, which under...

TiO2 nanowire membranes are multifunctional in that they provide liquid separation of contaminated water and treated water and the ability to oxidize or degrade organic pollutants. TiO2 nanowires exhibit greater photocatalytic efficiency compared to bulk materials due to the high surface area and size effects in the quantum scale. In this work, TiO...

Endocrine disruption and high occurrences of intersex have been observed in wild fish associated with municipal wastewater treatment plant (WWTP) effluents in urbanized reaches of rivers around the globe. These reproductive effects have often been attributed to the presence of estrogen receptor agonists in effluents. However, recent studies have is...