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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 3746

Pathogenic bacteria and microbial-source tracking markers in Brandywine Creek Basin, Pennsylvania and Delaware, 2009-10

The City of Wilmington, Delaware, is in the downstream part of the Brandywine Creek Basin, on the main stem of Brandywine Creek. Wilmington uses this stream, which drains a mixed-land-use area upstream, for its main drinking-water supply. Because the stream is used for drinking water, Wilmington is in need of information about the occurrence and distribution of specific fecally derived pathogenic
Authors
Joseph W. Duris, Andrew G. Reif, Leif E. Olson, Heather E. Johnson

Editor’s message: Groundwater modeling fantasies - Part 2, down to earth

Simplicity is the final achievement. After one has played a vast quantity of notes and more notes, it is simplicity that emerges as the crowning reward of art. (Frédéric Chopin, a musician and composer, quoted in If Not God, Then What? by Fost 2007)Despite the dubious developments discussed in part 1 of this Editor’s Message (Voss 2011), groundwater modeling really does represent the state of the
Authors
Clifford I. Voss

Quality of our groundwater resources: Arsenic and fluoride

Groundwater often contains arsenic or fluoride concentrations too high for drinking or cooking. These constituents, often naturally occurring, are not easy to remove. The right combination of natural or manmade conditions can lead to elevated arsenic or fluoride which includes continental source rocks, high alkalinity and pH, reducing conditions for arsenic, high phosphate, high temperature and hi
Authors
D. Kirk Nordstrom

Editor’s message: Groundwater modeling fantasies - Part 1, adrift in the details

Fools ignore complexity. Pragmatists suffer it. Some can avoid it. Geniuses remove it. …Simplicity does not precede complexity, but follows it. (Epigrams in Programming by Alan Perlis, a computer scientist; Perlis 1982).A doctoral student creating a groundwater model of a regional aquifer put individual circular regions around data points where he had hydraulic head measurements, so that each regi
Authors
Clifford I. Voss

Role of biofilms in sorptive removal of steroidal hormones and 4-nonylphenol compounds from streams

Stream biofilms play an important role in geochemical processing of organic matter and nutrients, however, the significance of this matrix in sorbing trace organic contaminants is less understood. This study focused on the role of stream biofilms in sorbing steroidal hormones and 4-nonylphenol compounds from surface waters using biofilms colonized in situ on artificial substrata and subsequently t
Authors
Jeffrey H. Writer, Joseph N. Ryan, Larry B. Barber

Characterization of the intragranular water regime within subsurface sediments: pore volume, surface area, and mass transfer limitations

Although "intragranular" pore space within grain aggregates, grain fractures, and mineral surface coatings may contain a relatively small fraction of the total porosity within a porous medium, it often contains a significant fraction of the reactive surface area, and can thus strongly affect the transport of sorbing solutes. In this work, we demonstrate a batch experiment procedure using tritiated
Authors
Michael B. Hay, Deborah L. Stoliker, James A. Davis, John M. Zachara

Inversion of multi-frequency electromagnetic induction data for 3D characterization of hydraulic conductivity

Electromagnetic induction (EMI) instruments provide rapid, noninvasive, and spatially dense data for characterization of soil and groundwater properties. Data from multi-frequency EMI tools can be inverted to provide quantitative electrical conductivity estimates as a function of depth. In this study, multi-frequency EMI data collected across an abandoned uranium mill site near Naturita, Colorado,
Authors
Troy R. Brosten, Frederick D. Day-Lewis, Gregory M. Schultz, Gary P. Curtis, John W. Lane

Assessing field-scale biogeophysical signatures of bioremediation over a mature crude oil spill

We conducted electrical geophysical measurements at the National Crude Oil Spill Fate and Natural Attenuation Research Site (Bemidji, MN). Borehole and surface self-potential measurements do not show evidence for the existence of a biogeobattery mechanism in response to the redox gradient resulting from biodegradation of oil. The relatively small self potentials recorded are instead consistent wit
Authors
Lee Slater, Dimitrios Ntarlagiannis, Estella Atekwana, Farag Mewafy, Andre Revil, Magnus Skold, Yuri Gorby, Frederick D. Day-Lewis, John W. Lane, Jared J. Trost, Dale D. Werkema, Geoffrey N. Delin, William N. Herkelrath

Agricultural sources of contaminants of emerging concern and adverse health effects on freshwater fish

Agricultural contaminants of emerging concern (CECs) are generally thought of as certain classes of chemicals associated with animal feeding and production facilities. Veterinary pharmaceuticals used in animal food production systems represent one of the largest groups of CECs. In our review, we discuss the extensive increase in use of antibiotics in animal feeding operations (AFOs) around the wor
Authors
Donald E. Tillitt, Herbert T. Buxton

An overview of estrogen-associated endocrine disruption in fishes: Evidence of effects on reproductive and immune physiology

Simply and perhaps intuitively defined, endocrine disruption is the abnormal modulation of normal hormonal physiology by exogenous chemicals. In fish, endocrine disruption of the reproductive system has been observed worldwide in numerous species and is known to affect both males and females. Observations of biologically relevant endocrine disruption most commonly occurs near waste water treatment
Authors
Luke R. Iwanowicz, Vicki S. Blazer

Preface: Insights from environmental tracers in groundwater systems

No abstract available.
Authors
Ward E. Sanford, Werner Aeschbach-Hertig, Andrew L. Herczeg

Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results

To minimize confusion in the expression of measurement results of stable isotope and gas-ratio measurements, recommendations based on publications of the Commission on Isotopic Abundances and Atomic Weights of the International Union of Pure and Applied Chemistry (IUPAC) are presented. Whenever feasible, entries are consistent with the Système International d'Unités, the SI (known in English as th
Authors
Tyler B. Coplen