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Filters Date Range Past year (6) Past month (1) Past week (0) Past day (0) Custom range... To   Search Contacts Michael S Gross U.S. Geological Survey - ScienceBase U.S. Geological Survey Water Resources Matthew Uychutin More... Categories Data (20) Tag Types Theme (22) Place (17) USGS Scientific Topic Keyword (18) Harvest Set (21) Tag Schemes None (8) National Agricultural Library Thesaurus (11) USGS Thesaurus (15) ISO 19115 Topic Category (19) Common Geographic Areas (7) NAL Agricultural Thesaurus (2) USGS Common Geographic Areas (5) More... View Results as: JSON ATOM CSV

Evaluation of ELISA for the Analysis of Imidacloprid in Plasma, Liver, and Fecal Matter Neonicotinoids have become the most widely used insecticides in world with rapid growth in applications as seed coatings. Nontarget organisms are exposed to concentrated levels of pesticidal active ingredients through ingestion of treated seeds. To better understand pesticide fate, analytical methods are necessary to rapidly screen and accurately quantitate contaminants in environmental and biological matrices. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is commonly employed for neonicotinoid analyses but requires expensive analytical instrumentation and potentially laborious sample preparation. Enzyme-linked immunosorbent assays (ELISAs) are efficient and sensitive alternative methods for neonicotinoid... Categories: Data; Tags: Coturnix japonica, Environmental Health, USGS Science Data Catalog (SDC), United States, environment, All tags... enzyme-linked immunosorbent assay, high performance liquid chromatography, mass spectrometry, metabolites, neonicotinoid insecticides, pesticide residues, Fewer tags Insecticide and fungicide concentrations in irrigation runoff and soils from a lettuce field in the Salinas Valley, California, 2019 and 2020 Irrigation runoff and soil samples were collected from a lettuce field located at the USDA-ARS Spence Research farm in the Salinas Valley, California to measure neonicotinoid insecticides (clothianidin and imidacloprid) and a fungicide (azoxystrobin) applied via coated seed and drench treatments. The field trial was designed to evaluate four treatments with replication: 1) control, untreated seed, 2) imidacloprid treated seed, 3) clothianidin treated seed, and 4) azoxystrobin treated seed with an imidacloprid drench. Samples were collected from each treatment over two lettuce growing seasons: August to October 2019 and September to October 2020. Runoff samples were collected over both growing seasons during 6 irrigation... Categories: Data; Tags: California, Salinas, Soil Sciences, USGS Science Data Catalog (SDC), Water Quality, All tags... Water Resources, contamination and pollution, environment, fungicides, insecticides, irrigation, pesticide and herbicide contamination, pesticides, seed treatment, soil drenching, soil resources, surface water quality, Fewer tags Pesticide Concentrations Measured in Zooplankton Samples Collected from the Sacramento River and Yolo Bypass, California, 2021 Zooplankton samples were collected at one site upstream of the Yolo Bypass in Northern California, three sites within the Bypass, and at a comparison site on the Sacramento River below the city of Sacramento and analyzed for a large suite of current-use pesticides and degradates. Samples were collected every two weeks from early August 2021 to mid-October 2021. Samples were collected by towing a 150-micron conical plankton net for 5 minutes by boat at each site. In the laboratory, zooplankton samples were filtered through a 63-micrometer sieve to separate the zooplankton and vegetation/detritus from the water. Large sticks, twigs, rocks, and leaves were rinsed with organic free water into the sieve and then discarded.... Categories: Data; Tags: California, Environmental Health, Hydrology, Sacramento, USGS Science Data Catalog (SDC), All tags... Water Quality, Zooplankton, environment, pesticide and herbicide contamination, Fewer tags Pesticide concentrations in bees and other matrices collected from sunflower fields (with and without a neonicotinoid seed treatment) near Sacramento, California Hybrid sunflower production occurs near Sacramento in Northern California where seed treatments are commonly used. In this study, four locations were sampled in 2016 as matched pairs; half of each field was sown with thiamethoxam treated seed and half without. In addition to the thiamethoxam seed treatment, all seeds were coated with two fungicides, fludioxonil and mefenoxam/metalaxyl. Both wild bee and honey bee pesticide exposure was assessed by analyzing field soil, sunflower pollen and nectar, honey bees (pollen and nectar foraging) and a sunflower specialist wild bee, Melissodes agilis. Samples were extracted via pressurized liquid extraction (except nectar which underwent a room temperature solvent extraction)... Categories: Data; Tags: California, Environmental Health, USGS Science Data Catalog (SDC), environment, fungicides, All tags... herbicides, insecticides, non-Apis pollinators, pesticide and herbicide contamination, pesticides, pollinators, pollinators, Fewer tags Current-use pesticides in tree swallow (Tachycineta bicolor) prey Analysis of biological tissues or direct sources of food may better characterize exposure of non-target organisms to current-use pesticides. Food boluses were collected from tree swallow (Tachycineta bicolor) nestlings using a non-lethal, ligature method and were composited based on nest. The ligatures, which prevented the bolus from being swallowed, were placed on nestlings for 1 h until samples were collected. Samples in 2016 were collected from nestlings at 6 days and 12 days post-hatch whereas 2018 samples were collected from nestlings at 12 days post-hatch. Furthermore, in 2016 and 2018, insects commonly consumed by tree swallows were collected via sweep net and composited based on suborder (Brachycera, Nematocera,... Categories: Data; Tags: Burr, Colonsay, Environmental Health, Humboldt, North America, All tags... Prairie Pothole Region, Prairie Pothole Region, Saskatchewan, St-Denis, Tachycineta bicolor, USGS Science Data Catalog (SDC), bolus, environment, gas chromatography, high performance liquid chromatography, insects, mass spectrometry, nestlings, pesticide residues, Fewer tags Analysis of Polyphenols in Water Primrose (Ludwigia hexapetala) Plants from the Sacramento-San Joaquin Delta of California Water primrose (Ludwigia hexapetala) is an invasive aquatic plant that has rapidly increased in coverage throughout the Sacramento-San Joaquin Delta. Water primrose has invaded wetlands and may contribute towards mortality of tules (Schoenoplectus spp.) and cattails (Typha spp.). Little research has been completed on the mechanisms responsible for marsh loss, but previous studies have suggested that water primrose contains allelopathic chemicals that could cause plant mortality. Three major allelopathic polyphenols (myricitrin, prunin, and quercitrin) previously identified in L. hexapetala leaves were measured in leaf, water, and soil samples from Delta marshes infested with water primrose. Samples were collected... Categories: Data; Tags: Big Break, Ecology, Environmental Health, Latham Slough, Liberty Island, All tags... North America, Rhode Island, Sacramento-San Joaquin Delta, San Joaquin Delta, Sherman Lake, USGS Science Data Catalog (SDC), Venice Cut, Water Quality, ecological competition, environment, invasive species, liquid chromatography, mass spectroscopy, water quality, Fewer tags Nitrapyrin, 6-CPA, and herbicide concentrations in agricultural soils, subsurface drains, and corresponding streams in the Midwestern US Nitrapyrin is a nitrification inhibitor that is co-applied with N-fertilizer in agroecosystems. Over the course of one year (March 2016 to June 2017), 192 water samples from seven streams across Iowa and Illinois were analyzed for nitrapyrin, its degradate 6-chloropicolinic acid (6-CPA), and three widely used herbicides acetochlor, atrazine, and metolachlor. Additional environmental samples were collected and analyzed in spring 2017: 63 water samples from eight subsurface drains, and 33 soil samples from a field in Iowa that received direct application of nitrapyrin (only for nitrapyrin and herbicides). Nitrapyrin was detected in all seven streams (56% detection) with concentrations ranging from 4 to 1,200 ng/L;... Tags: Corn Belt region, Environmental Health, Illinois, Iowa, USGS Science Data Catalog (SDC), All tags... United States, Water Quality, agricultural soils, agriculture, contaminant transport, ecotoxicity, herbicide, nitrapyrin, stormwater, stream discharge, tile drainage, water quality, Fewer tags Pesticide residues in monarch butterflies collected from Pacific Grove, California, USA in January 2024 In January 2024 adult monarch butterflies (Danaus plexippus (Linnaeus, 1758)) were found dead near their overwintering site in Pacific Grove, Monterey County, California, USA. Ten of the deceased monarchs (six females and four males) were collected from three sites by staff at the Pacific Grove Museum of Natural History and sent to the U.S. Geological Survey Organic Chemistry Research Laboratory for analysis. Each individual adult monarch was analyzed following methods in Black et al., 2023 and Gross et al., 2024a and 2024b for 181 pesticides and pesticide transformation products; 15 pesticides were detected and included 8 insecticides/insecticide transformation products, 2 fungicides, and 4 herbicides/herbicide... Tags: California, Environmental Health, Fungicide, Herbicide, Insecticide, All tags... Pesticide, USGS Science Data Catalog (SDC), biota, butterflies and moths, environment, pesticide and herbicide contamination, Fewer tags Multiresidue extraction of current-use pesticides from complex solid matrices using energized dispersive extraction with analysis by gas and liquid chromatography tandem mass spectroscopy A multiresidue method for solids (i.e., soil, sediment, sludge) was developed and evaluated for the analysis of pesticides and pesticide degradates. Initially, a well characterized soil was used to determine the recovery of target compounds using an Energized Dispersive Guided Extraction (EDGE) system with two extraction solvents, acetonitrile and 1:1 (v/v) hexane:acetone. Extracts were cleaned using solid-phase extraction (SPE) with graphitized carbon cartridges and three elution solvents, acetonitrile, dichloromethane, and 1:1 (v/v) dichlormethane:ethyl acetate. The individual SPE elutions from the two extraction solvents were analyzed separately via GC-MS/MS and LC-MS/MS for 210 pesticides and pesticide transformation... Categories: Data; Tags: Environmental Health, USGS Science Data Catalog (SDC), biosolids, contaminant transport, environment, All tags... gas chromatography, liquid chromatography, mass spectrometry, pesticide and herbicide contamination, sediment, soil, Fewer tags Pesticide concentrations in surface waters of the Sacramento Valley rice-growing region, 2010 Surface water samples were collected from four stream/agricultural drain sites in the Sacramento Valley of California to measure pesticides commonly applied to rice. Samples were collected weekly from May through August 2010 to capture the rice pesticide application season. Water samples were filtered (0.7 µm) and extracted via solid-phase extraction. Additionally, the filter paper was solvent extracted to measure suspended sediment-associated pesticides. Both fractions were analyzed via gas chromatography-mass spectrometry. A total of 89 pesticides and pesticide degradates were measured in the dissolved water phase, while 14 pyrethroid insecticides were measured in the suspended sediment-associated fraction (pyrethroids... Categories: Data; Tags: California, Environmental Health, Sacramento Valley, USGS Science Data Catalog (SDC), Water Quality, All tags... contamination and pollution, environment, fungicides, herbicides, insecticides, pesticide and herbicide contamination, pesticides, surface water quality, suspended material (water), water quality, Fewer tags Pesticides in pollinator tissue collected from margins near agricultural fields in Conservation Areas of Missouri Wild bee and butterfly samples were collected from the margins of agricultural fields located on five Conservation Areas in Missouri. In 2016 and 2017, samples were collected and composited by genera for a total of 90 samples. Samples were extracted via pressurized liquid extraction and solid phase extraction cleanup. Samples were analyzed for 168 pesticides and degradates using both gas and liquid chromatography-tandem mass spectrometry. Overall, 16 pesticides were detected. Pesticides detected in greater than 2% of the composite samples included: metolachlor (24%), tebuconazole (22%), atrazine (18%), imidacloprid desnitro (13%), bifenthrin (9%), flumetralin (9%), p,p’-DDD (6%), tebupirimfos (4%), fludioxonil (4%),... Categories: Data; Tags: Missouri, North America, USGS Science Data Catalog (SDC), biota, butterflies, All tags... conservation areas, environment, non-Apis pollinators, pesticide and herbicide contamination, pesticide residues, pollinators, pollinators, Fewer tags Pesticide detections in streams throughout the foothills of the Sierra Nevada range using passive samplers from 2017 to 2019 This dataset was produced from analyzing Affinisep SDB-RPS, Affinisep HLB, and Restek Resprep C18 disks that were deployed with the use of Chemcatcher® passive sampling devices. Silicone bands were also deployed and used for exploring economical methods of sampling for pesticides in surface water. Sampling assemblies were deployed in streams throughout the foothills of the Sierra Nevada range and California's northern Central Valley from 2017 to 2019. Samples were extracted in situ then eluted and concentrated at the Organic Chemistry Research Laboratory in Sacramento, CA. Samples from silicone bands were extracted via agitation in appropriate solvents. Samples were analyzed for a suite of 155 pesticides and degradates... Categories: Data; Tags: Affinisep, C18, California, Chemcatcher, Degradates, All tags... Gas Chromatography, HLB, Honcut Creek, Hydrology, Liquid Chromatography, Mass Spectrometry, North Fork Calaveras River, Oregon Creek, Pesticides, Rattlesnake Creek, Redding, Resprep, Restek, SDB-RPS, SPE, Sacramento River, Sierra Nevada, Silicone Bands, Solid Phase Extraction, South Fork American River, Surface water, USGS Science Data Catalog (SDC), United States, Water Quality, environment, inlandWaters, Fewer tags Pesticide Concentrations Measured in Zooplankton Samples Collected from the Sacramento River and Yolo Bypass, California, 2017-2020 Zooplankton samples were collected at a site in the Yolo Bypass in Northern California and at a comparison site on the Sacramento River below the city of Sacramento and analyzed for a large suite of current-use pesticides and degradates. Samples were collected biweekly in the summer/fall 2017 and 2018, and from May 2019−March 2020. Samples were collected by towing a 150-micron conical plankton net for 5 minutes by boat at each site. In the laboratory, zooplankton samples were filtered through a 63-micrometer sieve to separate the zooplankton and vegetation/detritus from the water. Large sticks, twigs, rocks, and leaves were rinsed with organic free water into the sieve and then discarded. The remaining mass in the... Categories: Data; Tags: California, Environmental Health, Hydrology, Sacramento, USGS Science Data Catalog (SDC), All tags... Water Quality, Zooplankton, environment, pesticide and herbicide contamination, Fewer tags Herbicide Safener and Co-Applied Herbicide Concentrations for Seven Streams across Iowa and Illinois (March 2016 to June 2017) Four dichloroacetamide herbicide safeners (AD-67, benoxacor, dichlormid, and furilazole) and two co-applied herbicides (acetochlor and metolachlor) were measured in water samples from 7 streams across Iowa and Illinois. Iowa water samples were collected from March 2016 to June 2017, and Illinois water samples were collected from September 2016 to June 2017. The compounds studied are applied to corn, and Iowa and Illinois are the two largest corn producing states in the U.S. The seven stream sites are all adjacent to agricultural fields in corn production. Water samples (1-L) were collected in amber glass bottles using a grab or depth weighted approach. With the exception of one site, Iowa River at Wapello (USGS... Categories: Data; Tags: Corn Belt region, Environmental Health, Illinois, Iowa, USGS Science Data Catalog (SDC), All tags... United States, Water Quality, contaminant transport, ecotoxicity, herbicide, herbicide safeners, stormwater, stream discharge, water quality, Fewer tags Pesticide Concentrations in American Bullfrog (Lithobates catesbeianus) Tadpoles Collected from Ponds and Reservoirs near Mead, Nebraska To evaluate the potential uptake and accumulation of pesticides in amphibians, American bullfrog (Lithobates catesbeianus) tadpoles were collected from surface water sites (four ponds and one reservoir) in 2021 near Mead, Nebraska. Sites were located in the landscape surrounding the AltEn ethanol plant, a plant which had previously received pesticide treated (coated) seeds. Tadpoles were collected in November 2021, these tadpoles hatched in June 2021. The tadpole tissues were dried, homogenized, and then extracted using acetonitrile at 100 °C. Samples were analyzed for 166 pesticides and degradates using both gas and liquid chromatography-tandem mass spectrometry. Overall, 14 pesticides and degradates were detected... Categories: Data; Tags: Amphibians, Degradates, Ecology, Environmental Health, Gas Chromatography, All tags... Liquid Chromatography, Mass Spectrometry, Mead Nebraska, Pesticides, Surface Water, USGS Science Data Catalog (SDC), Water Quality, biota, Fewer tags Concentrations of pesticides in silicone bands as passive samplers and sediment in Pinnacles National Park and Bureau of Land Management lands in San Benito County, California, 2019-2021 To better understand the potential pesticide exposure, samples were collected from locations along two creeks in Pinnacles National Park and four creeks in nearby Bureau of Land Management (BLM) lands. Silicone bands were used as passive sampling devices (PSD) staked in the creek and above in the air (above the water line). Sampling was conducted in the summer from 2019 to 2021. PSDs were deployed for 2 to 4 weeks and sediment was collected once in 2020. PSDs were extracted via sonication with an organic solvent and sediment was extracted via pressurized liquid extraction and solid phase extraction cleanup. Samples were analyzed for 168 pesticides and degradates using both gas and liquid chromatography-tandem mass... Categories: Data; Tags: Arroyo Leona, Bear Creek, California, Chalone Creek, Clear Creek, All tags... Degradates, Gas Chromatography, Laguna Creek, Liquid Chromatography, Mass Spectrometry, Passive Sampling Device, Pesticides, Pinnacles National Park, Silicone Bands, Surface Water, USGS Science Data Catalog (SDC), White Creek, biota, none, Fewer tags Concentrations of pesticides in multiple matrices to measure exposure of wild bees visiting pollinator hedgerows in northern California To better understand the exposure of wild bees to pesticides in an agricultural landscape, samples were collected from fields in northern California. Hedgerows are known to provide habitat for wild bees, but these bees may also be exposed to pesticides from nearby agricultural fields. The study included eight hedgerow sites located in an intensively managed agricultural landscape that includes almonds, (wine) grapes, rice, tomatoes, and walnuts. In addition to collecting both wild bees and honey bees, soil, flowers, and silicone passive sampling devices (PSD; staked near the hedgerows to sample the air) were also included. Sampling was conducted from April to June 2016, to coincide with peak bloom and bee activity... Categories: Data; Tags: California, environment, fungicides, herbicides, insecticides, All tags... non-Apis pollinators, pesticide and herbicide contamination, pesticides, pollinators, pollinators, Fewer tags A Multiresidue Method for the Analysis of Pesticides in Water using Solid-Phase Extraction with Gas and Liquid Chromatography-Tandem Mass Spectrometry (ver. 2.0, April 2023) Applications of pesticides in agricultural and urban settings play an essential role in increasing crop yields, preserving food and materials, reducing pest-borne diseases, and eradicating or deterring pests. Pesticides are transported from their point of application to environmental media, including surface water. To better understand the fate of fate and transport of pesticides in the environment, analytical methods are necessary to measure pesticides in waters. Herein, a method is described for the extraction and analysis of pesticides and pesticide degradates in filtered surface water and paired suspended sediment samples. Water samples (~ 1 L) are filtered using 0.7 μm glass-fiber filters prior to being extracted... Categories: Data; Tags: USGS Science Data Catalog (SDC), environment, gas chromatography, liquid chromatography, mass spectroscopy, All tags... pesticide and herbicide contamination, pesticides, water quality, Fewer tags Absorption, distribution, metabolism, and elimination of seed-treatment pesticides following the dosing of Japanese quail (Coturnix japonica) Japanese quail (Coturnix japonica) were orally dosed with pesticide-treated or control-untreated wheat seeds. Pesticide treated wheat seeds were analytically verified for active ingredients of imidacloprid, metalaxyl, tebuconazole, and fludioxonil. Pesticide and metabolite residues were measured in plasma, liver, brain, kidney, muscle, and excreta of exposed and control birds. Samples were extracted via solid phase extraction, pressurized liquid extraction, or sonication. Clean-up steps included protein precipitation followed by solid phase extraction. All samples were analyzed by liquid chromatography tandem mass spectrometry. Categories: Data; Tags: Coturnix japonica, Environmental Health, USGS Science Data Catalog (SDC), United States, environment, All tags... fungicides, high performance liquid chromatography, mass spectrometry, metabolites, neonicotinoid insecticides, pesticide residues, pharmacokinetics, seed dressings, Fewer tags Fungicides in nectar and pollen collected by bumble bees in a cherry orchard Lab-reared colonies of Bombus huntii (Hunt bumble bee) were deployed in a commercial cherry orchard in the spring of 2016. A fungicide formulation containing boscalid (25.2%) and pyraclostrobin (12.8%) was applied one time at the recommended label rate. Nectar and pollen were collected daily, beginning two days before spray application and continuing for ten days following. Nectar samples were extracted with acetonitrile and cleaned up using dispersive solid-phase extraction with primary-secondary amine, C18, and magnesium sulfate. Pollen samples were extracted with ethyl acetate. Both types of samples were analyzed by GC-MS/MS for boscalid and pyraclostrobin. Fungicide concentrations in nectar varied spatially... Categories: Data; Tags: Bombus, Ecology, Environmental Health, Oregon, USGS Science Data Catalog (SDC), All tags... United States, agriculture, agrochemicals, ecotoxicology, fungicides, pesticide and herbicide contamination, pesticides, Fewer tags 1 2 »