SEARCH · Geology Reports

Results for “Environment and Health”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources

USGS2023

Statewide sampling to determine spatial distribution, prevalence, and occurrence of per- and polyfluoroalkyl substances (PFAS) in Illinois community water supplies, 2020–21

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals that have been manufactured and used globally since the 1940s. PFAS are used for their oil- and water-repellent properties, ability to reduce friction, and their flame-retardant nature. PFAS are widely used in a variety of products, including clothing, carpet, food packaging, and firefighting foam. The properties that make them useful in manufacturing, however, also make them persistent and mobile, causing potential exposures to the environment and humans. Known as “forever chemicals,” these compounds resist degradation and have been determined to bioaccumulate in humans and wildlife. The Illinois Environmental Protection Agency (IEPA) collected a total of 1,711 samples (includes quality-control samples) of finished water at 1,428 entry points from 1,017 Illinois community water supply (CWS) systems and analyzed the water samples for PFAS. The results following confirmation samples indicated a mean of 99 percent of all sample results were below the minimum reporting level (MRL) of 2 nanograms per liter (ng/L). Of the detections at or above the MRL, 7 of 18 PFAS were detected in 149 of 1,428 entry points (about 10 percent). Of the nearly 7.4 million residents directly served by the CWS systems sampled, more than 1.3 million residents (about 18 percent) are served by CWS systems that had at least one detection of PFAS above the MRL of 2 ng/L. The most frequently detected PFAS were perfluorobutanesulfonic acid (about 6.2 percent, 37 ng/L maximum concentration), perfluorooctanesulfonic acid (PFOS) (about 5.0 percent, 150 ng/L maximum concentration), and perfluorooctanoic acid (PFOA) (about 4.8 percent, 25 ng/L maximum concentration). Of the 1,428 entry point samples from the CWS systems, 149 samples had confirmed detections of PFAS, with 93 of those 149 (about 62 percent) samples having at least one PFAS with a concentration that exceeded the median detected concentration of 3.2 ng/L. The highest concentrations detected were 150 ng/L (PFOS) and 140 ng/L (perfluorohexanesulfonic acid) at one CWS location which has been shut down and a different source of water has been provided to the consumers. Although PFAS detections were more common in CWS systems using surface-water sources (about 35 percent, 30 of 85) and mixed sources (50 percent, 5 of 10) compared to those using groundwater sources (about 9 percent, 114 of 1,333), a greater range of PFAS concentrations were observed in groundwater CWS systems (2 to 150 ng/L) than in surface-water CWS systems (2 to 15 ng/L). Statistically significant differences were determined between some detected PFAS (PFOA, PFOS, and perfluorohexanoic acid) and the source of drinking water (groundwater, surface water, or mixed). This report summarizes the occurrence and spatial distribution of PFAS in CWS systems across Illinois. The results from this sampling effort could be used by Illinois public health officials to identify the potential risk of PFAS in drinking water to human health.

Illinois↗

USGS2011

Removal of inorganic mercury and methylmercury from surface waters following coagulation of dissolved organic matter with metal-based salts

The presence of inorganic mercury (IHg) and methylmercury (MeHg) in surface waters is a health concern worldwide. This study assessed the removal potential use of metal-based coagulants as a means to remove both dissolved IHg and MeHg from natural waters and provides information regarding the importance of Hg associations with the dissolved organic matter (DOM) fraction and metal hydroxides. Previous research indicated coagulants were not effective at removing Hg from solution; however these studies used high concentrations of Hg and did not reflect naturally occurring concentrations of Hg. In this study, water collected from an agricultural drain in the Sacramento-San Joaquin Delta was filtered to isolate the dissolved organic matter (DOM) fraction. The DOM was then treated with a range of coagulant doses to determine the efficacy of removing all forms of Hg from solution. Three industrial-grade coagulants were tested: ferric chloride, ferric sulfate, and polyaluminum chloride. Coagulation removed up to 85% of DOM from solution. In the absence of DOM, all three coagulants released IHg into solution, however in the presence of DOM the coagulants removed up to 97% of IHg and 80% of MeHg. Results suggest that the removal of Hg is mediated by DOM-coagulant interactions. There was a preferential association of IHg with the more aromatic, higher molecular weight fraction of DOM but no such relationship was found for MeHg. This study offers new fundamental insights regarding large-scale removal of Hg at environmentally relevant regarding large-scale removal of Hg at environmentally relevant concentrations.

Science of the Total Environment↗

USGS2010

Land-Use Portfolio Modeler, Version 1.0

Natural hazards pose significant threats to the public safety and economic health of many communities throughout the world. Community leaders and decision-makers continually face the challenges of planning and allocating limited resources to invest in protecting their communities against catastrophic losses from natural-hazard events. Public efforts to assess community vulnerability and encourage loss-reduction measures through mitigation often focused on either aggregating site-specific estimates or adopting standards based upon broad assumptions about regional risks. The site-specific method usually provided the most accurate estimates, but was prohibitively expensive, whereas regional risk assessments were often too general to be of practical use. Policy makers lacked a systematic and quantitative method for conducting a regional-scale risk assessment of natural hazards. In response, Bernknopf and others developed the portfolio model, an intermediate-scale approach to assessing natural-hazard risks and mitigation policy alternatives. The basis for the portfolio-model approach was inspired by financial portfolio theory, which prescribes a method of optimizing return on investment while reducing risk by diversifying investments in different security types. In this context, a security type represents a unique combination of features and hazard-risk level, while financial return is defined as the reduction in losses resulting from an investment in mitigation of chosen securities. Features are selected for mitigation and are modeled like investment portfolios. Earth-science and economic data for the features are combined and processed in order to analyze each of the portfolios, which are then used to evaluate the benefits of mitigating the risk in selected locations. Ultimately, the decision maker seeks to choose a portfolio representing a mitigation policy that maximizes the expected return-on-investment, while minimizing the uncertainty associated with that return-on-investment. The portfolio model, now known as the Land-Use Portfolio Model (LUPM), provided the framework for the development of the Land-Use Portfolio Modeler, Version 1.0 software (LUPM v1.0). The software provides a geographic information system (GIS)-based modeling tool for evaluating alternative risk-reduction mitigation strategies for specific natural-hazard events. The modeler uses information about a specific natural-hazard event and the features exposed to that event within the targeted study region to derive a measure of a given mitigation strategy`s effectiveness. Harnessing the spatial capabilities of a GIS enables the tool to provide a rich, interactive mapping environment in which users can create, analyze, visualize, and compare different

Techniques and Methods↗

USGS2021

Satellites for long-term monitoring of inland U.S. lakes: The MERIS time series and application for chlorophyll-a

Lakes and other surface fresh waterbodies provide drinking water, recreational and economic opportunities, food, and other critical support for humans, aquatic life, and ecosystem health. Lakes are also productive ecosystems that provide habitats and influence global cycles. Chlorophyll concentration provides a common metric of water quality, and is frequently used as a proxy for lake trophic state. Here, we document the generation and distribution of the complete MEdium Resolution Imaging Spectrometer (MERIS; Appendix A provides a complete list of abbreviations) radiometric time series for over 2300 satellite resolvable inland bodies of water across the contiguous United States (CONUS) and more than 5,000 in Alaska. This contribution greatly increases the ease of use of satellite remote sensing data for inland water quality monitoring, as well as highlights new horizons in inland water remote sensing algorithm development. We evaluate the performance of satellite remote sensing Cyanobacteria Index (CI)-based chlorophyll algorithms, the retrievals for which provide surrogate estimates of phytoplankton concentrations in cyanobacteria dominated lakes. Our analysis quantifies the algorithms' abilities to assess lake trophic state across the CONUS. As a case study, we apply a bootstrapping approach to derive a new CI-to-chlorophyll relationship, ChlBS, which performs relatively well with a multiplicative bias of 1.11 (11%) and mean absolute error of 1.60 (60%). While the primary contribution of this work is the distribution of the MERIS radiometric timeseries, we provide this case study as a roadmap for future stakeholders' algorithm development activities, as well as a tool to assess the strengths and weaknesses of applying a single algorithm across CONUS.

Alaska, Minnesota↗

USGS2025

Global recreational consumption of non-native inland fish: Higher economic benefits, but lower nutritional value and climate resilience

Inland recreational fisheries are globally significant leisure pursuits, with well-documented benefits to human health and well-being, but also one of the principal drivers of non-native fish introductions to enhance fishing opportunities, whether for sport or sustenance. In this study, we assess the relative reliance of global inland recreational fisheries on non-native versus native species for harvest. We further examine how this reliance varies by economic and nutritional value as well as the climate vulnerability of the species involved. We demonstrate that, of the 1,325,851 t of inland recreational fishes recreationally harvested for consumption worldwide in 2021, non-native fish were a small proportion (4 %; 53,651 t). On a global scale, non-native fish contributed a net positive 38.2 % economic value to inland recreational harvest. However, they also contributed a net negative −21.9 % nutritional value to inland recreational harvest. Non-native fishes were also more climate vulnerable (i.e., higher average climate vulnerability index values) and thus proportionally increased overall estimates of climate vulnerability with a net positive of 70.9 %. Our results quantitatively demonstrate that non-native species play a more important role in inland consumptive recreational fisheries than their mere harvest volume would suggest. However, many nuances were seen on the continent and country scale, which reflect the complexity of fisher behavior, fish distribution and socio-economic factors. Our findings help unravel the complex effects of non-native species on human activities and underscore the need to evaluate their global impacts holistically.

Science of the Total Environment↗

USGS2026

Toxicity of synergized permethrin residues in cattle dung to two temperate dung beetle species after application of common livestock pour-on treatment

Essential to pasture health, dung beetles (Coleoptera: Scarabaeidae) provide key ecosystem services across natural and managed rangeland habitats. Insecticide residues in livestock dung can negatively impact dung beetle populations, and synergized pyrethroid products are commonly used to combat resistant pest fly populations. Here, permethrin residues were measured by GC-MS/MS in fresh cattle feces on Days −2 (pretreatment), 4, 8, 16, and 30 after the label rate application of a formulated pour-on treatment (a.i. 5% permethrin, 5% piperonyl butoxide [PBO]). Mean (± SE) measured permethrin concentrations were the highest on Day 4 at 1400 ± 360 ng of permethrin/g of dung (dry weight) with a maximum concentration of 2200 ng/g. Approximately, 99% of applied permethrin was excreted by Day 16, with no detection by Day 30. Field-collected dung was used in a 48-hour toxicity test and with three treatment groups (control [Day −2], low risk [Day 16], and high risk [Day 4]). Two temperate dung beetle species were tested: Onthophagus pennsylvanicus Harold and Canthon chalcites Haldeman. Mean (± SE) mortality of O. pennsylvanicus was 28 ± 5% and 58 ± 13% for low and high risk treatments, respectively. Mean (± SE) mortality of C. chalcites was lower than O. pennsylvanicus with 10 ± 4% and 40 ± 10% for low and high risk treatments, respectively. PBO was detected on Days 4 and 8, and the permethrin:PBO ratio was 10:1 on Day 4, i.e., high risk treatment. Data presented highlight episodic risks of pour-on products and support threshold-based, integrated pest management approaches.

Oklahoma↗

USGS2022

Long-term impacts of impervious surface cover change and roadway deicing agent application on chloride concentrations in exurban and suburban watersheds

Roadway deicing agents, including rock salt and brine containing NaCl, have had a profound impact on the water quality and aquatic health of rivers and streams in urbanized areas with temperate climates. Yet, few studies evaluate impacts to watersheds characterized by relatively low impervious surface cover (ISC; < 15 %). Here, we use long-term (1997-2019), monthly streamwater quality data combined with daily streamflow for six exurban and suburban watersheds in southeastern Pennsylvania to examine the relations among chloride (Cl − ) concentrations and ISC. Both flow-normalized Cl − concentrations and ISC increased over time in each of the six watersheds, consistent with changes in watershed management (e.g., ISC, road salt application, etc.). The watersheds that experienced the greatest changes in percent ISC (e.g., agriculture replaced by residential and commercial development) experienced the greatest changes in flow-normalized Cl − concentrations. We also utilized a comprehensive mass-balance model (2011–2018) that indicated Cl − inputs exceeded the outputs for the study watersheds. Road salt applied to state roads, non-state roads, and other impervious surfaces accounted for the majority of Cl − inputs to the six watersheds. Furthermore, increasing Cl − concentrations during baseflow conditions confirm impacts to shallow groundwater. Although flow-normalized Cl − concentrations are below the U.S. Environmental Protection Agency's chronic threshold value for impacts to aquatic organisms, year-round exceedances may result before the end of this century based on current trends. Though reduced Cl − loading to streams may be achieved by limiting the expansion of impervious surfaces in exurban and suburban watersheds, changes in baseflow concentrations are likely to be gradual because of the accumulated Cl − in groundwater.

Pennsylvania↗

USGS2024

Elemental composition and potential toxicity of the riverine macrophyte Podostemum ceratophyllum Michx. reflects land use in eastern North America

Land use influences surface water quality, often alleviating stoichiometric constraints on primary production and altering biogeochemical cycling. However, land use effects on nutrient content and potential trace metal accumulation in aquatic plants remain unclear, and high concentrations of metals and altered nutrient ratios could impact the health of herbivores and detritivores. We tested for land use effects on nutrient and trace metal accumulation in a widespread riverine macrophyte, Podostemum ceratophyllum , collected from 91 locations from Georgia to Maine, USA in 2014–2016. We quantified carbon (C), nitrogen (N), phosphorus (P), their molar and mass ratios, N and C stable isotopes, and 17 additional elements in dried plants collected from each location to estimate relationships between plant tissue content and watershed land use, which we quantified as agriculture, forest, and development. Decreasing forest cover was correlated with increasing δ 15 N, Mg, Mn, and P in Podostemum tissue. Increasing urban development was correlated with increasing δ 15 N, Mg and P, while increasing agriculture was correlated with a decrease in C: P and the concentrations of multiple metals, along with increases in P, Mg and δ 15 N. Decreases in ratios of N: P and C:P with increasing agriculture and urban development in the watershed indicate more rapid P storage relative to C and N in plant tissue, and increased resource quality of the plant to consumers in these watersheds. We also observed potentially toxic dietary concentrations of some trace metals (B, Cd, Tl, Zn) in plant tissue which could be related to the plant's natural herbivory defense system or to land use. We conclude that land use influences the elemental composition of P. ceratophyllum , and potentially the quality and toxicity of the plant to herbivores and detritivores in eastern North American rivers.

Science of the Total Environment↗

USGS2016

Occurrence and concentrations of selected trace elements and halogenated organic compounds in stream sediments and potential sources of polychlorinated biphenyls, Leon Creek, San Antonio, Texas, 2012–14

The Texas Department of State Health Services issued fish consumption advisories in 2003 and 2010 for Leon Creek in San Antonio, Texas, based on elevated concentrations of polychlorinated biphenyls (PCBs) in fish tissues. The U.S. Geological Survey (USGS) measured elevated PCB concentrations in stream-sediment samples collected during 2007–9 from Leon Creek at Lackland Air Force Base (now known as Joint Base San Antonio-Lackland; the sampling site at this base is hereinafter referred to as the “Joint Base site”) and sites on Leon Creek downstream from the base. This report describes the occurrence and concentrations of selected trace elements and halogenated organic compounds (pesticides, flame retardants, and PCBs) and potential sources of PCBs in stream-sediment samples collected from four sites on Leon Creek during 2012–14. In downstream order, sediment samples were collected from Leon Creek at northwest Interstate Highway 410 (Loop 410), Rodriguez Park, Morey Road, and Joint Base. The USGS periodically collected streambed-sediment samples during low flow and suspended-sediment samples during high flow. Trace element concentrations were low compared to the consensus-based sediment-quality guidelines (SQGs) for the threshold effect concentration (TEC) and probable effect concentration (PEC). Adverse effects to benthic biota are not expected at concentrations less than the TEC and are expected at concentrations greater than the PEC. No trace element concentrations were greater than the PEC in any of the samples. Trace element concentrations were greatest at the Morey Road and Joint Base sites and exceeded the TECs by 41 and 27 percent, respectively. Trace element concentrations were lowest at the Rodriguez Park and Loop 410 sites and exceeded the TECs by 18 and 14 percent, respectively. Pesticides that have been banned for several decades are commonly detected in Leon Creek stream sediments, particularly the chlordane compounds. Chlordane compounds were detected in 84 percent of the samples and at every sample collection site. The samples collected from the Rodriguez Park site had the most pesticide compounds detected. Only samples collected from the Joint Base site had dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE), or dichlorodiphenyltrichloroethane (DDT) concentrations greater than the TEC, and a few were also greater than the PEC. Flame retardants were found at every site on Leon Creek where stream sediments were collected; however, a few compounds were frequently detected in the laboratory reagent blanks so their detections in the environmental samples may not be from local sources. Consensus-based SQGs were not available for flame retardants so samples were compared to Environment Canada Federal Environmental Quality Guidelines (FEQGs). The concentrations of flame retardants generally were greater in the suspended-sediment samples than the streambed-sediment samples and greater than the FEQGs in many cases. Eighteen PCB congeners were quantified in the sediment samples collected from Leon Creek. The samples collected from the Joint Base site had the most frequent PCB congener detections. Total PCB concentrations, computed as the sum of the 18 congeners by using the Kaplan-Meier method for left-censored environmental data, were much smaller than the TEC of 59.8 micrograms per kilogram (μg/kg). When detected, the concentrations of total PCBs in the stream-sediment samples collected from Leon Creek during 2012–14 ranged from an estimated 0.2 to 8.7 μg/kg. Sediment samples collected from Leon Creek by the USGS during 2007–9 and 2012–14 at a total of eight sites following identical field and laboratory methods were evaluated to determine if potential PCB sources could be identified. Total PCB concentrations in the sediment samples collected upstream from the Joint Base site were low or nondetections; while concentrations in the samples collected on and downstream from the Joint Base site were greater. Congeners 180 and 138 constituted the greatest proportion of the PCB mixture in samples collected upstream from, on, and downstream from the Joint Base site. Upstream from the Joint Base site, congeners 180 and 138 constituted 50 percent and 35 percent respectively of the PCBs congeners found in the samples. On and downstream from the Joint Base site, congeners 180 and 138 constituted 80 percent and 13 percent respectively of the PCBs congeners found in the samples. Chi-square (C2) tests also indicate that samples collected from the Loop 410 site were statistically different from samples collected from the Joint Base site and sites downstream. The PCB congener pattern in the Leon Creek samples is most like the congener mixture in Aroclor 1260, which is chemically similar to the PCBs detected in the fish samples that resulted in the 2003 fish consumption advisory.

Texas↗

USGS2023

Synergistic soil, land use, and climate influences on wind erosion on the Colorado Plateau: Implications for management

Two decades of drought in the southwestern USA are spurring concerns about increases in wind erosion, dust emissions, and associated impacts on ecosystems, agriculture, human health, and water supply. Different avenues of investigation into primary drivers of wind erosion and dust have yielded mixed results depending on the spatial and temporal sensitivity of the evidence. We monitored passive aeolian sediment traps from 2017 to 2020 across eighty-one sites near Moab UT to understand patterns of sediment flux. At measurement sites we collated climate, soil, topography and vegetation spatial layers to better understand the context of wind erosion and then combine these data with field observations of land use in models to characterize the influence of cattle grazing, oil and gas well pads, and vehicle/heavy equipment disturbance that potentially drive both exposure of bare soil and increases in erodible sediment supply that increase vulnerability to erosion. Disturbed areas with low soil calcium carbonate content yielded high sediment transport in dry years, but notably areas with little disturbance and low bare soil exposure had much less activity. Cattle grazing had the largest land use association with erosional activity with analyses suggesting that both herbivory and trampling from cattle could be drivers. The amount and distribution of bare soil exposure from new sub-annual fractional cover remote sensing products proved very helpful in mapping erosion, and new predictive maps informed by field data are presented to help depict spatial patterns of wind erosion activity. Our results suggest that despite the magnitude of current droughts, minimizing surface disturbance in vulnerable soils can mitigate a large portion of dust emissions. Results can help managers identify eroding areas where disturbance reduction and soil surface protection measures can be prioritized.

Science of the Total Environment↗

USGS2019

Baseline environmental monitoring of groundwater, surface water, and soil at the Ammonium Perchlorate Rocket Motor Destruction Facility at the Letterkenny Army Depot, Chambersburg, Pennsylvania, 2016

Letterkenny Army Depot in Chambersburg, Pennsylvania, built an Ammonium Perchlorate Rocket Motor Destruction (ARMD) facility in 2016. The ARMD Facility was designed to centralize rocket motor destruction and contain or capture all waste during the destruction process. Ideally, there would be no contaminant transport to air, soil, or water from the facility, but the Code of Federal Regulations requires that any hazardous waste disposal facility have an environmental monitoring program in place. In a study by the U.S. Geological Survey, in cooperation with the Letterkenny Army Depot, baseline characterization of constituents in groundwater, surface water, and soil was conducted from September to December 2016 to document site conditions prior to the beginning of operations at the facility in January 2017. Groundwater wells, surface water, and soils were sampled monthly during the baseline characterization period. No sediment transport from the site occurred on days when samples were collected from surface-water sites, so no sediment was collected from the retention basin at the facility during the baseline period. Data collected during the baseline period can be compared to data collected in future years to determine whether there is any contaminant transport from the ARMD Facility to the surrounding environment. During the baseline characterization period, monthly samples were collected from 4 groundwater wells and 9 soil sites near the ARMD Facility. The only surface-water site sampled monthly during the baseline period was upgradient from the facility. There was no streamflow at surface-water sites downgradient from the facility on days when surface-water samples were collected during the baseline characterization period. Groundwater results for the four wells sampled near the ARMD Facility during the baseline period did not show any major water-quality issues. Mean specific conductance (SC) and pH in groundwater ranged from 220 to 771 microsiemens per centimeter at 25 degrees Celsius (μS/cm) and 6.45 to 6.98, respectively. No constituents in groundwater samples exceeded any U.S. Environmental Protection Agency (EPA) Maximum Contaminant Level (MCL). Dissolved iron (Fe) was the only groundwater constituent that exceeded a Secondary Maximum Contaminant Level (SMCL) established by the EPA. The SMCL for Fe is 300 micrograms per liter (μg/L); samples from three wells had mean dissolved Fe concentrations ranging from 1,100 to 2,600 μg/L. The only volatile organic compounds (VOCs) detected in groundwater samples were bromomethane, acetone, and chloromethane. All VOC detections in groundwater samples were less than the Reporting Detection Levels (RDLs). These three compounds also were detected in blank samples submitted for groundwater samples. Perchlorate was not detected in any groundwater sample collected during the baseline period. Surface-water data collected during the baseline period were strictly representative of a stream reach upgradient from the ARMD Facility. Stream discharge ranged from 0.03 to 0.08 cubic feet per second during sample collection. The mean SC and pH were 310 μS/cm and 7.6, respectively. No EPA established MCLs or SMCLs were exceeded for any constituents in samples collected from this upgradient stream. Some VOCs were detected in surface water at less than the RDLs. The VOCs detected in surface water were generally the same VOCs as those detected at less than the RDLs for groundwater. Perchlorate was detected in each sample collected from the stream; the mean concentration was 0.07 μg/L. All perchlorate results were less than the RDL of 0.2 μg/L. Soil samples collected during the baseline period did not have any constituent concentrations that exceeded any medium-specific concentrations (MSC) or soil screening levels (SSL) established by either the Commonwealth of Pennsylvania or the EPA. The Commonwealth of Pennsylvania calculates MSCs based on either a function of acceptable concentrations in groundwater or based on health concerns if the soil is directly contacted. The EPA derives acceptable concentrations of constituents (SSLs) in soil based on standardized equations combining exposure information assumptions with EPA toxicity data. The EPA calculates SSLs for residential and industrial sites. Soil sites at the ARMD Facility were considered “industrial” for comparative purposes. There was at least one order of magnitude difference between any inorganic constituent concentration detected in soil and the MSC and (or) SSL for that constituent. Four VOCs were detected in soil samples collected during the baseline period. None of the VOCs detected in the soils were within three orders of magnitude of any established MSCs or SSLs. The VOCs detected in soil were dichloromethane (also known as methylene chloride), methyl tert-butyl ether (MTBE), tetrachloroethene, and acetone (only detected once). Dichloromethane was the only VOC detected at greater than the RDLs; concentrations in all soil samples were greater than the RDLs. Dichloromethane concentrations ranged from 1.9 to 50.1 micrograms per kilogram (μg/kg). MTBE was detected in 50 percent of samples collected but all results were less than the RDLs of 1.7 to 2.6 μg/kg. Tetrachloroethene was detected in 20 percent of soil samples collected, with a maximum estimated value of 1.5 μg/kg. Inorganic constituents with the highest concentrations in soil were Fe and aluminum (Al); mean Fe and Al concentrations ranged from 28,700 to 52,400 and 10,300 to 19,800 milligrams per kilogram (mg/kg), respectively. Data collected during the baseline period in 2016 can be compared to future data to determine whether concentrations in water and soils surrounding the facility have shown any changes that could be caused by the facility operation.

Pennsylvania↗

USGS2022

Potential health effects of contaminant mixtures from point and nonpoint sources on fish and frogs in the New Jersey Pinelands

Aquatic ecosystems convey complex contaminant mixtures from anthropogenic pollution on a global scale. Point (e.g., municipal wastewater) and nonpoint sources (e.g., stormwater runoff) are both drivers of contaminant mixtures in aquatic habitats. The objectives of this study were to identify the contaminant mixtures present in surface waters impacted by both point and nonpoint sources, to determine if aquatic biota (amphibian and fish) health effects (testicular oocytes and parasites) occurred at these sites, and to understand if differences in biological and chemical measures existed between point (on-stream) and nonpoint sources (off-stream). To accomplish this, water chemistry, fishes, and frogs were collected from 21 sites in the New Jersey Pinelands, United States. Off-stream sites consisted of 3 reference and 10 degraded wetlands. On-stream sites consisted of two reference lakes and six degraded steams/lakes (four sites above and two sites below wastewater outfalls). Surface water was collected 4 times at each site and analyzed for 133 organic and inorganic contaminants. One native and five non-native fish species were collected from streams/lakes and native green frogs from wetlands (ponds and stormwater basins). Limited differences in contaminant concentrations were observed in reference and degraded wetlands but for streams/lakes, results indicated that landscape alteration, (upland agricultural and developed land) was the primary driver of contaminant concentrations rather than municipal wastewater. Incidence of estrogenic endocrine disruption (intersex) was species dependent with the highest prevalence observed in largemouth bass and black crappie and the lowest prevalence observed in green frogs and tessellated darters. Parasite prevalence was site and species dependent. Prevalence of eye parasites increased with increasing concentrations of industrial, mycotoxin, and cumulative inorganic contaminants. These findings are critical to support the conservation, protection, and management of a wide range of aquatic species in the Pinelands and elsewhere as habitat loss, alteration, and fragmentation increase with increasing development.

New Jersey↗

USGS2024

qPCR-based phytoplankton abundance and chlorophyll a: A multi-year study in twelve large freshwater rivers across the United States

Phytoplankton overgrowth, which characterizes the eutrophication or trophic status of surface water bodies, threatens ecosystems and public health. Quantitative polymerase chain reaction (qPCR) is promising for assessing the abundance and community composition of phytoplankton. However, applications of qPCR to indicate eutrophication and trophic status, especially in lotic systems, have yet to be comprehensively evaluated. For the first time, this study correlates qPCR-based phytoplankton abundance with chlorophyll a (the most widely used indicator of eutrophication and trophic status) in multiple freshwater rivers. From early summer to late fall in 2017, 2018, and 2019, we evaluated phytoplankton, chlorophyll a , pheophytin a , and the Trophic Level Index (TLI) in twelve large freshwater rivers in three regions (western, midcontinent, and eastern) in the United States. Chlorophyll a concentration had positive allometric correlations with qPCR-based phytoplankton abundance (adjusted R 2 = 0.5437, p -value < 0.001), pheophytin a concentration (adjusted R 2 = 0.3378, p -value <0.001), and TLI (adjusted R 2 = 0.4789, p -value < 0.001). Thus, a greater phytoplankton abundance suggests a higher trophic status. This work also presents the numerical values of qPCR-based phytoplankton abundance defining the boundaries among trophic statuses (e.g., oligotrophic, mesotrophic, and eutrophic) of freshwater rivers. The sampling sites in the midcontinent rivers were more eutrophic because they had significantly higher chlorophyll a concentrations, pheophytin a concentrations, and TLI values than the sites in the western and eastern rivers. The higher phytoplankton abundance at the midcontinent sites confirmed their higher trophic status. By linking qPCR-based phytoplankton abundance to chlorophyll a , this study demonstrates that qPCR is a promising avenue to investigate the population dynamics of phytoplankton and the trophic status (or eutrophication) of freshwater rivers.

Continental united States↗

USGS2015

Impact of wastewater infrastructure upgrades on the urban water cycle: Reduction in halogenated reaction byproducts following conversion from chlorine gas to ultraviolet light disinfection

The municipal wastewater treatment facility (WWTF) infrastructure of the United States is being upgraded to expand capacity and improve treatment, which provides opportunities to assess the impact of full-scale operational changes on water quality. Many WWTFs disinfect their effluent prior to discharge using chlorine gas, which reacts with natural and synthetic organic matter to form halogenated disinfection byproducts (HDBPs). Because HDBPs are ubiquitous in chlorine-disinfected drinking water and have adverse human health implications, their concentrations are regulated in potable water supplies. Less is known about the formation and occurrence of HDBPs in disinfected WWTF effluents that are discharged to surface waters and become part of the de facto wastewater reuse cycle. This study investigated HDBPs in the urban water cycle from the stream source of the chlorinated municipal tap water that comprises the WWTF inflow, to the final WWTF effluent disinfection process before discharge back to the stream. The impact of conversion from chlorine-gas to low-pressure ultraviolet light (UV) disinfection at a full-scale (68,000 m 3 d −1 design flow) WWTF on HDBP concentrations in the final effluent was assessed, as was transport and attenuation in the receiving stream. Nutrients and trace elements (boron, copper, and uranium) were used to characterize the different urban source waters, and indicated that the pre-upgrade and post-upgrade water chemistry was similar and insensitive to the disinfection process. Chlorinated tap water during the pre-upgrade and post-upgrade samplings contained 11 (mean total concentration = 2.7 μg L −1 ; n=5) and 10 HDBPs (mean total concentration = 4.5 μg L −1 ), respectively. Under chlorine-gas disinfection conditions 13 HDBPs (mean total concentration = 1.4 μg L −1 ) were detected in the WWTF effluent, whereas under UV disinfection conditions, only one HDBP was detected. The chlorinated WWTF effluent had greater relative proportions of nitrogenous, brominated, and iodinated HDBPs than the chlorinated tap water. Conversion of the WWTF to UV disinfection reduced the loading of HDBPs to the receiving stream by >90%.

Science of the Total Environment↗

USGS2019

Air pollution and respiratory hospital admissions in Shiraz, Iran, 2009 to 2015

Air pollution has been identified as one of the most challenging health issues in urban areas worldwide. The aim of this study was to investigate the association between short-term exposure to ambient air pollution and respiratory disease over a long-term period in Shiraz, one of the largest cities in Iran. Methods: hospital admissions due to respiratory diseases (asthma, pneumonia, chronic obstructive pulmonary disease(COPD) and pleural effusion) in residents of Shiraz between March 21, 2009 and March 20, 2015 were included. Demographics for each patient and meta data to include principal meteorological variables (temperature and relative humidity) and five ambient pollutants (CO, O 3 , SO 2 , NO 2 , and PM 10 ) were also included. Statistical analysis was performed by Poisson regression in single-pollutant generalized linear model with principal component analysis (GLPCA) to analyze the relationship between pollutants and hospital admissions at the 0–9 cumulative lag day period. Pearson correlation test was used to determine the relationship between different pollutants, temperature and humidity. Results It was found that the highest increase in asthma admission was related to PM 10 (relative risk (RR) = 1.31, 95% CI = 1.17, 1.47). For COPD, the rate of hospital visits significantly increased with the increase in NO 2 concentration (RR = 1.17, 95% CI = 1.09.1.27). In the children's hospital, O 3 (RR = 1.25, 95% CI = 1.06, 1.47) and SO 2 (RR = 1.17, 95% CI = 1.07, 1.28) affected the asthma admissions and all contaminants (highest RR observed was for NO 2 (RR = 1.28 95% CI = 1.18, 1.40) affected pneumonia admissions on cumulative lag days of 0–9. Conclusions: These data confirm an association between ambient air pollutants and hospital admissions due to respiratory disease.

Shiraz↗

USGS2014

Concurrent photolytic degradation of aqueous methylmercury and dissolved organic matter

Monomethyl mercury (MeHg) is a potent neurotoxin that threatens ecosystem viability and human health. In aquatic systems, the photolytic degradation of MeHg (photodemethylation) is an important component of the MeHg cycle. Dissolved organic matter (DOM) is also affected by exposure to solar radiation (light exposure) leading to changes in DOM composition that can affect its role in overall mercury (Hg) cycling. This study investigated changes in MeHg concentration, DOM concentration, and the optical signature of DOM caused by light exposure in a controlled field-based experiment using water samples collected from wetlands and rice fields. Filtered water from all sites showed a marked loss in MeHg concentration after light exposure. The rate of photodemethylation was 7.5 × 10 -3 m 2 mol -1 (s.d. 3.5 × 10 -3 ) across all sites despite marked differences in DOM concentration and composition. Light exposure also caused changes in the optical signature of the DOM despite there being no change in DOM concentration, indicating specific structures within the DOM were affected by light exposure at different rates. MeHg concentrations were related to optical signatures of labile DOM whereas the percent loss of MeHg was related to optical signatures of less labile, humic DOM. Relationships between the loss of MeHg and specific areas of the DOM optical signature indicated that aromatic and quinoid structures within the DOM were the likely contributors to MeHg degradation, perhaps within the sphere of the Hg-DOM bond. Because MeHg photodegradation rates are relatively constant across freshwater habitats with natural Hg–DOM ratios, physical characteristics such as shading and hydrologic residence time largely determine the relative importance of photolytic processes on the MeHg budget in these mixed vegetated and open-water systems.

Science of the Total Environment↗

USGS2021

Machine learning predictions of nitrate in groundwater used for drinking supply in the conterminous United States

Groundwater is an important source of drinking water supplies in the conterminous United State (CONUS), and presence of high nitrate concentrations may limit usability of groundwater in some areas because of the potential negative health effects. Prediction of locations of high nitrate groundwater is needed to focus mitigation and relief efforts. A three-dimensional extreme gradient boosting (XGB) machine learning model was developed to predict the distribution of nitrate. Nitrate was predicted at a 1 km resolution for two drinking water zones, each of variable depth, one for domestic supply and one for public supply. The model used measured nitrate concentrations from 12,082 wells and included predictor variables representing well characteristics, hydrologic conditions, soil type, geology, land use, climate, and nitrogen inputs. Predictor variables derived from empirical or numerical process-based models were also included to integrate information on controlling processes and conditions. The model provided accurate estimates at national and regional scales: the training (R 2 of 0.83) and hold-out (R 2 of 0.49) data fits compared favorably to previous studies. Predicted nitrate concentrations were less than 1 mg/L across most of the CONUS. Nationally, well depth, soil and climate characteristics, and the absence of developed land use were among the most influential explanatory factors. Only 1% of the area in either water supply zone had predicted nitrate concentrations greater than 10 mg/L; however, about 1.4 M people depend on groundwater for their drinking supplies in those areas. Predicted high concentrations of nitrate were most prevalent in the central CONUS. In areas of predicted high nitrate concentration, applied manure, farm fertilizer , and agricultural land use were influential predictor variables. This work represents the first application of XGB to a three-dimensional national-scale groundwater quality model and provides a significant milestone in the efforts to document nitrate in groundwater across the CONUS.

Science of the Total Environment↗

USGS2020

Methylmercury exposure in wildlife: A review of the ecological and physiological processes affecting contaminant concentrations and their interpretation

Exposure to methylmercury (MeHg) can result in detrimental health effects in wildlife. With advances in ecological indicators and analytical techniques for measurement of MeHg in a variety of tissues, numerous processes have been identified that can influence MeHg concentrations in wildlife. This review presents a synthesis of theoretical principals and applied information for measuring MeHg exposure and interpreting MeHg concentrations in wildlife. Mercury concentrations in wildlife are the net result of ecological processes influencing dietary exposure combined with physiological processes that regulate assimilation, transformation, and elimination. Therefore, consideration of both physiological and ecological processes should be integrated when formulating biomonitoring strategies. Ecological indicators, particularly stable isotopes of carbon, nitrogen, and sulfur, compound-specific stable isotopes, and fatty acids, can be effective tools to evaluate dietary MeHg exposure. Animal species differ in their physiological capacity for MeHg elimination, and animal tissues can be inert or physiologically active, act as sites of storage, transformation, or excretion of MeHg, and vary in the timing of MeHg exposure they represent. Biological influences such as age, sex, maternal transfer, and growth or fasting are also relevant for interpretation of tissue MeHg concentrations. Wildlife tissues that represent current or near-term bioaccumulation and in which MeHg is the predominant mercury species (such as blood and eggs) are most effective for biomonitoring ecosystems and understanding landscape drivers of MeHg exposure. Further research is suggested to critically evaluate the use of keratinized external tissues to measure MeHg bioaccumulation, particularly for less-well studied wildlife such as reptiles and terrestrial mammals. Suggested methods are provided to effectively use wildlife for quantifying patterns and drivers of MeHg bioaccumulation over time and space, as well as for assessing the potential risk and toxicological effects of MeHg on wildlife.

Science of the Total Environment↗