Fate of Pharmaceuticals , Personal Care Products , and Endocrine-disrupting 1 Chemicals in Water 2 3

Fate of Pharmaceuticals, Personal Care Products, and Endocrine-disrupting 1 Chemicals in Water 2 3 Arun Kumar 1 and Irene Xagoraraki 2 4 1 Department of Civil Engineering, IIT Delhi (arunku@civil.iitd.ac.in) 5 2 Department of Civil and Environmental Engineering, Michigan State University USA 6 7 Introduction 8 Pharmaceuticals (both prescriptionand non-prescription drugs) and personal care 9 products (combined and termed as PPCPs, hereafter) and endocrine-disrupting chemicals 10 (termed as EDCs, hereafter) have recently been identified as emerging organic contaminants in 11 environmental waters (Xagoraraki and Kuo, 2008; Sanderson et al., 2004; Christensen, 1998; 12 Schulman et al., 2002; Webb et al., 2003; Schwab et al., 2005; Bercu et al., 2008; Snyder, 2008; 13 Cunningham et al., 2009). Personal care products (PCPs) represent a group of chemicals, which 14 can be categorized based on their intended usages: (1) Cosmetics (e.g., triethyl citrate), (2) 15 Antimicrobial activity (e.g., triclosan), (3) Deodorizer (e.g., 1,4-Dichlorobenzene), (4) Fragrance 16 (e.g., 3-Methyl-1H-indole (skatol)), and (5) Flavorant (e.g., Camphor) (Stackelberg et al., 2004). 17 Endocrine-disrupting chemicals (EDCs) represent groups of chemicals which have been reported 18 to result in increased incidences of breast, prostate, and testicular cancers, reproductive disorders, 19 cognitive impairment, miscarriage, early puberty in girls, delayed puberty in boys, impaired 20 fertility in men, cognitive impairment, behavior abnormalities in children, etc. (Birklett, 2003; 21 Liu et al., 2005; Rahman et al., 2009). In general, these organic compounds can be categorized 22 in five categories: (1) Pharmaceuticals, (2) Steroids, (3) Alkylphenols, (4) Flame retardants, and 23 (5) Pesticides (Liu et al., 2005; Stackelberg et al., 2007). The presence of these organic 24 compounds in wastewater effluent and source water for drinking water utilities may have 25 implications on human and ecological health. 26 Water and wastewater treatment processes are capable of transforming PPCPs and EDCs, 27 but each compound responds differently to treatment, making it difficult to predict the fate of 28 these chemicals as a whole. A review of literature suggests that conventional water treatment 29 may effectively remove the majority of tested chemicals. However, certain compounds appear to 30 undergo treatment without transformation, thus requiring further treatment. Drinking water 31 oxidants, such as chlorine, ozone, and advanced ultraviolet (UV) oxidation have been shown to 32 degrade and transform a wide variety of PPCPs and EDCs. Chlorine and ozone are shown to 33 react with these emerging contaminants during water treatment and often results in the formation 34 of by-products that may or may not be harmful to humans and the environment. In most cases, 35 UV irradiation does not degrade emerging contaminants unless an advanced oxidation process 36 (AOP), such as H2O2/ozone is applied. Ozone appears to be the most effective at oxidizing 37 different classes of emerging contaminants present in waters. Predictive quantitative-structure38 activity-relationship (QSAR) models may be key to determining persistence of these chemicals 39 during drinking water treatment. However, the current state of knowledge does not provide clear 40 answers regarding potential human risks of exposure to emerging contaminants via water 41 consumption and/or recreational activities. 42