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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,...
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,
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,
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;...
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...
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,
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,
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...
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),
Zooplankton samples were collected in the summer/fall of 2022 and 2023 at multiple sites in the Sacramento River, Yolo Bypass, and Cache Slough Region of California and analyzed for a suite of 160 current-use pesticides and pesticide degradates by the U.S. Geological Survey Organic Chemistry Research Laboratory. In 2022 samples were collected at two sites in the Bypass and at a comparison site on the Sacramento River from early August to mid-October. In 2023 zooplankton samples were collected at one site upstream of the Yolo Bypass in Northern California, four sites within the Bypass, one site downstream of the Bypass in the Cache Slough region, and at a comparison site on the Sacramento River from late July through...
Categories: Data;
Tags: California,
Environmental Health,
Sacramento,
USGS Science Data Catalog (SDC),
Water Quality,
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),
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...
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...
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...
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,
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),
To determine aqueous pyrethroid partitioning across a salinity gradient 20 mL Pyrex beakers were filled with 8 mL of deionized water at varying salinities (0, 0.5, 2, 6 ppt). Salinity was adjusted using a 10 ppt stock solution (made by diluting Instant Ocean into deionized water). The water samples were spiked with pyrethroids (bifenthrin, cyhalothrin, cyfluthrin, cypermethrin, deltamethrin, esfenvalerate, fenpropathrin) at 500 ng/L (pyrethroid stock solution was 0.25 ng/µL in acetone, 16 µL added to each beaker). Samples were equilibrated in the dark (beaker covered with aluminum foil and placed in a cardboard box; the first set was equilibrated for 24 hr, the second set for 120 hr). Each set of samples at a particular...
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