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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: 4098

Agricultural chemicals in Iowa's ground water, 1982-95: What are the trends? Agricultural chemicals in Iowa's ground water, 1982-95: What are the trends?

The Iowa Department of Natural Resources. Geological Survey Bureau: the University of Iowa Hygienic Laboratory; and the U.S. Geological Survey (USGS) have been working together to address this question. As part of the Iowa Ground-Water Monitoring Program (IGWM). water samples have been collected from selected Iowa municipal wells since 1982. An examination of this data identified two...
Authors
Dana W. Koplin, George Hallberg, D. A. Sneck-Fahrer, Robert Libra

Studies of the San Francisco Bay, California, estuarine ecosystem regional monitoring program results, 1996 Studies of the San Francisco Bay, California, estuarine ecosystem regional monitoring program results, 1996

As part of a regional monitoring program, water samples were collected in the San Francisco Bay estuary during 21 cruises from January through December 1996. Conductivity, temperature, light attenuation, turbidity, oxygen, and in-vivo chlorophyll fluorescence were measured longitudinally and vertically in the main channel of the estuary from south of the Dumbarton Bridge in the southern...
Authors
Jelriza I. Baylosis, Jody L. Edmunds, Brian E. Cole, James E. Cloern

Identification of ionic chloroacetanilide-herbicide metabolites in surface water and groundwater by HPLC/MS using negative ion spray Identification of ionic chloroacetanilide-herbicide metabolites in surface water and groundwater by HPLC/MS using negative ion spray

Solid-phase extraction (SPE) was combined with high-performance liquid chromatography/high-flow pneumatically assisted electrospray mass spectrometry (HPLC/ESP/MS) for the trace analysis of oxanilic and sulfonic acids of acetochlor, alachlor, and metolachlor. The isolation procedure separated the chloroacetanilide metabolites from the parent herbicides during the elution from C18...
Authors
Imma Ferrer, E.M. Thurman, Damia Barcelo

Assessing aquifer contamination risk using immunoassay: Trace analysis of atrazine in unsaturated zone sediments Assessing aquifer contamination risk using immunoassay: Trace analysis of atrazine in unsaturated zone sediments

The vulnerability of a shallow aquifer in south-central Kansas to contamination by atrazine (2-chloro-4-ethylamino-6-isopropylamines-triazine) was assessed by analyzing unsaturated zone soil and sediment samples from about 60 dryland and irrigated sites using an ultrasensitive immunoassay (detection level of 0.02 µg/kg) with verification by gas chromatography/mass spectrometry (GC/MS)...
Authors
K. E. Juracek, E.M. Thurman

Terbuthylazine and deethylterbuthylazine in rain and surface water: Determination by enzyme immunoassay and gas chromatography/mass spectrometry Terbuthylazine and deethylterbuthylazine in rain and surface water: Determination by enzyme immunoassay and gas chromatography/mass spectrometry

Rain and surface water samples from Southern Germany were investigated from 1991 to 1995 for terbuthylazine and one of its major metabolites, deethylterbuthylazine. The concentrations observed were compared to the concentrations found for atrazine and deethylatrazine in the same water samples. Concentrations ranged from 0.02 μg/L to 0.7 μg/L for terbuthylazine and from 0.02 μg/L to 0.6...
Authors
A. Dankwardt, E.M. Thurman, B. Hock

Marine bacterial degradation of brominated methanes Marine bacterial degradation of brominated methanes

Brominated methanes are ozone-depleting compounds whose natural sources include marine algae such as kelp. Brominated methane degradation by bacteria was investigated to address whether bacterial processes might effect net emission of these compounds to the atmosphere. Bacteria in seawater collected from California kelp beds degraded CH2Br2 but not CHBr3. Specific inhibitors showed that...
Authors
K.D. Goodwin, M.E. Lidstrom, R.S. Oremland

Modeling structural influences on soil water retention Modeling structural influences on soil water retention

A new model quantities the effect of soil structure, considered as the arrangement of particles in the soil, on soil water retention. The model partitions the pore space into texture-related and structure-related components, the textural component being what can be deduced to exist if the arrangement of the particles were random, and the structural component being the remainder. An...
Authors
J. R. Nimmo
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