Geology topics

Steven D. Zaugg

Publications and source records attributed to Steven D. Zaugg.

43 records · Page 3Linked to original sources

USGS2002

Response to comment on "Pharmaceuticals, hormones, and other organic wastewater contaminants in U.S. streams, 1999-2000: A national reconnaissance"

We concur with the response of Eckel to our recent publication in this Journal (1). As the author notes, the topic of emerging contaminants is currently receiving extensive media coverage and scientific notice, but there are earlier reports that foreshadow this current interest. Eckel’s comment regarding the detection of pharmaceuticals and other organic wastewater contaminants (OWC) at a Superfund landfill site (2) is well taken, as other reports confirm the presence of such compounds at waste-disposal and landfill sites (3). In fact, literature from more than 20 years ago documented the occurrence of OWCs in the environment (4-7). A significant difference between these reports and our study is that we have systematically documented the frequent presence and low concentrations of a broad suite of OWCs in a wide variety of streams across the United States.

Environmental Science & Technology↗

USGS2002

Response to comment on "Pharmaceuticals, hormones, and other organic wastewater contaminants in U.S. streams, 1999-2000: A national reconnaissance"

We thank Ericson et al. (1) for their careful review and thoughtful comments on the synthetic hormone data presented in our recent publication summarizing the results from the USGS nationwide reconnaissance for pharmaceuticals and other organic wastewater contaminants (2). Their efforts have helped raise the awareness of the difficulties in accurately measuring these compounds at the low concentrations that occur in the environment and reinforce the need for continued research in the area of analytical methods development for synthetic hormones

Environmental Science & Technology↗

USGS2002

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory-A method supplement for the determination of Fipronil and degradates in water by gas chromatography/mass spectrometry

A method for the isolation and detemrination of fipronil and four of its degradates has been developed. This method adapts an analytical method created by the U.S. Geological Survey National Water Quality Laboratory in 1995 for the determination of a broad range of high-use pesticides typically found in filtered natural-water samples. In 2000, fipronil and four of its degradates were extracted, analyzed, and validated using this method. The recoveries for these five compounds in reagent-water samples fortified at 1 microgram per liter (ug/L) avereraged 98 percent. Initial method detection limits averaged 0.0029 ug/L. The performance of these five new compounds is consistent with the performance of the compounds in the initial method, making it possible to include them in addition to the other 41 pesticides and pesticide degradates in the original method.

Open-File Report↗

USGS2002

Water-quality data for pharmaceuticals, hormones, and other organic wastewater contaminants in U.S. streams, 1999-2000

Water-quality data collected during 1999 and 2000 as part of the first nationwide reconnaissance of the occurrence of pharmaceuticals, hormones, and other organic wastewater contaminants (OWCs) are presented in this report. A network of 139 streams in 30 states were sampled and analyzed for 95 different OWCs using five new research methods developed by the U.S. Geological Survey. Site selection was biased toward streams more susceptible to OWC contamination because of proximity to urban areas or livestock production. At least one OWC was detected in 80% of the streams sampled, with 82 of the 95 analyzed OWCs determined in this study detected in at least one sample.

Open-File Report↗

USGS2002

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of wastewater compounds by polystyrene-divinylbenzene solid-phase extraction and capillary-column gas chromatography/mass spectrometry

A method for the determination of 67 compounds typically found in domestic and industrial wastewater is described. The method was developed in response to increasing concern over the impact of endocrine-disrupting chemicals in wastewater on aquatic organisms. This method also may be useful for evaluating the impact of combined sanitary and storm-sewer overflow on the water quality of urban streams. The method focuses on the determination of compounds that are an indicator of wastewater or that have been chosen on the basis of their endocrine-disrupting potential or toxicity. These compounds include the alkylphenol ethoxylate nonionic surfactants and their degradates, food additives, fragrances, antioxidants, flame retardants, plasticizers, industrial solvents, disinfectants, fecal sterols, polycyclicaromatic hydrocarbons, and high-use domestic pesticides. Water samples are filtered to remove suspended particulate matter and then are extracted by vacuum through disposable solid-phase cartridges that contain polystyrene-divinylbenzene resin. Cartridges are dried with nitrogen gas, and then sorbed compounds are eluted with dichloromethane-diethyl ether (4:1) and determined by capillary-column gas chromatography/mass spectrometry. Recoveries in reagent-water samples fortified at 4 micrograms per liter averaged 74 percent ? 7 percent relative standard deviation for all method compounds. Initial method detection limits for single-component compounds (excluding hormones and sterols) averaged 0.15 microgram per liter. Samples are preserved by filtration, the addition of 60 grams NaCl, and storage at 4 degrees Celsius. The laboratory has established a sample-holding time (prior to sample extraction) of 14 days from the date of sample collection until a statistically accepted method can be used to determine the effectiveness of these sample-preservation procedures.

Water-Resources Investigations Report↗

USGS1995

Relations between pesticide use and riverine flux in the Mississippi River Basin

In an intensive subcontimental study of pesticides in surface waters of the United States, concentrations of 26 high-use pesticides were measured at nine sites in the Mississippi River basin from May 1991 through March 1992. Calculated total fluxes were combined with agricultural-use data to estimate the percentage of applied pesticide reaching the mouths of the Mississippi River and six major tributaries. For most pesticides, the riverine flux was less than 2% of the mass applied agriculturally. The insecticide diazinon was detected frequently in rivers draining the three basins with the highest population densities, apparently as a result of urban use.

Mississippi River basin↗

USGS1995

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory-Determination of pesticides in water by C-18 solid-phase extraction and capillary-column gas chromatography/mass spectrometry with selected-ion monitoring

A method for the isolation of 41 pesticides and pesticide metabolites in natural-water samples using C-18 solid-phase extraction and determination by capillary-column gas chromatography/mass spectrometry with selected-ion monitoring is described. Water samples are filtered to remove suspended particulate matter and then are pumped through disposable solid-phase extraction columns containing octadecyl-bonded porous silica to extract the pesticides. The columns are dried using carbon dioxide or nitrogen gas, and adsorbed pesticides are removed from the columns by elution with 3.0 milliliters of hexane-isopropanol (3:1). Extracted pesticides are determined by capillary- column gas chromatography/mass spectrometry with selected-ion monitoring of three characteristic ions. The upper concentration limit is 4 micrograms per liter (g/L) for most pesticides, with the exception of widely used corn herbicides--atrazine, alachlor, cyanazine, and metolachlor--which have upper concentration limits of 20 g/L. Single- operator method detection limits in reagent-water samples range from 0.001 to 0.018 g/L. Average short-term single-operator precision in reagent- water samples is 7 percent at the 0.1- and 1.0-g/L levels and 8 percent at the 0.01-g/L level. Mean recoveries in reagent-water samples are 73 percent at the 0.1- and 1.0-g/L levels and 83 percent at the 0.01-g/L level. The estimated holding time for pesticides after extraction on the solid-phase extraction columns was 7 days. An optional on-site extraction procedure allows for samples to be collected and processed at remote sites where it is difficult to ship samples to the laboratory within the recommended pre-extraction holding time.

Open-File Report↗