Geology topics
E.A. Scribner
Publications and source records attributed to E.A. Scribner.
Occurrence of antibiotics in water from 13 fish hatcheries, 2001-2003
A 2-year study of extensive and intensive fish hatcheries was conducted to assess the general temporal occurrence of antibiotics in aquaculture. Antibiotics were detected in 15% of the water samples collected during the 2001-2002 collection period and in 31% of the samples during the 2003 collection period. Antibiotics were detected more frequently in samples from the intensive hatcheries (17 and 39%) than in samples from the extensive hatcheries (14 and 4%) during the 2001-2002 and 2003 collection periods, respectively. The maximum ormetoprim, oxytetracycline, and sulphadimethoxine concentrations were higher in samples from the intensive hatcheries (12, 10, and 36 µg L-1), respectively, than in samples from the extensive hatcheries (<0.05, 0.31, and 1.2 µg L-1), respectively. Sulphadimethoxine persisted for a longer period of time (up to 48 days) than ormetoprim (up to 28 days) and oxytetracycline (less than 20 days).
Herbicides and degradates in shallow aquifers of Illinois: Spatial and temporal trends
During the fall of 2000, the occurrence was examined of 16 herbicides and 13 herbicide degradates in samples from 55 wells in shallow aquifers underlying grain producing regions of Illinois. Herbicide compounds with concentrations above 0.05 μg/L were detected in 56 percent of the samples. No concentrations exceeded regulatory drinking water standards. The six most frequently detected compounds were degradates. Water age was an important factor in determining vulnerability of ground water to transport of herbicide compounds. Unconsolidated aquifers, which were indicated to generally contain younger ground water than bedrock aquifers, had a higher occurrence of herbicides (73 percent of samples) than bedrock aquifers (22 percent). Temporal analysis to determine if changes in concentrations of selected herbicides and degradates could be observed over a near decadal period indicated a decrease in detection frequency (25 to 18 percent) between samplings in 1991 and 2000. Over this period, significant differences in concentrations were observed for atrazine (decrease) and total acetochlor (increase). The increase in acetochlor compound concentrations corresponds to an increase in acetochlor use during the study period, while the decrease in atrazine concentrations corresponds to relatively consistent use of atrazine. Changes in frequency of herbicide detection and concentration do not appear related to changes in land use near sampled wells.
Work plan for determining the occurrence of glyphosate, its transformation product AMPA, other herbicide compounds, and antibiotics in midwestern United States streams, 2002
Changes in herbicide use in the Midwestern United States have been substantial over the last 5 years. Most significant is a tripling in the use of glyphosate (N-[phosphonomethyl]glycin). Over this same time period (1997­2001), atrazine use increased by 20 percent and acetochlor use increased by 10 percent, while cyanazine use decreased by 99 percent, alachlor use decreased by 70 percent, and metolachlor use decreased by 55 percent. Previous studies have documented that herbicide flushes occur in midwestern streams during runoff events for several weeks to several months following application, and that herbicide concentrations in midwestern streams during flushing events are related to rates of herbicide use. The objective of this study is to determine the distribution of glyphosate and its primary transformation product aminomethylphosphonic acid (AMPA) in midwestern streams during post-application and harvest-season runoff events. Water samples will be collected in 2002 during two post-herbicide-application runoff events and one harvest-season runoff event from 53 sites on streams in the Midwestern United States. All samples will be analyzed at the U.S. Geological Survey Organic Geochemistry Research Laboratory in Lawrence, Kansas, for glyphosate and 20 other herbicides. Samples will also be analyzed for a glyphosate transformation product (AMPA) and 26 other herbicide transformation products, using GC/MS or HPLC/MS. Selected samples will be analyzed for 36 antibiotics or antibiotic transformational products. Results from this study will represent the first broad-scale investigation of glyphosate and AMPA in U.S. water resources.
Analysis of selected herbicide metabolites in surface and ground water of the United States
One of the primary goals of the US Geological Survey (USGS) Laboratory in Lawrence, Kansas, is to develop analytical methods for the analysis of herbicide metabolites in surface and ground water that are vital to the study of herbicide fate and degradation pathways in the environment. Methods to measure metabolite concentrations from three major classes of herbicides — triazine, chloroacetanilide and phenyl-urea — have been developed. Methods for triazine metabolite detection cover nine compounds: six compounds are detected by gas chromatography/mass spectrometry; one is detected by high-performance liquid chromatography with diode-array detection; and eight are detected by liquid chromatography/mass spectrometry. Two metabolites of the chloroacetanilide herbicides — ethane sulfonic acid and oxanilic acid — are detected by high-performance liquid chromatography with diode-array detection and liquid chromatography/mass spectrometry. Alachlor ethane sulfonic acid also has been detected by solid-phase extraction and enzyme-linked immunosorbent assay. Six phenylurea metabolites are all detected by liquid chromatography/mass spectrometry; four of the six metabolites also are detected by gas chromatography/mass spectrometry. Additionally, surveys of herbicides and their metabolites in surface water, ground water, lakes, reservoirs, and rainfall have been conducted through the USGS laboratory in Lawrence. These surveys have been useful in determining herbicide and metabolite occurrence and temporal distribution and have shown that metabolites may be useful in evaluation of non-point-source contamination.
Changes in herbicide concentrations in Midwestern streams in relation to changes in use, 1989-1998
Water samples were collected from Midwestern streams in 1994–1995 and 1998 as part of a study to help determine if changes in herbicide use resulted in changes in herbicide concentrations since a previous reconnaissance study in 1989–1990. Sites were sampled during the first significant runoff period after the application of pre-emergent herbicides in 1989–1990, 1994–1995, and 1998. Samples were analyzed for selected herbicides, two atrazine metabolites, three cyanazine metabolites, and one alachlor metabolite. In the Midwestern USA, alachlor use was much greater in 1989 than in 1995, whereas acetochlor was not used in 1989 but was commonly used in 1995. The use of atrazine, cyanazine, and metolachlor was approximately the same in 1989 and 1995. The median concentrations of atrazine, alachlor, cyanazine, and metolachlor were substantially higher in 1989–1990 than in 1994–1995 or 1998. The median acetochlor concentration was higher in 1998 than in 1994 or 1995.
Methods of analysis by the U.S. Geological Survey Organic Geochemistry Research Group: Determination of selected herbicides and their degradation products in water using solid-phase extraction and gas chromatography/mass spectrometry
A method for the extraction and analysis of eight herbicides and five degradation products using solid-phase extraction from natural water samples followed by gas chromatography/mass spectrometry is presented in this report. This method was developed for dimethenamid; flufenacet; fluometuron and its degradation products, demethylfluometuron (DMFM), 3-(trifluromethyl) phenylurea (TFMPU), 3-(trifluromethyl)-aniline (TFMA); molinate; norflurazon and its degradation product, demethylnorflurazon; pendamethalin; the degradation product of prometryn, deisopropylprometryn; propanil; and trifluralin. The eight herbicides are used primarily in the southern United States where cotton, rice, and soybeans are produced. The exceptions are dimethenamid and flufenacet, which are used on corn in the Midwest. Water samples received by the U.S. Geological Survey's Organic Geochemistry Research Group in Lawrence, Kansas, are filtered to remove suspended particulate matter and then passed through disposable solid-phase extraction columns containing octadecyl-bonded porous silica (C-18) to extract the compounds. The herbicides and their degradation products are removed from the column by ethyl acetate elution. The eluate is evaporated under nitrogen, and components then are separated, identified, and quantified by injecting an aliquot of the concentrated extract into a high-resolution, fused-silica capillary column of a gas chromatograph/mass spectrometer under selected-ion mode. Method detection limits ranged from 0.02 to 0.05 μg/L for all compounds with the exception of TFMPU, which has a method detection limit of 0.32 μg/L. The mean absolute recovery is 107 percent. This method for the determination of herbicides and their degradation products is valuable for acquiring information about water quality and compound fate and transport in water.
A reconnaissance for selected herbicides, metabolites, and nutrients in streams of nine Midwestern States, 1994-95
No abstract available.
Concentrations of selected herbicides, herbicide metabolites, and nutrients in outflow from selected midwestern reservoirs, April 1992 through September 1993
This data set consists of digital aquifer boundaries for the High Plains aquifer in the central United States. The High Plains aquifer extends from south of 32 degrees to almost 45 degrees north latitude and from 96 degrees 30 minutes to almost 104 degrees west longitude. The area covers 174,000 square miles and is present in Texas, Oklahoma, New Mexico, Kansas, Colorado, Nebraska, Wyoming, and South Dakota. This digital data set was created by digitizing the aquifer boundaries from a 1:1,000,000 base map created by the High Plains RASA project (Gutentag and others, 1984).
Data on selected herbicides and two triazine metabolites in precipitation of the Midwestern and Northeastern United States, 1990-91
Weekly precipitation (rain and snow) samples were collected from 81 National Atmospheric Deposition Program/National Trends Network sites in the Midwestern and Northeastern United States for the analysis of herbicides. In addition, five high- elevation background sites along the Rocky Mountains and in Alaska were sampled to provide data on herbicides in precipitation at sites far from the study area. The study began in March 1990 and continued through September 1991. The precipitation samples were shipped to the Central Analytical Laboratory operated by the Illinois State Water Survey for analyses of inorganic compounds. Subsamples of the precipitation were shipped to the U.S. Geological Survey laboratory in Lawrence, Kansas, for the analysis of 11 herbicides and 2 triazines metabolites. This report provides descriptions of the study area, sample-collection methods, laboratory methods, and quality assurance. The report also includes a compilation of herbicide concentration data from both enzyme-linked immunosorbent assay and gas chromatography/mass spectrometry methods. Laboratory analyses consisted of 6,230 samples that were analyzed by enzyme-linked immunosorbent assay using alachlor and atrazine microtiter plates and 2,341 samples that were confirmed by gas chromatography/mass spectrometry analysis. Graphical and statistical comparisons of the two analytical methods are given in this report. Data from this study have been useful in determining the spatial and temporal distribution of herbicide concentrations and deposition in precipitation of over a 26-State area of the Midwestern and Northeastern United States. The data also provide evidence of long-range atmospheric transport of herbicides and triazine metabolites.
Reconnaissance data for selected herbicides, two atrazine metabolities, and nitrate in surface water of the Midwestern United States, 1989-90
Water-quality data were collected from 147 rivers and streams during 1989-90 to assess selected preemergent herbicides, two atrazine metabolites, and nitrate in 10 Midwestern States. This report includes a description of the sampling design, data collection techniques, laboratory and analytical methods, and a compilation of constituent concentrations and quality-assurance data. All water samples were collected by depth-integrating techniques at three to five locations across the wetted perimeter of each stream. Sites were sampled three times in l989--before application of herbi- cides, during the first major runoff after appli- cation of herbicides, and in the fall during a low-flow period when ground water contributed to most of the streamflow. About 50 sites were selected by a stratified random procedure and resampled for both pre- and post-application herbicide concen- trations in 1990 to verify the 1989 results. Laboratory analyses consisted of both enzyme-linked immunosorbent assay (ELISA) with confirmation by gas chromatography-mass spectrometry (GC/MS). The data are useful in studying herbicide transport, in comparison of the spatial distribution of the post-application concentrations of 11 herbicides and 2 atrazine metabolites (deethylatrazine and deisopropylatrazine) in streams and rivers at a regional scale. It is also useful in examination of annual persistence of herbicides and two metabolites in surface water, and in the assessment of atrazine metabolites as indicators of surface- and ground- water interaction. The reconnaissance data are contained in this report and are also available on computer diskette from the U.S. Geological Survey in Lawrence, Kansas.