This dataset includes pesticide-concentration results for 32 discrete water samples that were collected on the islands of Kauai and Oahu between November 21, 2016 and April 29, 2017. The water samples were collected for the Pesticide-Monitoring Program of Surface Water in the State of Hawaii. This dataset consists of five files: a summary file, a sample-list file, two results files, and this metadata file. The summary file (Summary_of_pesticide_results_for_discrete_samples_Hawaii_Nov2016_Apr2017.pdf) includes maps and a table of the sample sites, graphs that summarize the most frequently detected pesticide compounds in the water samples, and tables that summarize comparisons between (1) concentrations of detected pesticide compounds and (2) water-quality standards, criteria, and benchmarks. The sample-list file [List_of_discrete_samples_Hawaii_Nov2016_Apr2017.csv] contains a list of 32 samples and attributes that describe where, when, and how each sample was collected. The first results file [All_pesticide_results_(ngL)_for_discrete_samples_Hawaii_Nov2016_Apr2017.csv] contains all pesticide-concentration results (in nanograms per liter) for all 32 samples, and these results were obtained from the U.S. Geological Survey (USGS) National Water Information System (NWIS) database (https://doi.org/10.5066/F7P55KJN). The second results file [Pesticide_results_(ngL)_for_detections_only_in_discrete_samples_Hawaii_Nov2016_Apr2017.csv] is a subset of the first results file, and contains pesticides-concentration results for pesticide-compound detections only. For context, both results files include, for each pesticide result, the maximum contaminant level in drinking water, the lowest human-health benchmark considered, and the lowest aquatic-life benchmark considered, if available. This dataset contains summaries and results that were derived from data retrieved from NWIS on January 18, 2018. The data that were retrieved from NWIS are subject to revision, so users should check NWIS (https://doi.org/10.5066/F7P55KJN) for the most current verion of the data.

This dataset contains pesticide-concentration values and other information for water samples and quality-control samples collected at surface-water sites on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi between November 2016 and June 2019. The water water samples and quality-control samples were collected for a study that assessed pesticides in surface water in Hawaiʻi, as described in a U.S. Geological Survey (USGS) report available at https://doi.org/10.3133/sir20245071. The USGS National Water Quality Laboratory analyzed the water samples for pesticides that consisted of active ingredients in pesticide products and degradates of active ingredients in pesticide products. This dataset has three comma-separated value (csv) files. The first csv file (1_water_samples.csv) contains information for the water samples and quality-control samples. The second csv file (2_pesticide_concentrations_WS.csv) contains pesticide-concentration values for the water samples and also contains water-quality standards and benchmarks established by the USGS, the U.S. Environmental Protection Agency, and the State of Hawaiʻi. The third csv file (3_pesticide_concentrations_QC.csv) contains pesticide-concentration values and other information for quality-control samples. Concentration values in the second file were retrieved from the USGS National Water Information System (https://doi.org/10.5066/F7P55KJN) and are subject to revision. Users can access the concentration values at https://doi.org/10.5066/F7P55KJN and at The Water-Quality Portal (https://doi.org/10.5066/P9QRKUVJ). Information for the sample sites is available at https://doi.org/10.5066/P95XY6ZY and https://doi.org/10.5066/F7P55KJN.

This dataset contains pesticide-concentration values and other information for water samples and quality-control samples collected at surface-water sites on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi between November 2016 and June 2019. The water water samples and quality-control samples were collected for a study that assessed pesticides in surface water in Hawaiʻi, as described in a U.S. Geological Survey (USGS) report available at https://doi.org/10.3133/sir20245071. The USGS National Water Quality Laboratory analyzed the water samples for pesticides that consisted of active ingredients in pesticide products and degradates of active ingredients in pesticide products. This dataset has three comma-separated value (csv) files. The first csv file (1_water_samples.csv) contains information for the water samples and quality-control samples. The second csv file (2_pesticide_concentrations_WS.csv) contains pesticide-concentration values for the water samples and also contains water-quality standards and benchmarks established by the USGS, the U.S. Environmental Protection Agency, and the State of Hawaiʻi. The third csv file (3_pesticide_concentrations_QC.csv) contains pesticide-concentration values and other information for quality-control samples. Concentration values in the second file were retrieved from the USGS National Water Information System (https://doi.org/10.5066/F7P55KJN) and are subject to revision. Users can access the concentration values at https://doi.org/10.5066/F7P55KJN and at The Water-Quality Portal (https://doi.org/10.5066/P9QRKUVJ). Information for the sample sites is available at https://doi.org/10.5066/P95XY6ZY and https://doi.org/10.5066/F7P55KJN.

This dataset includes information for the sample sites described in the U.S. Geological Survey (USGS) Scientific-Investigations Report 2024-5071, available at https://doi.org/10.3133/sir20245071. The sample sites were at surface-water bodies on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi. Site information is provided in a comma-separated-value (csv) file and a shapefile. The shapefile contains the same information as the csv file but is formatted for use in a geospatial information system.

This dataset includes information for the sample sites described in the U.S. Geological Survey (USGS) Scientific-Investigations Report 2024-5071, available at https://doi.org/10.3133/sir20245071. The sample sites were at surface-water bodies on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi. Site information is provided in a comma-separated-value (csv) file and a shapefile. The shapefile contains the same information as the csv file but is formatted for use in a geospatial information system.

The U.S. Geological Survey (USGS) deployed passive samplers at surface-water and groundwater sites on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi for several weeks each during 2015–19. The passive samplers were deployed to assess the occurrence of pesticides and pesticide degradates, herein referred to as pesticides, in water at the sites. Some of the passive samplers were also used to assess the occurrence of additional organic contaminants and wastewater indicators in water at the sites. This dataset includes files with chemical results for the passive samplers. The chemical results include masses of pesticides that accumulated in the passive samplers and concentration values that represent the average concentrations of chemicals in water during the deployment of a passive sampler at a site. The data release includes five files. The first file (1_passive-sampler_sites.csv) contains information for each passive sampler that was deployed in water. The second file (2_pesticide_masses_POCIS.csv) contains mass values of pesticides that accumulated in polar-organic-chemical-integrative sampler (POCIS) units of passive samplers. The third file (3_pesticide_concentrations_POCIS.csv) contains concentration values of selected pesticides that accumulated in POCIS units of passive samplers. The fourth file (4_organic_contaminants_SPMD.csv) contains concentration values for organic contaminants that accumulated in semipermeable-membrane-device (SPMD) units of passive samplers. The organic contaminants include organochlorine pesticides, polybrominated diphenyl ether residues, total polychlorinated biphenyl residues, and polycyclic aromatic hydrocarbon residues. The fifth file (5_wastewater_indicators_POCIS.csv) contains results for pharmaceutical compounds and organic waste compounds that accumulated in the POCIS units of the passive samplers. The third file includes water-quality standards and benchmarks established by the State of Hawaiʻi, the U.S. Environmental Protection Agency, and USGS. The USGS National Water Quality Laboratory (NWQL) determined the occurrence of pesticides and pharmaceutical compounds in POCIS units of passive samplers. The USGS Columbia Environmental Research Center (CERC) determined the occurrence of organic contaminants in SPMD units of passive samplers and determined the occurrence of organic waste compounds in POCIS units of the passive samplers.

The U.S. Geological Survey (USGS) deployed passive samplers at surface-water and groundwater sites on the Hawaiian Islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi for several weeks each during 2015–19. The passive samplers were deployed to assess the occurrence of pesticides and pesticide degradates, herein referred to as pesticides, in water at the sites. Some of the passive samplers were also used to assess the occurrence of additional organic contaminants and wastewater indicators in water at the sites. This dataset includes files with chemical results for the passive samplers. The chemical results include masses of pesticides that accumulated in the passive samplers and concentration values that represent the average concentrations of chemicals in water during the deployment of a passive sampler at a site. The data release includes five files. The first file (1_passive-sampler_sites.csv) contains information for each passive sampler that was deployed in water. The second file (2_pesticide_masses_POCIS.csv) contains mass values of pesticides that accumulated in polar-organic-chemical-integrative sampler (POCIS) units of passive samplers. The third file (3_pesticide_concentrations_POCIS.csv) contains concentration values of selected pesticides that accumulated in POCIS units of passive samplers. The fourth file (4_organic_contaminants_SPMD.csv) contains concentration values for organic contaminants that accumulated in semipermeable-membrane-device (SPMD) units of passive samplers. The organic contaminants include organochlorine pesticides, polybrominated diphenyl ether residues, total polychlorinated biphenyl residues, and polycyclic aromatic hydrocarbon residues. The fifth file (5_wastewater_indicators_POCIS.csv) contains results for pharmaceutical compounds and organic waste compounds that accumulated in the POCIS units of the passive samplers. The third file includes water-quality standards and benchmarks established by the State of Hawaiʻi, the U.S. Environmental Protection Agency, and USGS. The USGS National Water Quality Laboratory (NWQL) determined the occurrence of pesticides and pharmaceutical compounds in POCIS units of passive samplers. The USGS Columbia Environmental Research Center (CERC) determined the occurrence of organic contaminants in SPMD units of passive samplers and determined the occurrence of organic waste compounds in POCIS units of the passive samplers.

Dissolved pesticides were measured in weekly water samples from 85 wadeable streams in Central Coastal California over a variable six-week period during March–May, 2017, as part of the California Stream Quality Assessment (CSQA) study conducted by the U.S. Geological Survey's (USGS) Regional Stream-Quality Assessment (RSQA) Project. The 85 streams consisted of 40 urban sites (5–100% urban land in the lower basin), 9 agricultural sites, 24 mixed land-use sites, and 12 undeveloped sites. Water samples were filtered (0.7 micrometers) and analyzed for 253 pesticide compounds by direct-injection liquid chromatography with tandem mass-spectrometry (LC-MS/MS). Two similar LC-MS/MS methods were used: a broad-spectrum (223 compounds) method in use since 2012 and a newly developed method for 30 new-generation fungicides and diamide and neonicotinoid insecticides. This Data Release provides sampling-site locations, analyte information, concentration data for pesticide compounds in environmental weekly water samples, quality-control data for the new method (to supplement previously published quality control data for the standard method), aquatic-life benchmark and Pesticide Toxicity Index toxicity concentration values that were used to assess potential toxicity, estimates of agricultural and nonagricultural pesticide-use data, and streamflow data for gaged sites, in support of the journal article, “New-generation pesticides are prevalent in California’s Central Coast streams,” by Sandstrom, M.W., Nowell, L.H., Mahler, B.J., and Van Metre, P.C.

Dissolved pesticides were measured in weekly water samples from 85 wadeable streams in Central Coastal California over a variable six-week period during March–May, 2017, as part of the California Stream Quality Assessment (CSQA) study conducted by the U.S. Geological Survey's (USGS) Regional Stream-Quality Assessment (RSQA) Project. The 85 streams consisted of 40 urban sites (5–100% urban land in the lower basin), 9 agricultural sites, 24 mixed land-use sites, and 12 undeveloped sites. Water samples were filtered (0.7 micrometers) and analyzed for 253 pesticide compounds by direct-injection liquid chromatography with tandem mass-spectrometry (LC-MS/MS). Two similar LC-MS/MS methods were used: a broad-spectrum (223 compounds) method in use since 2012 and a newly developed method for 30 new-generation fungicides and diamide and neonicotinoid insecticides. This Data Release provides sampling-site locations, analyte information, concentration data for pesticide compounds in environmental weekly water samples, quality-control data for the new method (to supplement previously published quality control data for the standard method), aquatic-life benchmark and Pesticide Toxicity Index toxicity concentration values that were used to assess potential toxicity, estimates of agricultural and nonagricultural pesticide-use data, and streamflow data for gaged sites, in support of the journal article, “New-generation pesticides are prevalent in California’s Central Coast streams,” by Sandstrom, M.W., Nowell, L.H., Mahler, B.J., and Van Metre, P.C.

A novel U.S. Geological Survey-developed active water sampler was deployed at Ulatis Creek in Solano County, California for 24 hours from November 15, 2023 to November 16, 2023. Discrete surface water samples were collected at the start and end points of the active water sampler deployment interval for comparison to the active water sampler. Samples from the active water sampler and the discrete surface water samples were analyzed for 183 pesticides dissolved in water and 178 pesticides in suspended sediment at the U.S. Geological Survey Organic Chemistry Research Laboratory in Sacramento, California. Twenty-seven out of 183 pesticide compounds measured in sample extracts were detected in at least one of the grab sample or active sampler dissolved water extracts with concentrations ranging from 0.9 nanograms per liter to 32.2 nanograms per liter. No pesticides were detected in the suspended sediment filtered from the water.