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Michael T. Meyer

Publications and source records attributed to Michael T. Meyer.

At least 55 records · Page 3Linked to original sources

Use and environmental occurrence of pharmaceuticals in freestall dairy farms with manured forage fields

Environmental releases of antibiotics from concentrated animal feeding operations (CAFOs) are of increasing regulatory concern. This study investigates the use and occurrence of antibiotics in dairy CAFOs and their potential transport into first-encountered groundwater. On two dairies we conducted four seasonal sampling campaigns, each across 13 animal production and waste management systems and associated environmental pathways: application to animals, excretion to surfaces, manure collection systems, soils, and shallow groundwater. Concentrations of antibiotics were determined using on line solid phase extraction (OLSPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) for water samples, and accelerated solvent extraction (ASE) LC/MS/MS with ESI for solid samples. A variety of antibiotics were applied at both farms leading to antibiotics excretion of several hundred grams per farm per day. Sulfonamides, tetracyclines, and their epimers/isomers, and lincomycin were most frequently detected. Yet, despite decades of use, antibiotic occurrence appeared constrained to within farm boundaries. The most frequent antibiotic detections were associated with lagoons, hospital pens, and calf hutches. When detected below ground, tetracyclines were mainly found in soils, whereas sulfonamides were found in shallow groundwater reflecting key differences in their physicochemical properties. In manure lagoons, 10 compounds were detected including tetracyclines and trimethoprim. Of these 10, sulfadimethoxine, sulfamethazine, and lincomycin were found in shallow groundwater directly downgradient from the lagoons. Antibiotics were sporadically detected in field surface samples on fields with manure applications, but not in underlying sandy soils. Sulfadimethoxine and sulfamethazine were detected in shallow groundwater near field flood irrigation gates, but at highly attenuated levels.

Environmental Science & Technology

Tet and sul antibiotic resistance genes in livestock lagoons of various operation type, configuration, and antibiotic occurrence

Although livestock operations are known to harbor elevated levels of antibiotic resistant bacteria, few studies have examined the potential of livestock waste lagoons to reduce antibiotic resistance genes (ARGs). The purpose of this study was to determine the prevalence and examine the behavior of tetracycline [tet(O) and tet(W)] and sulfonamide [sul(I) and su/(II)] ARGsin a broad cross-section of livestock lagoons within the same semiarid western watershed. ARGs were monitored for one year in the water and the settled solids of eight lagoon systems by quantitative polymerase chain reaction. In addition, antibiotic residues and various bulk water quality constituents were analyzed. It was found that the lagoons of the chicken layer operation had the lowest concentrations of both tet and sul ARGs and low total antibiotic concentrations, whereas su ARGs were highest in the swine lagoons, which generally corresponded to the highest total antibiotic concentrations. A marginal benefit of organic and small dairy operations also was observed compared to conventional and large dairies, respectively. In all lagoons, su ARGs were observed to be generally more recalcitrant than tet ARGs. Also, positive correlations of various bulk water quality constituents were identified with tet ARGs but not sul ARGs. Significant positive correlations were identified between several metals and tet ARGs, but Pearson's correlation coefficients were mostly lower than those determined between antibiotic residues and ARGs. This study represents a quantitative characterization of ARGs in lagoons across a variety of livestock operations and provides insight into potential options for managing antibiotic resistance emanating from agricultural activities.

Environmental Science & Technology

Antibiotic fate and transport in three effluent-dominated Ozark streams

Antibiotic transport downstream from a wastewater treatment plant effluent discharge was evaluated along stream reaches on Mud Creek, Spring Creek, and Decatur Branch in northwestern Arkansas, USA. Water and streambed samples were collected during August and September 2006 and analyzed for multiple antibiotics representing five classes (beta-lactams, macrolides, quinolones, sulfonamides, and tetracyclines). Antibiotics within the classes macrolides, quinolones, and sulfonamides were detected in the water column at all three stream reaches. Several of these same antibiotics, as well as antibiotics from the class tetracycline, were measured in streambed material at quantities significantly greater than those observed in the water column. Pseudo-partitioning coefficients ranged from 4 to >8000 L kg −1 . Most of the antibiotics studied were significantly retained in the reaches at Mud Creek and Spring Creek and traveled kilometer-scale distances ( S net , 3.3–20.2 km) with low uptake velocities ( v f-net "> vf-net , 2.9–16.1 × 10 −6 m s −1 ) and rates ( U net 0.01–37.9 × 10 −6 μg m −2 s −1 ). Some antibiotics increased in concentration downstream from the effluent discharge at Decatur Branch, suggesting possible release from within the fluvial channel or additional sources along the stream reach. In general, antibiotics traveled kilometer-scale distances before significant dilution occurred through in-stream processes (e.g., advection, dispersion, sorption, uptake and/or degradation) within the fluvial channel of these effluent-dominated streams.

Arkansas

Determination of antibiotics in sewage from hospitals, nursery and slaughter house, wastewater treatment plant and source water in Chongqing region of Three Gorge Reservoir in China

Sewage samples from 4 hospitals, 1 nursery, 1 slaughter house, 1 wastewater treatment plant and 5 source water samples of Chongqing region of Three Gorge Reservoir were analyzed for macrolide, lincosamide, trimethoprim, fluorouinolone, sulfonamide and tetracycline antibiotics by online solid-phase extraction and liquid chromatography-tandem mass spectrometry. Results showed that the concentration of ofloxacin (OFX) in hospital was the highest among all water environments ranged from 1.660 μg/L to 4.240 μg/L and norfloxacin (NOR, 0.136–1.620 μg/L), ciproflaxacin (CIP, ranged from 0.011 μg/L to 0.136 μg/L), trimethoprim (TMP, 0.061–0.174 μg/L) were commonly detected. Removal range of antibiotics in the wastewater treatment plant was 18–100% and the removal ratio of tylosin, oxytetracycline and tetracycline were 100%. Relatively higher removal efficiencies were observed for tylosin (TYL), oxytetracycline (OXY) and tetracycline (TET)(100%), while lower removal efficiencies were observed for Trimethoprim (TMP, 1%), Epi-iso-chlorotetracycline (EICIC, 18%) and Erythromycin-H 2 O (ERY-H 2 O, 24%). Antibiotics were removed more efficiently in primary treatment compared with those in secondary treatment.

Chongqing region, Three Gorge Reservoir

Phytoestrogens and mycotoxins in Iowa streams: An examination of underinvestigated compounds in agricultural basins

This study provides the first broad-scale investigation on the spatial and temporal occurrence of phytoestrogens and mycotoxins in streams in the United States. Fifteen stream sites across Iowa were sampled five times throughout the 2008 growing season to capture a range of climatic and crop-growth conditions. Basin size upstream from sampling sites ranged from 7 km 2 to >836,000 km 2 Atrazine (herbicide) also was measured in all samples as a frame-of-reference agriculturally derived contaminant. Target compounds were frequently detected in stream samples: atrazine (100%), formononetin (80%), equol (45%), deoxynivalenol (43%), daidzein (32%), biochanin A (23%), zearalenone (13%), and genistein (11%). The nearly ubiquitous detection of formononetin (isoflavone) suggests a widespread agricultural source, as one would expect with the intense row crop and livestock production present across Iowa. Conversely, the less spatially widespread detections of deoxynivalenol (mycotoxin) suggest a more variable source due to the required combination of proper host and proper temperature and moisture conditions necessary to promote Fusarium spp. infections. Although atrazine concentrations commonly exceeded 100 ng L -1 (42/75 measurements), only deoxynivalenol (6/56 measurements) had concentrations that occasionally exceeded this level. Temporal patterns in concentrations varied substantially between atrazine, formononetin, and deoxynivalenol, as one would expect for contaminants with different source inputs and processes of formation and degradation. The greatest phytoestrogen and mycotoxin concentrations were observed during spring snowmelt conditions. Phytoestrogens and mycotoxins were detected at all sampling sites regardless of basin size. The ecotoxicological effects from long-term, low-level exposures to phytoestrogens and mycotoxins or complex chemicals mixtures including these compounds that commonly take place in surface water are poorly understood and have yet to be systematically investigated in environmental studies.

Iowa

Occurrence of antibiotic compounds in source water and finished drinking water from the upper Scioto River Basin, Ohio, 2005-6

The occurrence of antibiotics in surface water and groundwater in urban basins has become a topic of increasing interest in recent years. Little is known about the occurrence, fate, or transport of these compounds and the possible health effects in humans and aquatic life. The U.S. Geological Survey, in cooperation with the City of Columbus, Division of Power and Water, did a study to provide a synoptic view of the occurrence of antibiotics in source and finished waters in the upper Scioto River Basin. Water samples were collected seasonally-winter (December 2005), spring (May 2006), summer (August 2006) and fall (October 2006)-at five surface-water sites, one groundwater site, and three water-treatment plants (WTPs). Within the upper Scioto River Basin, sampling at each WTP involved two sampling sites: a source-water intake site and a finished-water site. One or more antibiotics were detected at 11 of the 12 sampling sites. Of the 49 targeted antibiotic compounds, 12 (24 percent) were detected at least one time for a total of 61 detections overall. These compounds were azithromycin, tylosin, erythromycin-H2O, erythromycin, roxithromycin, ciprofloxacin, ofloxacin, sulfamethazine, sulfamethoxazole, iso-chlorotetracycline, lincomycin, and trimethoprim. Detection results were at low levels, with an overall median of 0.014 (u or mu)g/L. Hap Cremean WTP had the fewest detections, with two source-water detections of sulfamethoxazole and azithromycin and no detections in the finished water. Of the total of 61 detections, 31 were in the winter sample run. Sulfamethoxazale and azithromycin detections represent 41 percent of all antibiotic detections. Azithromycin was detected only in the winter sample. Some antibiotics, such as those in the quinoline and tetracycline families, dissipate more quickly in warm water, which may explain why they were detected in the cool months (winter, spring, and fall) and not in the summer. Antibiotic data collected during this study were compared to antibiotic data collected in previous national, regional, and local studies. Many of the same antibiotic compounds detected in the upper Scioto River Basin also were detected in those investigations.

Ohio

Effect of diet on fecal and urinary estrogenic activity

The United States Environmental Protection Agency has identified estrogens from animal feeding operations as a major environmental concern, but few data are available to quantify the excretion of estrogenic compounds by dairy cattle. The objectives of this study were to quantify variation in estrogenic activity in feces and urine due to increased dietary inclusion of phytoestrogens. Ten Holstein heifers were assigned to 2 groups balanced for age and days pregnant; groups were randomly assigned to treatment sequence in a 2-period crossover design. Dietary treatments consisted of grass hay or red clover hay, and necessary supplements. Total collection allowed for sampling of feed refusals, feces, and urine during the last 4 d of each period. Feces and urine samples were pooled by heifer and period, and base extracts were analyzed for estrogenic activity (estrogen equivalents) using the yeast estrogen screen bioassay. Feces and urine samples collected from 5 heifers were extracted and analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to quantify excretion of 7 phytoestrogenic compounds. Excretion of 17-β estradiolequivalents in urine was higher and tended to be higher in feces for heifers fed red clover hay (84.4 and 120.2 mg/d for feces and urine, respectively) compared with those fed grasshay (57.4 and 35.6 mg/d). Analysis by LC-MS/MS indicated greater fecal excretion of equol, genistein, daidzein, coumestrol, and formononetin by heifers fed red clover hay (1634, 29.9, 96.3, 27.8, and 163 mg/d, respectively) than heifers fed grass hay (340, 3.0, 46.2, 8.8, and 18.3 mg/d, respectively). Diet had no effect on fecal biochanin A or 2-carbethoxy-5, 7-dihydroxy-4’-methoxyisoflavone. Four phytoestrogens were detected in urine (2-carbethoxy-5, 7-dihydroxy-4’-methoxyisoflavone, daidzein, equol, and formononetin) and their excretion was not affected by diet. Identifying sources of variation in estrogenic activity of manure will aid in the development of practices to reduce environmental estrogen accumulation.

Journal of Dairy Science

Fate of trace organic compounds during vadose zone soil treatment in an onsite wastewater system

During onsite wastewater treatment, trace organic compounds are often present in the effluents applied to subsurface soils for advanced treatment during vadose zone percolation and groundwater recharge. The fate of the endocrine-disrupting surfactant metabolites 4-nonylphenol (NP), 4-nonylphenolmonoethoxylate (NP1EO), and 4-nonylphenolmonoethoxycarboxylate (NP1EC), metal-chelating agents ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA), antimicrobial agent triclosan, stimulant caffeine, and antibiotic sulfamethoxazole during transport through an unsaturated sandy loam soil was studied at a field-scale test site. To assess the effects of effluent quality and hydraulic loading rate (HLR) on compound fate in the soil profile, two effluents (septic tank or textile biofilter) were applied at two design HLRs (2 or 8 cm/d). Chemical concentrations were determined in the two effluents and soil pore water at 60, 120, and 240 cm below the soil infiltrative surface. Concentrations of trace organic compounds in septic tank effluent were reduced by more than 90% during transport through 240 cm (often within 60 cm) of soil, likely due to sorption and biotransformation. However, the concentration of NP increased with depth in the shallow soil profile. Additional treatment of anaerobic septic tank effluent with an aerobic textile biofilter reduced effluent concentrations of many compounds, but generally did not affect any changes in pore water concentrations. The soil profile receiving septic tank effluent (vs. textile biofilter effluent) generally had greater percent removal efficiencies. EDTA, NP, NP1EC, and sulfamethoxazole were measured in soil pore water, indicating the ability of some trace organic compounds to reach shallow groundwater. Risk is highly dependent on the degree of further treatment in the saturated zone and the types and proximity of uses for the receiving groundwater environment.

Environmental Toxicology and Chemistry

Fate of sulfamethoxazole, 4-nonylphenol, and 17β-estradiol in groundwater contaminated by wastewater treatment plant effluent

Organic wastewater contaminants (OWCs) were measured in samples collected from monitoring wells located along a 4.5-km transect of a plume of groundwater contaminated by 60 years of continuous rapid infiltration disposal of wastewater treatment plant effluent. Fifteen percent of the 212 OWCs analyzed were detected, including the antibiotic sulfamethoxazole (SX), the nonionic surfactant degradation product 4-nonylphenol (NP), the solvent tetrachloroethene (PCE), and the disinfectant 1,4-dichlorobenzene (DCB). Comparison of the 2005 sampling results to data collected from the same wells in 1985 indicates that PCE and DCB are transported more rapidly in the aquifer than NP, consistent with predictions based on compound hydrophobicity. Natural gradient in situ tracer experiments were conducted to evaluate the subsurface behavior of SX, NP, and the female sex hormone 17β-estradiol (E2) in two oxic zones in the aquifer: (1) a downgradient transition zone at the interface between the contamination plume and the overlying uncontaminated groundwater and (2) a contaminated zone located beneath the infiltration beds, which have not been loaded for 10 years. In both zones, breakthrough curves for the conservative tracer bromide (Br − ) and SX were nearly coincident, whereas NP and E2 were retarded relative to Br − and showed mass loss. Retardation was greater in the contaminated zone than in the transition zone. Attenuation of NP and E2 in the aquifer was attributed to biotransformation, and oxic laboratory microcosm experiments using sediments from the transition and contaminated zones show that uniform-ring-labeled 14 C 4-normal-NP was biodegraded more rapidly (30−60% recovered as 14 CO 2 in 13 days) than 4- 14 C E2 (20−90% recovered as 14 CO 2 in 54 days). There was little difference in mineralization potential between sites.

Massachusetts

The Evolution of analytical technology and its impact on water-quality studies for selected herbicides and their degradation products in water

This chapter aims to describe advances in analytical instrumentation and methods for the analyses of herbicides and their degradation products and to assess their impact on major findings of broad surveys of herbicides in water conducted by the U.S. Geological Survey(USGS) over the last two decades. Standards for water purity have been set and continually revised by governments as new contaminants that may impact human health are identified. These water-purity standards have brought continued improvement in water quality of existing water sources by reducing the amount of pollution in drinking water, treating wastewater, diverting wastewater discharge from drinking-water supplies, implementing new filtration practices, and other innovative techniques. It is vital that state-of-the-art instrumentation for analyzing organic contaminants continually be introduced into the marketplace the advancement of analytical instrumentation has given scientists the capability to continually broaden their studies of the fate of herbicides and their degradation products over the last two decades. Studies by many scientists have continually expanded the knowledge of the occurrence, persistence, and transport of herbicides and their degradation products in the hydrologic environment.

Book chapter

Determination of glyphosate, its degradation product aminomethylphosphonic acid, and glufosinate, in water by isotope dilution and online solid-phase extraction and liquid chromatography/tandem mass spectrometry

The U.S. Geological Survey method (0-2141-09) presented is approved for the determination of glyphosate, its degradation product aminomethylphosphonic acid (AMPA), and glufosinate in water. It was was validated to demonstrate the method detection levels (MDL), compare isotope dilution to standard addition, and evaluate method and compound stability. The original method USGS analytical method 0-2136-01 was developed using liquid chromatography/mass spectrometry and quantitation by standard addition. Lower method detection levels and increased specificity were achieved in the modified method, 0-2141-09, by using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The use of isotope dilution for glyphosate and AMPA and pseudo isotope dilution of glufosinate in place of standard addition was evaluated. Stable-isotope labeled AMPA and glyphosate were used as the isotope dilution standards. In addition, the stability of glyphosate and AMPA was studied in raw filtered and derivatized water samples. The stable-isotope labeled glyphosate and AMPA standards were added to each water sample and the samples then derivatized with 9-fluorenylmethylchloroformate. After derivatization, samples were concentrated using automated online solid-phase extraction (SPE) followed by elution in-line with the LC mobile phase; the compounds separated and then were analyzed by LC/MS/MS using electrospray ionization in negative-ion mode with multiple-reaction monitoring. The deprotonated derivatized parent molecule and two daughter-ion transition pairs were identified and optimized for glyphosate, AMPA, glufosinate, and the glyphosate and AMPA stable-isotope labeled internal standards. Quantitative comparison between standard addition and isotope dilution was conducted using 473 samples analyzed between April 2004 and June 2006. The mean percent difference and relative standard deviation between the two quantitation methods was 7.6 plus or minus 6.30 (n = 179), AMPA 9.6 plus or minus 8.35 (n = 206), and glufosinate 9.3 plus or minus 9.16 (n = 16). The analytical variation of the method, comparison of quantitation by isotope dilution and multipoint linear regressed standard curves, and method detection levels were evaluated by analyzing six sets of distilled-water, groundwater, and surface-water samples spiked in duplicate at 0.0, 0.05, 0.10 and 0.50 microgram per liter and analyzed on 6 different days during 1 month. The grand means of the normalized concentration percentage recovery for glyphosate, AMPA, and glufosinate among all three matrices and spiked concentrations ranged from 99 to 114 plus or minus 2 to 7 percent of the expected spiked concentration. The grand mean of the percentage difference between concentrations calculated by standard addition and linear regressed multipoint standard curves ranged from 8 to 15 plus or minus 2 to 9 percent for the three compounds. The method reporting levels calculated from all the 0.05- microgram per liter spiked samples were 0.02 microgram per liter for all three compounds. Compound stability experiments were conducted on 10 samples derivatized four times for periods between 136 to 269 days. The glyphosate and AMPA concentrations remained relatively constant in samples held up to 136 days before derivatization. The half life of glyphosate varied from 169 to 223 days in the underivatized samples. Derivatized samples were analyzed the day after derivitization, and again 54 and 64 days after derivatization. The derivatized samples analyzed at days 52 and 64 were within 20 percent of the concentrations of the derivatized samples analyzed the day after derivatization.

Techniques and Methods

Water-quality data for pharmaceuticals and other organic wastewater contaminants in ground water and in untreated drinking water sources in the United States, 2000-01

This report presents water-quality data from two nationwide studies on the occurrence and distribution of organic wastewater contaminants. These data are part of the continuing effort of the U.S. Geological Survey Toxic Substances Hydrology Program to collect baseline information on the environmental occurrence of pharmaceuticals and other organic wastewater contaminants. In 2000, samples were collected from 47 ambient ground-water sites (not drinking-water wells) in 18 states and analyzed for 65 organic wastewater contaminants. In the summer of 2001, samples were collected from 74 sources of raw, untreated, drinking water in 25 states and Puerto Rico and analyzed for 100 organic wastewater contaminants. These sources comprise 25 ground-water and 49 surface-water sources of drinking water serving populations ranging from one family to more than 8 million people. Site selection for both studies focused on areas known or suspected to contain sources of animal and/or human wastewater. The five most frequently detected compounds in samples collected from ambient ground-water sites are N,N-diethyltoluamide (35 percent, insect repellant), bisphenol A (30 percent, plasticizer), tri(2-chloroethy) phosphate (30 percent, fire retardant), sulfamethoxazole (23 percent, veterinary and human antibiotic), and 4-octylphenol monoethoxylate (19 percent, detergent metabolite). The five most frequently detected organic wastewater contaminants in samples of untreated drinking water from surface-water sources are cholesterol (59 percent, natural sterol), metolachlor (53 percent, herbicide), cotinine (51 percent, nicotine metabolite), β-sitosterol (37 percent, natural plant sterol), and 1,7-dimethylxanthine (27 percent, caffeine metabolite). The five most frequently detected organic wastewater contaminants in samples of untreated drinking water from ground-water sources are tetrachloroethylene (24 percent, solvent), carbamazepine (20 percent, pharmaceutical), bisphenol A (20 percent, plasticizer), 1,7-dimethylxanthine (16 percent, caffeine metabolite), and tri(2-chloroethyl) phosphate (12 percent, fire retardant).

Open-File Report

Comparison of two cell lysis procedures for recovery of microcystins in water samples from silver lake in Dover, Delaware, with microcystin producing cyanobacterial accumulations

A collaboration was developed between Abraxis, LLC, the State of Delaware Department of Natural Resources and Environmental Control Division of Water Resources Environmental Laboratory, the University of Delaware, and the United States Geological Survey to investigate the efficacy of the QuikLyse procedure developed by Abraxis, LLC as an alternative cell-lysis technique suitable for use with an existing liquid chromatography/tandem mass spectrometry research method developed at the United States Geological Survey Organic Geochemistry Research Laboratory to analyze cyanotoxins. A comparison of three sequential freeze/thaw cycles versus QuikLyse, a proprietary chemical lysis procedure was conducted on four water samples collected from Silver Lake in Dover, Delaware. Results from the Abraxis Microcystins-DM enzyme-linked immunosorbent assay and liquid chromatography/tandem mass spectrometry were tabulated as a function of the cell lysis technique. Stastical comparison of percent relative standard deviations showed no significant difference (alpha = 0.05) between both cell-lysis techniques when measured by enzyme-linked immunosorbent assay or liquid chromatography/tandem mass spectrometry for three of the four samples.

Delaware

Guidelines for design and sampling for cyanobacterial toxin and taste-and-odor studies in lakes and reservoirs

Cyanobacteria and associated toxins and taste-and-odor compounds are of increasing environmental concern. However, consistent guidelines for the development of studies assessing cyanobacterial toxins and taste-and-odor compounds presently are not available. This report provides guidance for the development of scientific studies of cyanobacteria and associated by-products in lakes and reservoirs. Topics include: background information on cyanobacteria, toxins, and taste-and-odor compounds; spatial and temporal considerations that are unique to the cyanobacteria in lakes and reservoirs; common study types, objectives, and approaches for studies of cyanobacteria and associated toxins and taste-and-odor compounds; general guidelines for collecting samples; and information on sample handling, preparation, processing, and shipping.

Scientific Investigations Report

Chapter A7. Section 7.5. Cyanobacteria in lakes and reservoirs: Toxin And taste-and-odor sampling guidelines

Cyanobacteria (also referred to as blue-green algae) cause a multitude of water-quality concerns, including the potential to produce toxins and taste-and-odor compounds. Toxins and taste-and-odor compounds may cause significant economic and public health concerns, and are of particular interest in lakes, reservoirs, and rivers that are used for drinking-water supply, recreation, or aquaculture. The purpose of NFM 7.5 is to provide guidelines for collecting, processing, and handling samples to be analyzed for cyanobacterial community composition (enumeration and identification) and total, particulate, and dissolved cyanobacterial toxins and taste-and-odor compounds in lakes and reservoirs (sections 7.5.5 through 7.5.9). Sections 7.5.1 through 7.5.4, however, are designed to provide some background information about cyanobacteria, including typical study designs and objectives related to the spatial and temporal occurrence of cyanobacteria (modified from Graham and others, 2008), in order to provide a useful context for sampling activities. The information presented here pertains to the occurrence of planktonic (free-floating) cyanobacteria in lakes and reservoirs. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under 'New Publications of the U.S. Geological Survey.'

Techniques of Water-Resources Investigations

Comparison of fate and transport of isoxaflutole to atrazine and metolachlor in 10 Iowa rivers

Isoxaflutole (IXF), a newer low application rate herbicide, was introduced for weed control in corn (Zea mays) to use as an alternative to widely applied herbicides such as atrazine. The transport of IXF in streamwater has not been well-studied. The fate and transport of IXF and two of its degradation products was studied in 10 Iowa rivers during 2004. IXF rapidly degrades to the herbicidally active diketonitrile (DKN), which degrades to a biologically inactive benzoic acid (BA) analogue. IXF was detected in only four, DKN in 56, and BA in 43 of 75 samples. The concentrations of DKN and BA were approximately 2 orders of magnitude less than those of the commonly detected triazine and acetamide herbicides and their degradation products. Concentrations of IXF, DKN, and BA were highest during the May through June postplanting period. The concentration ratio of BA/DKN was similar to the deethylatrazine/atrazine ratio with smaller ratios occurring during May and June. The relative temporal variation of DKN and BA was similar to that observed for atrazine and deethylatrazine. This study shows that low application rate herbicides can have similar temporal transport patterns in streamwater as compared to more widely applied herbicides but at lower concentrations.

Iowa

Do pharmaceuticals, pathogens, and other organic waste water compounds persist when waste water is used for recharge?

A proof-of-concept experiment was devised to determine if pharmaceuticals and other organic waste water compounds (OWCs), as well as pathogens, found in treated effluent could be transported through a 2.4 m soil column and, thus, potentially reach ground water under recharge conditions similar to those in arid or semiarid climates. Treated effluent was applied at the top of the 2.4 m long, 32.5 cm diameter soil column over 23 days, Samples of the column inflow were collected from the effluent storage tank at the beginning (T begin ) and end (T end ) of the experiment, and a sample of the soil column drainage at the base of the column (B end ) was collected at the end of the experiment. Samples were analyzed for 131 OWCs including veterinary and human antibiotics, other prescription and nonprescription drugs, widely used household and industrial chemicals, and steroids and reproductive hormones, as well as the pathogens Salmonella and Legionella . Analytical results for the two effluent samples taken at the beginning (T begin ) and end (T end ) of the experiment indicate that the number of OWCs detected in the column inflow decreased by 25% (eight compounds) and the total concentration of OWCs decreased by 46% while the effluent was in the storage tank during the 23-day experiment. After percolating through the soil column, an additional 18 compounds detected in T end (67% of OWCs) were no longer detected in the effluent (B end ) and the total concentration of OWCs decreased by more than 70%. These compounds may have been subject to transformation (biotic and abiotic), adsorption, and (or) volatilization in the storage tank and during travel through the soil column. Eight compounds—carbamazapine; sulfamethoxazole; benzophenone; 5-methyl-1H-benzotriazole; N,N-diethyltoluamide; tributylphosphate; tri(2-chloroethyl) phosphate; and cholesterol—were detected in all three samples indicating they have the potential to reach ground water under recharge conditions similar to those in arid and semiarid climates. Results from real-time polymerase chain reactions demonstrated the presence of Legionella in all three samples. Salmonella was detected only in T begin , suggesting that the bacteria died off in the effluent storage tank over the period of the experiment. This proof-of-concept experiment demonstrates that, under recharge conditions similar to those in arid or semiarid climates, some pharmaceuticals, pathogens, and other OWCs can persist in treated effluent after soil-aquifer treatment.

Ground Water Monitoring and Remediation

Pharmaceuticals and other organic wastewater contaminants within a leachate plume downgradient of a municipal landfill

Ground water samples collected from the Norman Landfill research site in central Oklahoma were analyzed as part of the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program's national reconnaissance of pharmaceuticals and other organic waste water contaminants (OWCs) in ground water. Five sites, four of which are located downgradient of the landfill, were sampled in 2000 and analyzed for 76 OWCs using four research methods developed by the USGS. OWCs were detected in water samples from all of the sites sampled, with 22 of the 76 OWCs being detected at least once. Cholesterol (a plant and animal steroid), was detected at all five sites and was the only compound detected in a well upgradient of the landfill. N,Ndiethyltoluamide (DEET used in insect repellent) and tri(2-chloroethyl) phosphate (fire-retardant) were detected in water samples from all four sites located within the landfill-derived leachate plume. The sites closest to the landfill had more detections and greater concentrations of each of the detected compounds than sites located farther away. Detection of multiple OWCs occurred in the four sites located within the leachate plume, with a minimum of four and a maximum of 17 OWCs detected. Because the landfill was established in the 1920s and closed in 1985, many compounds detected in the leachate plume were likely disposed of decades ago. These results indicate the potential for long-term persistence and transport of some OWCs in ground water.

Oklahoma