emerging issues

BY

LO R IEN

J.

FO NO

A ND

H .

S TEP H EN

MC D O NALD

One way compounds of emerging concern can enter the environment is through wastewater treatment plant effluent.

Emerging compounds: A concern for water and

wastewater utilities A LT H O U G H M O R E R E S E A R C H N E E D S TO BE CONDUCTED REGARDING THE EFFECTS OF COMPOUNDS OF EMERGING CONCERN, I T I S L I K E LY T H AT T H E S E COMPOUNDS REPRESENT THE NEXT R E A L M O F R E G U L AT O R Y C O N C E R N .

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ater utilities have come under increasing scrutiny as the agencies responsible for controlling human exposure to pharmaceuticals, endocrine-disrupting chemicals, and other compounds of emerging concern (CECs) in drinking water. For example, a recent investigation by the Associated Press (Donn et al, 2008) reported on the presence of pharmaceuticals in the drinking water of 24 major US metropolitan areas. This report prompted public concern and put additional pressure on water utilities to respond to what was presented as a threat to public health. Most CECs are likely benign to humans at the concentrations detected in the environment and in drinking water. They continue to be of concern, however, because some of the compounds that have been detected are endocrine disrupting chemicals (EDCs). EDCs can have effects on the human endocrine system at extremely low concentrations, although no risk to humans has been demonstrated from exposure to EDCs in drinking water. EDCs have, however, been implicated in adverse effects in aquatic organisms that are exposed to wastewater in the environment. There is also evidence that some CECs that are not EDCs demonstrate toxicity with more traditional endpoints toward aquatic organisms (such as growth inhibition or change in behavior), even at enviornmentally relevant concentrations. There is also evidence that some CECs that are not EDCs demonstrate toxicity with more traditional endpoints toward aquatic organisms, even at environmentally relevant concentrations.

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2008 © American Water Works Association

Although more research needs to be conducted regarding the effects of CECs on human and aquatic health, it is likely that these compounds represent the next realm of regulatory concern and that their removal will drive the research agenda and the selection of water and wastewater treatment processes in the future.

CECs ARE UBIQUITOUS DOWNSTREAM OF WASTEWATER DISCHARGES Although many CECs have been present in the environment for decades, concern about their possible effects on humans and wildlife is being driven by improved analytical techniques that are able to detect them at increasingly lower concentrations. In general, these compounds are present at trace concentrations (i.e., parts per trillion or less) in complex mixtures. CECs encompass a large number of compounds (Table 1). Compounds can be grouped either by their intended use—such as pharmaceutical products or surfactants—or by their potential environmental or human health effects. For example EDCs, which interfere with human or animal hormonal function, sometimes even at very low levels, comprise trace constitu-

TABLE 1

ent classes such as pharmaceuticals, personal care products, detergent metabolites, plasticizers, brominated flame retardants, and pesticides. Additionally, individual compounds within a class can have significantly different toxicities and removal rates within wastewater treatment plants (WWTPs) and in the environment. CECs have been detected in surface waters and groundwater downstream or downgradient of wastewater discharges. Much of the early occurrence survey work was conducted in Europe—particularly Germany and Switzerland—where high population densities and low per capita water use result in relatively high concentrations of CECs in wastewater and receiving waters. Even illegal drugs such as cocaine are detectable in some surface waters that are affected by wastewater (Zuccato et al, 2005). There has been, and continues to be, a significant amount of investigation into the presence of CECs in the environment in North America. For example, Kolpin and colleagues (2002) at the US Geological Survey (USGS) performed a survey of trace organic contaminants in US surface waters and detected 82 of 95 individual CECs on their analyte list,

with low levels detected almost d in alm most aall ll samples. As a testamentt to the attenatttenen tion this topic has been attracting, en attr ract ctin ng, the resulting article was th the he mo most st downloaded article everr publ published blishe bl l heed in n Environmental Science an and Technolnd T ecch chno ollogy (Kolpin et al, 2002). 2). David Sedlak, a professor ofeesso or aatt tthe hee h University of California ia at at Berkeley Berk kel eley ey and the principle investigator stiggattor of of an an Awwa Research Foundation–spondati tion n–sspon po onnsored occurrence survey vey of o f pharp harhaa rh maceuticals in wastewater wateer effluent, effl flue ueen ntt, has been researching the he fate fat atee and and an transport of CECs over ver er the t h e past past decade. “At this point, not in n t, it’s it s n ot ot whether we can find them. them em. We We see seeee them everywhere. The hee question q uest stio st on now is whether they’re y’re r having haa v in ng adverse effects on wildlife dlif ife populapo opu ula lations, and what can wee do about abo ab ou ut it,” Sedlak said.

CECs IN WASTEWATER R ADVERSE ADVERSELY SELY SE Y AFFECT AQUATIC ORGANISMS ANISMS There has been growing wing ng at attention tten nti tio tio on n during the past several al years year ye arss from from m the public and the scientific and cien enti tiffi f i c an nd wastewater communities the nitii e s on n th he potential ecological effects feccts of trace trac acce constituents. For example, during mp ple, e,, dur urrin ng the past two years, significant media nifiican an nt me edia coverage was given to reports that o re epo orts rts th hat at up to 100% of the malee ssmallmouth malllmo ma out uth bass in some sections of thee ChesaChe hesa sa a-

Trace constituents in wastewater

Class of Compound Pharmaceuticals

Typical Concentration in Effluent

Potential Ecological or Human Health Effects

Up to 1 µg/L

Endocrine disrupting

Antibiotics, painkillers, caffeine, birth-control pill, antiepileptics Soaps, fragrances, triclosan

Examples

Personal care products

Up to 1 µg/L

Bioaccumulative, endocrine disrupting

Detergent metabolites

Up to 180 µg/L

Bioaccumulative, endocrine disrupting

Ocylphenol, nonylphenol

Plasticizers

Up to 10 µg/L

Weakly endocrine disrupting

Phthalate esters, bisphenol A

Perfluorooctane surfactants

Up to 1 µg/L

None at environmentally relevant concentrations

Stain-resistant coating for clothing and furniture

Brominated flame retardants

Up to 30 mg/L

Bioaccumulative, suspected endocrine disruptors

Polybrominated diphenyl ethers

Up to 1 µg/L

Carcinogenic

N-nitrosodimethylamine

Disinfection by-products

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REPRODUCED WITH PERMISSION FROM ENVIRONMENTAL HEALTH PERSPECITVES

Intersex Int ntersex fish have been found downstream f nd do fo fou of wastewater of was w te ewater discharges worldwide. worldw wide id . This figure illustrates illlu usttra rat a es fis fish testes that also o ccontain ova (Nash et al, 2004). ((Na sh e

peake p eaak ke Bay B y watershed Ba watter wa are intersex ((Associated (A Asssoc ocia i teed Press, 2006). Wildlife to CECs and Wild Wi ldlife fee are are exposed exp EDCs streams ED E DCs Cs iin n eeffluent-dominated ffluen nt-d byy eati or b or eeating ea ati t ng ng plants plan nts or animals in which tthese th hese substances substancces have ha bioaccumulated. Aquatic organisms A Aq qu qu ua atic or o ga anism ms have a greater risk than tth haan n humans human a s because beca be c u they have greater Although eexposure. ex xposu sure. Al lth tho ou many of these undergo ccompounds co omp mpo poun ounds nds un nd u derg natural attenuabecause they ttion ti io on n iin n the the environment envirron being constantly discharged, aare ar r e be b ingg co in con n sta organisms or o rga ga ism gani smss th that at aare re exposed to them “pseudopersistence.” eexperience ex xpe perriien e ce a “ps pseu Recent Reece R cent n research resea arch has examined the eeffects ef ffe fect c s off CECs CEC C ECss and an EDCs on wildlife both bo b otth h in in the t e lab th lab and an in the field. In many m ma an nyy sspecies peccies pe es this this rresearch has shown a causal cau ca aus usal al relationship rellat ation nsh between expohuman ssure su ure re tto o hu h m n aand synthetic horma mones, plasticizers, and detergent mo m on neess,, p l st la stic i ize metabolites the induction of an me m etta ab bo olite liitees an and d th egg protein eg gg pr pro otei ein in nm male fish, for example. found downstream of IIntersex Int In nters terssex e ffish ish fo foun WWTPs have been W WT TP Ps h ave be een linked to estrogenicity wastewater ni ici c ty iin nw astew wate discharges (Harries 1996). rie ri es eett al, 1 es 996).. Most Most significant, Mo significcan in a seven-year study Experimental Lakes st tu ud d y in the E xp Ontario the popuArea iin Area n northern no ortherrn O off fa fathead minnow exposed to llation la tio ti on o athead dm a low l w but lo but constant bu constan concentration of hormone found th the he ho ormo one fo oun in birth control pills ultimately (Kidd et al, pi p ill llss ul ltim mately ccollapsed ol 2007). Although these specific results 2 20 007). Alt though h th cannot extrapolated ca ann nott be immediately immeedi other to o to t eerr species th s peci ciee s and watersheds, cause for tthere th heerre is i ca ause se fo or concern. 5522

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THE SPOTLIGHT ON WATER UTILITIES IS DRIVEN BY HUMAN HEALTH CONCERNS Potential human health effects resulting from exposure to CECs are harder to detect than effects on wildlife. Humans are exposed to pharmaceuticals and endocrine-disrupting chemicals through various routes. For example, fat-soluble compounds such as flame retardants or PCBs can be consumed by eating aquatic animals in which they have bioaccumulated, and water-soluble compounds such as most pharmaceuticals for humans can be consumed in drinking water. This latter route is of concern to the drinking water industry. Research is just beginning to address questions about effects of chronic low-level exposure, including possible synergism and other toxicological factors associated with these compounds. It is difficult to predict the effects of chronic exposure to extremely low concentrations of a contaminant; generally, tests are done with higher concentrations than occur in drinking water, using other mammalian species, and the effects are extrapolated to lower concentrations using a dose–response curve. A safety factor is then applied to account for the differences between humans and the test species. Some toxicity studies are conducted by exposing human tissue cultures in vitro to the compounds being examFONO & MCDONALD

2008 © American Water Works Association

ined. Neither of these types of experiments provides conclusive evidence about the human health effects of exposure to parts-per-trillion levels of pharmaceuticals in drinking water. The constituents of greatest potential concern to humans are the E D C s m e n t i o n e d p r e v i o u s l y, because of possible effects at very low concentrations. They also pose a disproportionate threat to fetal development and young children because they interfere with normal developmental chemical signals in the body. Therefore, it is not just the level of exposure of EDCs that cause concern, it is also the timing of the exposure during the development of humans and animals. The potential human health effects of EDCs are being studied by many groups, including the US Environmental Protection Agency (USEPA). The endpoints of exposure to pharmaceuticals and EDCs in water that are being considered by researchers include endocrine system effects, neurological problems, reproductive and developmental abnormalities, and cancers. Many researchers point out that the quantity of estrogens that may be consumed in reclaimed water is tiny compared with phytoestrogens and estrogenic hormones naturally present in the human diet. In fact, risk assessments that have been performed on drinking water to date

have not shown an unacceptable risk to humans (Snyder, 2007). However, most researchers currently agree that there are many unknowns regarding possible synergistic effects and long-term chronic exposure to low levels of complex mixtures of these compounds.

rate of the compounds as well as their behavior and effects in the environment once introduced. In Canada, a similar requirement is under consideration. The United States has already banned the use of some known endocrine disruptors, such as PCBs, DDT,

A

lthough many of these compounds undergo natural attenuation in the environment, because they are being constantly discharged organisms that are exposed to them experience a “pseudopersistence.”

Regulations can control the input of CECs into the environment and drinking water in two ways: • by restricting which chemicals can be marketed and therefore make their way into the waste stream and • by setting wastewater effluent and drinking water concentration limits for individual compounds or bulk parameters such as estrogenicity. So far, regulators have been more inclined to pursue the first option because toxic effects can more readily be shown in the parent product, rather than diluted in wastewater or drinking water. European countries are further along than the United States in phasing out endocrine disruptors. Norway, for example, has banned the production, import, distribution, and most uses of nonylphenol and octylphenol ethoxylates. These are surfactants that have been shown to contribute significant estrogenicity to rivers downstream of industrial wastewater discharges. Additionally, the European Union requires the submission of Environmental Risk Assessments (ERAs) to gain market approval for new pharmaceuticals. These ERAs focus on the removal

and chlordane. However, these compounds were banned because of their carcinogenic effects rather than their estrogenic effects. In 1996, Congress passed new legislation requiring the USEPA to determine whether certain substances may have an effect in humans that is similar to effects produced by a naturally occurring estrogen or other such endocrine effects. In response, USEPA developed the Endo-

FIGURE 1 CEC removal during membrane filtration improves as pore size is reduced Colloidal particles Dissolved salts

Cryptosporidium and Giardia Bacteria

Viruses

100 Retention of Particle Size —%

REGULATORY REQUIREMENTS FOR CECs ARE ON THE HORIZON

crine Disrupter Screening ening and Testing Testin Te ng Advisory Committee (EDSTAC), tee (ED D STAC C ), whose members include clude representarepressentataatives of academia, industry, ind dus ustry, public pub p ub bliic health interests, water er providers, provid der e s, s, aand nd d various state and federal derral agencies. agen ncciies. In its 1998 final report, rep port, EDSTAC ED DSTA STAC ST AC recommended a priority-based ority ty-based ed d tiered tieere red screening system to evaluate ev val a uate te chemicheemi micals for endocrine-disrupting isru ruptingg effects. effe fecctts.. fe However, this program ram m has h s received ha reece ceiv eivveed d little funding, and the he past pa t 10 10 years years have seen little progress rogr gresss on n the th hee screening of suspected ted d EDCs. ED DC Cs. So far, neither thee USEPA nor U EP US EPA A n no or or regulators in other co countries have ountrie ies ha h vvee released any guidance about the ancc e ab b ou o t th he effects of relevant le levels off m most e ve v ls o mo o sstt trace constituents in n drinking drrin i kiingg water. wat ater. US regulatory action on at at the the federal fede dera ral level has been delayed until more ayeed unt ntill m ore research has been done because most onee b ecaause m ec ost os ost existing data on listed steed man-made maanmann-m madee ma chemicals focus on can cancer risks, nce cer risk ri isk sks, aand sks nd nd CECs are generally present pre resentt at at conco onncentrations too low w to o trigger tri r ggger concon ncerns about carcinogenicity. gen nic iciity. y. In response to the Associated Ass ssociate ted te d Press Presss Pres article on pharmaceuticals eutiica cals in in drinkdrrin d inkking water, a hearing on n “Pharmaceu“Pha “P haarm mac aceu uticals in the Nation’s Water: Watter er:: Assessing Asssessing ing in Potential Risks and nd d Actions Actio Ac o n s to to Address the Issue” wass held hel held d in n April Aprril il

Reverse osmosis

Nanofiltration

Ultrafiltration

Microfiltration

0 0

0.001

0.01

0.1

1.0

10.0

Size—µm CEC—compounds of emerging concern

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release of suspected endocrine disruptors to the environment to protect aquatic habitats. In the future, it is likely that drinking water criteria will be developed for some CECs. Therefore, master planning studies for both water and wastewater facilities would be advisable to address the possibility of new regulations when making long-term (10- to 20-year) plans.

Of the advanced treatment technologies, ozonation removes the greatest percentage of compounds of emerging concern, for the lowest unit cost.

SCIENTIFIC RESEARCH AND PILOT TESTING ARE LEADING TO CEC REMOVAL SOLUTIONS 2008 2 20 008 b by y th the Senate subcommittee on Transportation T ransp ansporrtaati tion Safety, IInfrastructure nfr frasttruc uctu turre SSecurity, and aan n d Water Wa terr Quality. Q Although not A lth t ou ugh no ot rresulting i immediate in imm m ediaate regulatory tto ory aaction, ction, ct n, tthis h hearthat ing demonstrates ing deemonstr t a the the issue the th iisssu suee has caught ca attention US senaaat tteentiion of U which ttors, orss, w hic ich h may ma provide impetus for regulatory developments. ffurther urrttheer re regu gullat US are beginning US statee regulators reg move to m to ovee ahead ov aheead with adopting criteah federal mandate to do rria, ia, a, aabsent a, b entt a fe bs Several states, such as Massachuso. Se so. so Sev veral st stat setts have adopted se ett ttss and a d California, an Calif Ca water w wa ater teer quality q al qu a itty criteria for perchlorrate, ra attee, a CEC CEC that th is found in rocket fuel ffu uel el and an nd other nd oth ther explosives that has been b be een en sshown sho hown n to interfere with fetal development de d eve v lo lopm pmentt aat extremely low concentrations. Massachusetts intends cce ent ntra r ti t on ons. s. M use process it developed to to u to se tthe he p pro regulate perchlorate to move ahead rre egu gula ate p ercch er with w wit wi ith eexamining xami mini n n possible limits for a and perllist ist s of 100 pharmaceuticals ph ha products. ssonal onal ccare are pr rod Other agencies, although not yet Oth her age enc water limits rready ead ady to sett drinking d ffor or CECs, CE ECs, are beginning to require they monitored in anticipatthat hat th hey be m off pos possible future requiretion o tion s si ments. the California m ment me ent n s. For eexample, xa Department D e parr tmen n t of Public Health updated its Groundwater ((CDPH) CD DPH H) upd da Recharge Reuse R eccharge Re eu Draft Regulations Criteria August 2008 to include C Cri riteriia in A u project-specific p pr roj ojec ectt-sp pec e ific monitoring require54 54

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ments for endocrine disruptors and pharmaceuticals as well as CEC indicator compounds or surrogates in recycled water and groundwater recharge projects. The link between CECs in wastewater and adverse ecological effects is stronger than is the link between CECs in drinking water and human health effects and therefore has attracted more attention for possible regulation at the federal level. The USEPA (2008) recently released a draft white paper concerning the development of criteria for CECs. In this document, USEPA acknowledges the difficulty of adopting criteria for constituents with nontraditional endpoints related to endocrine disruption and begins to detail a framework to address this challenge. Future regulatory action is likely as research progresses, and, once officially identified, industrial chemicals and personal care products that are strong endocrine disruptors will probably be phased out of use. In the meantime, wastewater treatment facilities could be regulated for FONO & MCDONALD

2008 © American Water Works Association

Both water and wastewater treatment can provide a barrier that prevents the introduction of CECs into drinking water. However, for the protection of aquatic life, the preferred barrier is removal during wastewater treatment. Although most wastewater treatment plants are not specifically designed to remove trace constituents, the majority of these compounds are removed at least partially during conventional wastewater treatment. One of the most effective ways of increasing the removal of trace constituents during biological wastewater treatment is to increase the sludgeretention time to at least 15 days or more. Under these conditions Clara and co-authors (2005) found that most pharmaceuticals, surfactants, and plasticizers are removed to below the limit of detection. Concentrations of human estrogens are reduced by 90–100% with high sludge-retention times. In fact, removal rates depend more on the sludge-retention time than on the treatment technology, because trace constituents are removed equally in an activated sludge process such as a membrane bioreactor. For treatment plants with excess capacity, sludge-retention times can be increased by changing operating procedures without additional capital investment. Several advanced treatment technologies have been shown to be effective for removing trace constituents from wastewater. Filtration through granulated activated carbon (GAC),

advanced oxidation, and membrane treatment have all been studied to determine how well they remove trace constituents. Table 2 provides a summary of the removal efficiencies for CECs by different technologies. An advanced oxidation technique that is being studied for removing trace constituents is the irradiation of filtered wastewater with ultraviolet (UV) light after hydrogen peroxide has been added. This process generates free hydroxyl radicals that react quickly and nonspecifically with organic constituents in wastewater. In a study by Rosenfeldt et al (2004), two common hormones in wastewater were more than 95% removed from lab water with a concentration of 15 mg/L hydrogen per-

TABLE 2

oxide and either a low- or mediumpressure UV lamp. Ozonation is often put forth as a good technique for oxidizing trace contaminants in wastewater. A lthough ozone reacts preferentially with some compounds depending on their structure, it can also react with natural organic matter to form hydroxyl radicals and indirectly oxidize a greater number of constituents. Hormones are among the compounds that react well with ozone, as do most pharmaceuticals that have been tested. Ozone is effective at oxidizing some of the most frequently detected trace constituents, such as carbamazepine (an antiepileptic drug), caffeine, cotinine (a nicotine metabolite), and atrazine (a pesticide).

With respect to advanced oxidation, both UV/peroxide and ozonation are good treatment technologies for trace constituents. Both, also provide disinfection for wastewater, and improve its aesthetic qualities. However, several analyses have shown that ozone can provide removal at a lower cost (Ternes et al, 2007). In general, trace constituent removal is poor during sand filtration. However, with chemical addition prior to sand filtration, Salveson et al (2007) showed that the increased particle size can improve removal to 70% for some of the more hydrophobic compounds such as hormones. This can be an economical treatment strategy for WWTPs that already practice sand filtration.

Summary of CEC removal by a suite of treatment technologies

= > 90% Removed = 40–70% Removed = < 40% Removed

Classification

AS

AC

BAC

03/AOPs

UV

Coagulation/ Flocculation

Softening/ Metal Oxides

NF

RO

Pesticides Industrial chemicals Steroids Metals Inorganics Organometallics Antibiotics Antidepressants Anti-inflammatory Lipid regulators X-ray contrast media Psychiatric control Synthetic musks Sunscreens Antimicrobials Surfactants/detergents Adapted from Snyder et al, 2003 AS—activated sludge. AC—activated carbon, BAC—biological activated carbon, CEC—compounds of emerging concern, NF—nanofiltration, O3/AOP—Ozone/advanced oxidation processes, RO—reverse osmosis, UV—ultraviolet irradiation

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In membrane filtration, water and wastewater are pushed through tiny pores at high pressure to reject particles that are not desired in the permeate. Microfiltration (MF) and nanofiltration (NF) have progressively decreasing pore sizes and require increasing pressure for operation, with reverse osmosis (RO) having the smallest pore size and the highest pressure. MF rejects relatively fewer compounds than NF or RO because

cost of advanced treatment can be counted in carbon dioxide emissions as well as dollars (Jones et al, 2007). Therefore, source control is being looked at as an alternative for reducing the concentrations of CECs in the environment and in drinking water. Although the potential for CEC reduction in wastewater is much smaller for some compounds through source control than through advanced treatment, it is an immediate step that can be taken by local

M

ost researchers currently agree that there are many unknowns regarding possible synergistic effects and long-term chronic exposure to low levels of complex mixtures of these compounds. most trace constituents are smaller than the MF membrane's pore size, although some hydrophobic compounds are excluded through adsorption. NF performs better than MF with most compounds because NF membrane pores are small enough to reject many compounds based on size, but NF is expensive. RO removes most compounds with a very high efficiency except for NDMA, which is small, polar, and behaves like a water molecule. However, although RO removes most constituents to below the limit of detection, its capital and operating costs are extremely high.

SOURCE CONTROL IS AN ATTRACTIVE OPTION FOR REDUCING EDCs IN THE WATER CYCLE Cash-strapped utilities may not have the means to implement advanced treatment to remove unregulated constituents from their wastewater or drinking water. Additionally, with recent focus on climate change and carbon footprints, the 5566

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governments and utilities that does not require facility upgrades or changes in operational procedures. Source control can include the following measures: • Pharmaceutical take-back programs to prevent the practice of flushing unneeded or expired pills. It is estimated that a maximum of 8% of pharmaceuticals are flushed down the toilet and that removing this source would lead to an approximately 9% reduction in surface water loading (Tischler et al, 2007). • Ecolabeling of household and personal care products to encourage consumers to choose products with nonpersistent, nontoxic ingredients. Regulatory oversight would be needed to allow products to claim ecofriendliness on their labels. • Reduction of over- and unnecessary medication. This has already been recommended to prevent the development of antibiotic-resistant bacteria and could also help reduce concentrations of CECs • Requiring ERAs for new pharmaceutical products and phasing out FONO & MCDONALD

2008 © American Water Works Association

persistent or toxic pharmaceuticals when there is another compound that could have the same benefit without a toxic effect. Thus far, source control efforts have focused on pharmaceutical take-back programs. Several states have initiated such programs with great success—as measured by the quantity of unused drugs that have been recovered. Although most drugs enter the water cycle via human excretion, these programs can remove a portion of the loading to WWTPs and have additional benefits such as reducing accidental prescription drug poisoning and misuse. Source control efforts require educational campaigns to inform and engage the public. Because the Southern Nevada Water Authority (SNWA) has led or been involved with much of the scientific work related to the low-level detection, treatment, and health effects associated with pharmaceuticals and EDCs in drinking water supplies, the agency has been at the forefront of communication about this topic. “By educating the public about the proper disposal of all types of chemicals—from household solvents and pesticides to unused pharmaceuticals—utilities are encouraging their customers to become stewards of both their water resources and the environment,” said J.C. Davis, the senior public information coordinator at SNWA. Source separation is another alternative that could be considered to reduce CECs in wastewater. The most feasible means of achieving this goal is to provide onsite advanced treatment to hospital wastewater, which is a significant point source of pharmaceutical discharges to wastewater treatment plants.

LOOKING AHEAD AND MOVING FORWARD Members of the public will continue to demand that the issue of CECs in the environment and in drinking water be addressed by their utilities, even in the absence of regulatory guidance. A coherent ap-

proach for treatment and control of CECs, as well as a communication strategy, is necessary to assure the public that the issue of pharmaceuticals in drinking water is being considered and addressed by their water purveyors and that aquatic life is being protected by wastewater dischargers. Clearly, there is the need for more research and continued research funding until the risks from CECs are understood and addressed. Shane Snyder, a scientist at the SNWA, who has contributed significantly to knowledge about the treatment and effects of CECs, emphasizes the need for continued research. “As a scientist, I recommend we focus on research related to health effects from trace pharmaceuticals with a lesser emphasis on occurrence, in order to determine whether there is in fact a problem to solve. The critical question we must address is not ‘Do they exist?’ but rather, ‘At what concentration are these compounds harmful to

REFERENCES Associated Press, 2006. Intersex Fish Are Found at High Rate in a Region. New York Times. Clara, M.; Strenn, B.; Gans, O.; Martinez, E.; Kreuzinger, N.; Kroiss, H., 2005. Removal of Selected Pharmaceuticals, Fragrances and Endocrine Disrupting Compounds in a Membrane Bioreactor and Conventional Wastewater Treatment Plants. Water Res., 39:19:4797. Donn, J.; Mendoza, M.; Pritchard, J., 2008. AP Prove Finds Drugs in Drinking Water. Associated Press, New York. Harries, J.E.; Sheahan, D.A.; Jobling, S.; Matthiessen, P.; Neall, P.; Routledge, E.J.; Sumpter, J.P.; & Tylor, T., 1996. A Survey of Estrogenic Activity in United Kingdom Inland Waters. Envir. Toxicol. & Chem., 15:11:1993. Jones, O.A.H.; Green, P.G.; Voulvoulis, N.; & Lester, J.N., 2007. Questioning the Excessive Use of Advanced Treatment to Remove Organic Micropollutants From Wastewater. Envir. Sci. & Technol., 41:14:5085. Kidd, K.A.; Blanchfield, P.J.; Mills, K.H.; Palace, V.P.; Evans, R.E.; Lazorchak, J.M.; & Flick, R.W., 2007. Collapse of a Fish Population After Exposure to a

human health?’ Only then can we make intelligent, rational decisions that protect the health of this country’s municipal water customers.” CECs are an issue for both water and wastewater utilities. AWWA members and member utilities should encourage cooperation among water and wastewater organizations, such as AWWA and WEF, to provide leadership and dialog for the development of standards and mutual policies to prevent and treat CECs in the water cycle. ABOUT THE AUTHORS

Lorien J. Fono (to whom correspondence should be addressed) is an engineer with Carollo Engineers, 2700 Ygnacio Valley Rd., Ste. 300, Walnut Creek, CA 94598; [email protected]. Fono received

Synthetic Estrogen. PNAS, 104:21:8897. Kolpin, D.W., Furlong, E.T.; Meyer, M.T.; Thurman, E.M.; Zaugg, S.E.; Barber, L.B.; & Buxton, H.T., 2002. Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in US Streams, 1999–2000: A National Reconnaissance. Envir. Sci. & Technol., 36:6:1202. Nash, J.P., Kime, D.E.; Van der Ven, L.T.M.; Wester, P.W.; Brion, F.; Maack, G.; Stahlschmidt-Allner, P.; & Tyler, C.R., 2004. Long-term Exposure to Environmental Concentrations of the Pharmaceutical Ethynylestradiol Causes Reproductive Failure in Fish. Envir. Health Persp., 112:17:1725. Rosenfeldt, E.J. & Linden, K.G., 2004. Degradation of Endocrine Disrupting Chemicals Bisphenol A, Ethinyl Estradiol, and Estradiol During UV Photolysis and Advanced Oxidation Processes. Envir. Sci. & Technol., 38:20:5476. Salveson, A.T., Atapattu, K.P.; Linden, K.; Robinson, K.; Bowman, R.; ThurstonEnriquez, J.; & Cooper, R., 2007. Innovative Treatment Technologies for Reclaimed Water—Ozone/Hydrogen Peroxide Pilot Test Report at DSRSD. Proc. 22nd Annual WateReuse Symposium, Tampa, Fla.

FONO & MCDONALD

her master’s and doctorate degrees in environmental engineering from the University of California at Berkley. She was awarded the Graduate Student Research Paper Award from the American Chemical Society’s Environmental Chemistry Division and has had articles published in Environmental Chemistry and Technology and Water Environment Research. At Carollo she has worked in an advisory capacity on projects to treat emerging contaminants in drinking water and wastewater. She also has provided support for other firms that need an emerging contaminant component to their environmental impact reports. She is a member of the Water Environment Federation and has participated in drafting its literature reviews and Technical Practice Updates on emerging contaminants. H. Stephen McDonald is a partner with Carollo Engineers.

Snyder, S.A., 2007. Relative Risks of Estrogens in Reuse Water. Proc. 22nd Annual WaterReuse Symposium, Tampa, Fla.. Snyder, S.A.; Westerhoff, P.; Yeomin, Y.; Sedlak, D.L., 2003. Pharmaceuticals, Personal Care Products, and Endocrine Disruptors in Water: Implications for the Water Industry. Envir. Engrg. Sci., 20:5:449. Ternes, T.; Joss, A.; & Siegrist, H., 2007. Contaminants of Emerging Concern—A Challenge for Urban Water Management. WEF Special Symposium on Compounds of Emerging Concern, Providence, R.I. Tischler, L., et al, 2007. Potential Releases of Unused Medicines in Landfill Leachate. WEF Special Symposium for Compounds of Emerging Concern, Providence, R.I. USEPA, (US Environmental Protection Agency), 2008. Draft White Paper: Aquatic Life Criteria for Contaminants of Emerging Concern—Part I: General Challenges and Recommendations. USEPA Office of Water, Washington. Zuccato, E.; Chiabrando, C.; Castiglioni, S.; Calamari, D.; Bagnati, R.; Schiarea, S.; & Fanelli, R., 2005. Cocaine in Surface Waters: A New Evidence-Based Tool to Monitor Community Drug Abuse. Environ Health, 4:14.

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2008 © American Water Works Association

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