Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
GeoHEALTH-USGS Newsletter
GeoHEALTH-USGS Newsletter
The GeoHEALTH–USGS Newsletter—published since 2004—provides information on USGS science activities pertinent to safeguarding the health of fish, wildlife, domesticated animals, and people from environmental exposures to contaminants and pathogens.
Featured Science Activities
Featured Science Activities
Learn about our Featured Science Activities through our pages that highlight studies, publications, and results.
Filter Total Items: 4097
Isolation and chemical characterization of dissolved and colloidal organic matter Isolation and chemical characterization of dissolved and colloidal organic matter
Commonly used techniques for the concentration and isolation of organic matter from water, such as preparative chromatography, ultrafiltration and reverse osmosis, and the methods used to analyze the organic matter obtained by these methods are reviewed. The development of methods to obtain organic matter that is associated with fractions of the dissolved organic carbon other than humic...
Authors
G. Aiken, J. Leenheer
Spatial variability of triazine herbicides in the Lower Mississippi River Spatial variability of triazine herbicides in the Lower Mississippi River
No abstract available.
Authors
J. A. Moody, D. A. Goolsby
Assessing the effect of pesticides in agricultural runoff on aquatic life in the Sangamon River near Monticello, Illinois Assessing the effect of pesticides in agricultural runoff on aquatic life in the Sangamon River near Monticello, Illinois
Stream-water samples collected from a midwest stream, following a thunderstorm during May 1991 were toxic to water fleas (Ceriodaphnia dubia), but not fathead minnows (Pimephales promelas), or a bacterium (Photobacterium phosphoreum) or green alga (Selenastrum capricornutum). It was unlikely that the toxicity to the water fleas was caused by herbicides, but it may have been caused by...
Authors
R.H. Coupe, M.S. Henebry, M.R. Branham
Analysis of flow in an observation well intersecting a single fracture Analysis of flow in an observation well intersecting a single fracture
A semi-analytical model is developed to determine transmissivity and storativity from the interpretation of transient flow in an observation well due to pumping in a source well where the two wells are connected by a single fracture. Flow rate can be determined using a heat-pulse flowmeter located above the intersection of the fracture in the observation well. The results of a field...
Authors
P.A. Lapcevic, K.S. Novakowski, Frederick L. Paillet
Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California
Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objectives were to determine the concentrations of these contaminants in water and...
Authors
Joseph L. Domagalski, K.M. Kuivila
New reference materials for nitrogen-isotope-ratio measurements New reference materials for nitrogen-isotope-ratio measurements
Three new reference materials were manufactured for calibration of relative stable nitrogen‐isotope‐ratio measurements: USGS25 (ammonium sulfate) δ615″=−30 per mil USGS26 (ammonium sulfate) δ615″=+54 per mil USGS32 (potassium nitrate) δ615″=+180 per mil where δN′, relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These...
Authors
J.K. Bohlke, C. J. Gwinn, T. B. Coplen
Effects of small-scale vertical variations in well-screen inflow rates and concentrations of organic compounds on the collection of representative ground-water-quality samples Effects of small-scale vertical variations in well-screen inflow rates and concentrations of organic compounds on the collection of representative ground-water-quality samples
Because a water sample collected from a well is an integration of water from different depths along the well screen, measured concentrations can be biased if analyte concentrations are not uniform along the length of the well screen. The resulting concentration in the sample, therefore, is a function of variations in well-screen inflow rate and analyte concentration with depth. A...
Authors
Jacob Gibs, G. Allan Brown, Kenneth S. Turner, Cecilia L. MacLeod, James Jelinski, Susan A. Koehnlein
Tracer-dilution experiments and solute-transport simulations for a mountain stream, Saint Kevin Gulch, Colorado Tracer-dilution experiments and solute-transport simulations for a mountain stream, Saint Kevin Gulch, Colorado
No abstract available.
Authors
R. E. Broshears, K.E. Bencala, B. A. Kimball, Diane M. McKnight
Data on chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula Data on chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula
No abstract available.
Authors
Niel Plummer, S.A. Dunkle, Eurybiades Busenberg
Documentation of a computer program to simulate horizontal-flow barriers using the U.S. Geological Survey's modular three-dimensional finite-difference ground-water flow model Documentation of a computer program to simulate horizontal-flow barriers using the U.S. Geological Survey's modular three-dimensional finite-difference ground-water flow model
No abstract available.
Authors
Paul A. Hsieh, John R. Freckleton
Patterns of hydrological exchange and nutrient transformation in the hyporheic zone of a gravel-bottom stream: examining terrestrial- aquatic linkages Patterns of hydrological exchange and nutrient transformation in the hyporheic zone of a gravel-bottom stream: examining terrestrial- aquatic linkages
The terrestrial-aquatic interface beneath a riparian corridor was investigated as a region of hydrological and biological control of nutrient flux. Dissolved oxygen (DO) concentration in the hyporheic zone ranged from
Authors
F.J. Triska, J.H. Duff, R.J. Avanzino
Effects of focused recharge on the transport of agricultural chemicals at the Princeton, Minnesota Management Systems Evaluation Area, 1991-92 Effects of focused recharge on the transport of agricultural chemicals at the Princeton, Minnesota Management Systems Evaluation Area, 1991-92
Rates of water movement through the unsaturated zone greatly affect the amount and concentrations of agricultural chemicals that may reach the water table. For example, recharge can flush chemicals to the water table which have accumulated in the unsaturated zone during dry periods. A better understanding of how topography influences recharge and the movement of agricultural chemicals is...
Authors
G. N. Delin, M.K. Landon