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Dive into the research topics where James L. Gray is active.

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Featured researches published by James L. Gray.


Environmental Toxicology and Chemistry | 2003

Quantification of Steroid Hormones With Pheromonal Properties in Municipal Wastewater Effluent

Edward P. Kolodziej; James L. Gray; David L. Sedlak

Many fish use steroid hormones as pheromones to initiate behavioral and physiological changes during spawning. To assess the occurrence of steroid hormones with pheromonal properties in the aquatic environment and to evaluate the possibility that municipal wastewater discharges contain compounds that could affect fish reproduction by interfering with pheromones, several estrogens, androgens, and progestins were quantified by gas chromatography/tandem mass spectroscopy in effluent samples from 12 municipal wastewater treatment plants. Samples also were analyzed from an engineered treatment wetland, three groundwater wells, and one reservoir. Estrogens (17beta-estradiol and estrone) were detected in wastewater effluent at maximum concentrations of 4 and 12 ng/L, respectively. Androgens (testosterone and androstenedione) were detected at concentrations as high as 6.1 and 4.5 ng/L, respectively, whereas the synthetic progestin medroxyprogesterone was detected at concentrations up to 15 ng/L. Data from an effluent-receiving engineered treatment wetland and shallow groundwater wells suggested that these compounds were not rapidly attenuated. The measured concentrations of steroids often exceeded olfactory detection thresholds at which fish detect these steroids, and in several cases, the steroid concentrations were comparable to levels at which pheromonal responses have been observed in fish.


Environmental Science & Technology | 2012

Combined sewer overflows: an environmental source of hormones and wastewater micropollutants.

Patrick J. Phillips; A. T. Chalmers; James L. Gray; Dana W. Kolpin; William T. Foreman; G. R. Wall

Data were collected at a wastewater treatment plant (WWTP) in Burlington, Vermont, USA, (serving 30,000 people) to assess the relative contribution of CSO (combined sewer overflow) bypass flows and treated wastewater effluent to the load of steroid hormones and other wastewater micropollutants (WMPs) from a WWTP to a lake. Flow-weighted composite samples were collected over a 13 month period at this WWTP from CSO bypass flows or plant influent flows (n = 28) and treated effluent discharges (n = 22). Although CSO discharges represent 10% of the total annual water discharge (CSO plus treated plant effluent discharges) from the WWTP, CSO discharges contribute 40–90% of the annual load for hormones and WMPs with high (>90%) wastewater treatment removal efficiency. By contrast, compounds with low removal efficiencies (<90%) have less than 10% of annual load contributed by CSO discharges. Concentrations of estrogens, androgens, and WMPs generally are 10 times higher in CSO discharges compared to treated wastewater discharges. Compound concentrations in samples of CSO discharges generally decrease with increasing flow because of wastewater dilution by rainfall runoff. By contrast, concentrations of hormones and many WMPs in samples from treated discharges can increase with increasing flow due to decreasing removal efficiency.


Environmental Science & Technology | 2000

Peer reviewed: understanding microcontaminants in recycled water.

David L. Sedlak; James L. Gray; Karen E. Pinkston

Increasing attention is being given to the detection, treatment, and removal of problematic effluent-derived contaminants.


Environmental Science & Technology | 2013

Persistence and potential effects of complex organic contaminant mixtures in wastewater-impacted streams

Larry B. Barber; Steffanie H. Keefe; Greg Brown; Edward T. Furlong; James L. Gray; Dana W. Kolpin; Michael T. Meyer; Mark W. Sandstrom; Steven D. Zaugg

Natural and synthetic organic contaminants in municipal wastewater treatment plant (WWTP) effluents can cause ecosystem impacts, raising concerns about their persistence in receiving streams. In this study, Lagrangian sampling, in which the same approximate parcel of water is tracked as it moves downstream, was conducted at Boulder Creek, Colorado and Fourmile Creek, Iowa to determine in-stream transport and attenuation of organic contaminants discharged from two secondary WWTPs. Similar stream reaches were evaluated, and samples were collected at multiple sites during summer and spring hydrologic conditions. Travel times to the most downstream (7.4 km) site in Boulder Creek were 6.2 h during the summer and 9.3 h during the spring, and to the Fourmile Creek 8.4 km downstream site times were 18 and 8.8 h, respectively. Discharge was measured at each site, and integrated composite samples were collected and analyzed for >200 organic contaminants including metal complexing agents, nonionic surfactant degradates, personal care products, pharmaceuticals, steroidal hormones, and pesticides. The highest concentration (>100 μg L(-1)) compounds detected in both WWTP effluents were ethylenediaminetetraacetic acid and 4-nonylphenolethoxycarboxylate oligomers, both of which persisted for at least 7 km downstream from the WWTPs. Concentrations of pharmaceuticals were lower (<1 μg L(-1)), and several compounds, including carbamazepine and sulfamethoxazole, were detected throughout the study reaches. After accounting for in-stream dilution, a complex mixture of contaminants showed little attenuation and was persistent in the receiving streams at concentrations with potential ecosystem implications.


Environmental Science & Technology | 2010

Evaluating the Behavior of Gadolinium and Other Rare Earth Elements through Large Metropolitan Sewage Treatment Plants

Philip L. Verplanck; Edward T. Furlong; James L. Gray; Patrick J. Phillips; Ruth E. Wolf; Kathleen Esposito

A primary pathway for emerging contaminants (pharmaceuticals, personal care products, steroids, and hormones) to enter aquatic ecosystems is effluent from sewage treatment plants (STP), and identifying technologies to minimize the amount of these contaminants released is important. Quantifying the flux of these contaminants through STPs is difficult. This study evaluates the behavior of gadolinium, a rare earth element (REE) utilized as a contrasting agent in magnetic resonance imaging (MRI), through four full-scale metropolitan STPs that utilize several biosolids thickening, conditioning, stabilization, and dewatering processing technologies. The organically complexed Gd from MRIs has been shown to be stable in aquatic systems and has the potential to be utilized as a conservative tracer in STP operations to compare to an emerging contaminant of interest. Influent and effluent waters display large enrichments in Gd compared to other REEs. In contrast, most sludge samples from the STPs do not display Gd enrichments, including primary sludges and end-product sludges. The excess Gd appears to remain in the liquid phase throughout the STP operations, but detailed quantification of the input Gd load and residence times of various STP operations is needed to utilize Gd as a conservative tracer.


Water Environment Research | 2005

The fate of estrogenic hormones in an engineered treatment wetland with dense macrophytes

James L. Gray; David L. Sedlak

Recently, the estrogenic hormones 17beta-estradiol (E2) and 17alpha-ethinyl estradiol (EE2) have been detected in municipal wastewater effluent and surface waters at concentrations sufficient to cause feminization of male fish. To evaluate the fate of steroid hormones in an engineered treatment wetland, lithium chloride, E2, and EE2 were added to a treatment wetland test cell. Comparison of hormone and tracer data indicated that 36% of the E2 and 41% of the EE2 were removed during the cells 84-h hydraulic retention time (HRT). The observed attenuation was most likely the result of sorption to hydrophobic surfaces in the wetland coupled with biotransformation. Sorption was indicated by the retardation of the hormones relative to the conservative tracer. Biotransformation was indicated by elevated concentrations of the E2 metabolite, estrone. It may be possible to improve the removal efficiency by increasing the HRT or the density of plant materials.


Techniques and Methods | 2012

Determination of steroid hormones and related compounds in filtered and unfiltered water by solid-phase extraction, derivatization, and gas chromatography with tandem mass spectrometry

William T. Foreman; James L. Gray; Rhiannon C. ReVello; Chris E. Lindley; Scott A. Losche; Larry B. Barber

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Environmental Science & Technology | 2010

A role for analytical chemistry in advancing our understanding of the occurrence, fate, and effects of Corexit oil dispersants.

Ben Place; Brian S. Anderson; Abdou Mekebri; Edward T. Furlong; James L. Gray; Ronald S. Tjeerdema; Jennifer A. Field

On April 24, 2010, the sinking of the Deepwater Horizon oil rig resulted in the release of oil into the Gulf of Mexico. As of July 19, 2010, the federal government’s Deepwater Horizon Incident Joint Information Center estimates the cumulative range of oil released is 3,067,000 to 5,258,000 barrels, with a relief well to be completed in early August. By comparison, the Exxon Valdez oil spill released a total of 260,000 barrels of crude oil into the environment. As of June 9, BP has used over 1 million gallons of Corexit oil dispersants to solubilize oil and help prevent the development of a surface oil slick (1). Oil dispersants are mixtures containing solvents and surfactants that can exhibit toxicity toward aquatic life and may enhance the toxicity of components of weathered crude oil. Detailed knowledge of the composition of both Corexit formulations and other dispersants applied in the Gulf will facilitate comprehensive monitoring programs for determining the occurrence, fate, and biological effects of the dispersant chemicals. The lack of information on the potential impacts of oil dispersants has caught industry, federal, and state officials off guard. Until compositions of Corexit 9500 and 9527 were released by the U.S. Environmental Protection Agency online, the only information available consisted of Material Safety Data Sheets (MSDS), patent documentation, and a National Research Council report on oil dispersants (2). Several trade and common names are used for the components of the Corexits. For example, Tween 80 and Tween 85 are oligomeric mixtures.


Environmental Toxicology and Chemistry | 2016

Landfill leachate as a mirror of today's disposable society: Pharmaceuticals and other contaminants of emerging concern in final leachate from landfills in the conterminous United States

Jason R. Masoner; Dana W. Kolpin; Edward T. Furlong; Isabelle M. Cozzarelli; James L. Gray

Final leachates (leachate after storage or treatment processes) from 22 landfills in 12 states were analyzed for 190 pharmaceuticals and other contaminants of emerging concern (CECs), which were detected in every sample, with the number of CECs ranging from 1 to 58 (median = 22). In total, 101 different CECs were detected in leachate samples, including 43 prescription pharmaceuticals, 22 industrial chemicals, 15 household chemicals, 12 nonprescription pharmaceuticals, 5 steroid hormones, and 4 animal/plant sterols. The most frequently detected CECs were lidocaine (91%, local anesthetic), cotinine (86%, nicotine degradate), carisoprodol (82%, muscle relaxant), bisphenol A (77%, component of plastics and thermal paper), carbamazepine (77%, anticonvulsant), and N,N-diethyltoluamide (68%, insect repellent). Concentrations of CECs spanned 7 orders of magnitude, ranging from 2.0 ng/L (estrone) to 17,200,000 ng/L (bisphenol A). Concentrations of household and industrial chemicals were the greatest (∼1000-1,000,000 ng/L), followed by plant/animal sterols (∼1000-100,000 ng/L), nonprescription pharmaceuticals (∼100-10,000 ng/L), prescription pharmaceuticals (∼10-10,000 ng/L), and steroid hormones (∼10-100 ng/L). The CEC concentrations in leachate from active landfills were significantly greater than those in leachate from closed, unlined landfills (p = 0.05). The CEC concentrations were significantly greater (p < 0.01) in untreated leachate compared with treated leachate. The CEC concentrations were significantly greater in leachate disposed to wastewater treatment plants from modern lined landfills than in leachate released to groundwater from closed, unlined landfills (p = 0.04). The CEC concentrations were significantly greater (p = 0.06) in the fresh leachate (leachate before storage or treatment) reported in a previous study compared with the final leachate sampled for the present study.


Chimia | 2003

Approaches for Quantifying the Attenuation of Wastewater-Derived Contaminants in the Aquatic Environment

David L. Sedlak; Karen E. Pinkston; James L. Gray; Edward P. Kolodziej

The effluent from municipal wastewater treatment plants contains trace concentrations of a variety of organic compounds. To assess the removal of these compounds in full-scale treatment systems and effluent-receiving waters, approaches are needed for quantifying removal rates and mechanisms. For processes that result in near complete removal of wastewater-derived contaminants, it is reasonable to measure concentrations entering and leaving the treatment system. However, for those compounds that are not completely removed, alternative methods are needed. This paper describes several examples of approaches that combine laboratory and field studies to assess the attenuation of wastewater-derived contaminants.

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Edward T. Furlong

United States Geological Survey

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Dana W. Kolpin

United States Geological Survey

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Larry B. Barber

United States Geological Survey

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William T. Foreman

United States Geological Survey

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Patrick J. Phillips

United States Geological Survey

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Rhiannon C. ReVello

United States Geological Survey

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Steffanie H. Keefe

United States Geological Survey

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Steven D. Zaugg

United States Geological Survey

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