Filters: partyWithName: Michael S Gross (X)
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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,
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),
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,...
Chemically intensive crop production depletes wildlife food resources, hinders animal development, health, survival, and reproduction, and it suppresses wildlife immune systems, facilitating emergence of infectious diseases with excessive mortality rates. Gut microbiota is crucial for wildlife’s response to environmental stressors. Its composition and functionality are sensitive to diet changes and environmental pollution associated with modern crop production. In the study entitled Exposure to crop production alters cecal prokaryotic microbiota, inflates virulome and resistome in wild prairie grouse we use shotgun metagenomics to demonstrate that exposure to modern crop production detrimentally affects cecal...
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...
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,
In the United States and globally, the lack of data on contaminant exposure from unregulated private-well point-of-use (POU) tapwater (TW) is a recognized public health data gap and an obstacle to risk management and homeowner decision making. Mead, Nebraska, is an agricultural community about 30 miles west of Omaha. To help address the lack of data on broad contaminant exposures in TW sourced from private water wells, a total of 22 samples were collected from 18 private wells during June 2022 and January 2023 and analyzed for 495 organic compounds, 34 inorganic constituents, and 11 microbial groups. The organic compounds included pesticides, pharmaceuticals, volatile organic compounds (VOCs), disinfection byproducts...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Environmental Health,
Nebraska,
USGS Science Data Catalog (SDC),
Water Quality,
biota,
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,
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,
- Observations of test subjects, - Body weight, organ/tissue weights - Biomarker data (oxidative DNA damage, thyroid hormones, corticosterone, gene expression) in various tissues - Residues as percent of administered dose - Tissues to plasma rations - Metabolites and ratios - Elimination half-lives
Pesticides are widely applied and can enter the environment, potentially effecting non-target organisms. To better evaluate pesticide exposure using non-lethal techniques, a method was developed for the extraction of pesticides and their degradates from small (100 µL) volume plasma samples. Solid phase extraction was used for lipid removal after plasma samples were protein precipitated. Samples were analyzed with liquid chromatography and gas chromatography with tandem mass spectrometry. Samples were spiked at three different concentrations, low (25 ng/mL), medium (100 ng/mL), and high (250 ng/mL) and recoveries of 70 to 130% were achieved across all spike levels for 179, 180, and 183 of 210 target compounds were...
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