ABSTRACT

Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and sunlight degradation processes. POPs are known to persist in the environment for long periods due to such properties and can thus be capable of long-range transportation between lands, rivers, and oceans. Such compounds will bioaccumulate in seafood and animal tissues and subsequently become biomagni’ed in food chains and ultimately impact human health and the environment. Many POPs are pesticides such as DDT, whereas other compounds such as PCBs

CONTENTS

Introduction ......................................................................................................... 145 Background on POPs and CECs ....................................................................... 147

Agricultural and Industrial Compounds .................................................... 148 Hormones and Antibiotics ............................................................................ 148 Other PhACs and PCPs ................................................................................. 149

Current Information on the Removal of POPs and CECs in POSTW ......... 149 Other Treatment Methods to be Incorporated into POSTWs ....................... 158

Activated Carbon Adsorption ...................................................................... 158 Ozone Treatment ............................................................................................ 167 Reverse Osmosis ............................................................................................. 177 Biological Aerated Filters with Active Carbon Coupled with Ozone Treatment (BAC) ....................................................................... 177

Conclusion ........................................................................................................... 178 References ............................................................................................................. 179

are used in industrial applications and in the production of a wide range of products. In the past few years, pharmaceutically active compounds (PhACs) and personal care products (PCPs) have been discovered in various environments and water sources. Some of those compounds have been linked to ecological impacts at concentrations of less than 1 ng/L. These PhACs and PCPs were eventually grouped with other emerging contaminants, such as nitrosamines from disinfection by-products (DBPs), metals, and other new additions of compounds, such as endocrine-disrupting compounds (EDCs), and are collectively referred to as compounds of emerging concern (CECs) (Drewes et al. 2006, WERF 2007). It has been reported that certain synthetic compounds, such as detergents and pesticides, and natural compounds, such as sex hormones, can affect the balance of normal hormonal function in animals. These substances are classi’ed as EDCs and have been linked to a variety of adverse effects in humans and wildlife (Snyder et al. 2007). The U.S. Environmental Protection Agency (U.S. EPA) refer to EDCs as exogenous agents that interfere with the “synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body which are responsible for the maintenance of homeostasis, reproduction, development, and/or behavior” (U.S. EPA 1996). In humans, studies have linked the exposure of mothers to phthalates such as diethylhexyl phthalate to adverse impacts in their children, including lowered testosterone levels in boys (U.S. Department of Health and Human Services 2008). EDCs are further classi’ed as thyroidal (compounds with direct or indirect impacts to the thyroid glands), androgenic (compounds that mimic or block natural testosterone), and estrogenic (compounds that mimic or block natural estrogen) (Snyder et al. 2007). Recently, the illegal replacement of palm oil with diethylhexyl phthalate and diisononyl phthalate (plasticizers) by some food-grade manufacturers in Taiwan has caused huge product recalls in numerous food, drink, and medicinal formulations in Taiwan and surrounding trading markets in June of 2011.