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Peter C. Van Metre

Publications and source records attributed to Peter C. Van Metre.

At least 55 records · Page 3Linked to original sources
USGS2016

Metformin and other pharmaceuticals widespread in wadeable streams of the southeastern United States

Pharmaceutical contaminants are growing aquatic-health concerns and largely attributed to wastewater treatment facility (WWTF) discharges. Five biweekly water samples from 59 small Piedmont (United States) streams were analyzed for 108 pharmaceuticals and degradates using high-performance liquid chromatography and tandem mass spectrometry. The antidiabetic metformin was detected in 89% of samples and at 97% of sites. At least one pharmaceutical was detected at every site (median of 6, maximum of 45), and several were detected at ≥10% of sites at concentrations reported to affect multiple aquatic end points. Maximal cumulative (all detected compounds) concentrations per site ranged from 17 to 16000 ng L –1 . Watershed urbanization, water table depth, soil thickness, and WWTF metrics correlated significantly with in-stream pharmaceutical contamination. Comparable pharmaceutical concentrations and detections at sites with and without permitted wastewater discharges demonstrate the importance of non-WWTF sources and the need for broad-scale mitigation. The results highlight a fundamental biochemical link between global human-health crises like diabetes and aquatic ecosystem health.

Environmental Science & Technology Letters↗
USGS2016

The Northeast Stream Quality Assessment

In 2016, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) is assessing stream quality in the northeastern United States. The goal of the Northeast Stream Quality Assessment (NESQA) is to assess the quality of streams in the region by characterizing multiple water-quality factors that are stressors to aquatic life and evaluating the relation between these stressors and biological communities. The focus of NESQA in 2016 will be on the effects of urbanization and agriculture on stream quality in all or parts of eight states: Connecticut, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. Findings will provide the public and policymakers with information about the most critical factors affecting stream quality, thus providing insights about possible approaches to protect the health of streams in the region. The NESQA study will be the fourth regional study conducted as part of NAWQA and will be of similar design and scope to the first three, in the Midwest in 2013, the Southeast in 2014, and the Pacific Northwest in 2015 ( http://txpub.usgs.gov/RSQA/ ).

Connecticut, Massachusetts, New Hampshire, New Jer↗
USGS2016

Coal-tar-based pavement sealcoat—Potential concerns for human health and aquatic life

Introduction Sealcoat is the black, viscous liquid sprayed or painted on many asphalt parking lots, driveways, and playgrounds to protect and enhance the appearance of the underlying asphalt. Studies by the U.S. Geological Survey (USGS), academic institutions, and State and local agencies have identified coal-tar-based pavement sealcoat as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban and suburban areas and a potential concern for human health and aquatic life. Key Findings: Human Health Concerns —As coal-tar-based sealcoat ages, it wears into small particles with high levels of PAHs that can be tracked into homes and incorporated into house dust. For people who live adjacent to coal-tar-sealcoated pavement, ingestion of PAH-contaminated house dust and soil results in an elevated potential cancer risk, particularly for young children. Exposure to PAHs, especially early in childhood, has been linked by health professionals to an increased risk of lung, skin, bladder, and respiratory cancers. Aquatic Life Concerns —Runoff from coal-tar-sealcoated pavement, even runoff collected more than 3 months after sealcoat application, is acutely toxic to fathead minnows and water fleas, two species commonly used to assess toxicity to aquatic life. Exposure to even highly diluted runoff from coal-tar-sealcoated pavement can cause DNA damage and impair DNA repair. These findings demonstrate that coal-tar-sealcoat runoff can remain a risk to aquatic life for months after application.

Fact Sheet↗
USGS2016

Spatial and temporal variation in microcystins occurrence in wadeable streams in the southeastern USA

Despite historical observations of potential microcystin-producing cyanobacteria (including Leptolyngbya , Phormidium , Pseudoanabaena , and Anabaena species) in 74% of headwater streams in Alabama, Georgia, South Carolina, and North Carolina (USA) from 1993 to 2011, fluvial cyanotoxin occurrence has not been systematically assessed in the southeastern United States. To begin to address this data gap, a spatial reconnaissance of fluvial microcystin concentrations was conducted in 75 wadeable streams in the Piedmont region (southeastern USA) during June 2014. Microcystins were detected using enzyme-linked immunosorbent assay (limit = 0.10 µg/L) in 39% of the streams with mean, median, and maximum detected concentrations of 0.29 µg/L, 0.11 µg/L, and 3.2 µg/L, respectively. Significant (α = 0.05) correlations were observed between June 2014 microcystin concentrations and stream flow, total nitrogen to total phosphorus ratio, and water temperature; but each of these factors explained 38% or less of the variability in fluvial microcystins across the region. Temporal microcystin variability was assessed monthly through October 2014 in 5 of the streams where microcystins were observed in June and in 1 reference location; microcystins were repeatedly detected in all but the reference stream. Although microcystin concentrations in the present study did not exceed World Health Organization recreational guidance thresholds, their widespread occurrence demonstrates the need for further investigation of possible in-stream environmental health effects as well as potential impacts on downstream lakes and reservoirs. Environ Toxicol Chem 2016;9999:1–7. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.

Alabama, Georgia, Maryland, North Carolina, South ↗
USGS2016

Spatiotemporal patterns of mercury accumulation in lake sediments of western North America

For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.2 μg/m 2 per year. Lakes with the greatest increases were influenced by the Flin Flon smelter, followed by lakes directly affected by mining and wastewater discharges. Of lakes not directly affected by point sources, there is a clear separation in mercury accumulation rates between lakes with no/little watershed development and lakes with extensive watershed development for agricultural and/or residential purposes. Lakes in the latter group exhibited a sharp increase in mercury accumulation rates with human settlement, stabilizing after 1950 at five times (5×) 1850 rates. Mercury accumulation rates in lakes with no/little watershed development were controlled primarily by relative watershed size prior to 1850, and since have exhibited modest increases (in absolute terms and compared to that described above) associated with (regional and global) industrialization. A sub-regional analysis highlighted that in the ecoregion Northwestern Forest Mountains, <1% of mercury deposited to watersheds is delivered to lakes. Research is warranted to understand whether mountainous watersheds act as permanent sinks for mercury or if export of “legacy” mercury (deposited in years past) will delay recovery when/if emissions reductions are achieved.

Alaska, Alberta, Arizona, British Columbia, Califo↗
USGS2016

High nitrate concentrations in some Midwest United States streams in 2013 after the 2012 drought

Nitrogen sources in the Mississippi River basin have been linked to degradation of stream ecology and to Gulf of Mexico hypoxia. In 2013, the USGS and the USEPA characterized water quality stressors and ecological conditions in 100 wadeable streams across the midwestern United States. Wet conditions in 2013 followed a severe drought in 2012, a weather pattern associated with elevated nitrogen concentrations and loads in streams. Nitrate concentrations during the May to August 2013 sampling period ranged from <0.04 to 41.8 mg L −1 as N (mean, 5.31 mg L −1 ). Observed mean May to June nitrate concentrations at the 100 sites were compared with May to June concentrations predicted from a regression model developed using historical nitrate data. Observed concentrations for 17 sites, centered on Iowa and southern Minnesota, were outside the 95% confidence interval of the regression-predicted mean, indicating that they were anomalously high. The sites with a nitrate anomaly had significantly higher May to June nitrate concentrations than sites without an anomaly (means, 19.8 and 3.6 mg L −1 , respectively) and had higher antecedent precipitation indices, a measure of the departure from normal precipitation, in 2012 and 2013. Correlations between nitrate concentrations and watershed characteristics and nitrogen and oxygen isotopes of nitrate indicated that fertilizer and manure used in crop production, principally corn, were the dominant sources of nitrate. The anomalously high nitrate levels in parts of the Midwest in 2013 coincide with reported higher-than-normal nitrate loads in the Mississippi River.

Journal of Environmental Quality↗
USGS2015

Declining Dioxin concentrations in the Rhone River, France, attest to the effectiveness of emissions controls

Emission-control policies have been implemented in Europe and North America since the 1990s for polychlorodibenzodioxins (PCDDs) and furans (PCDFs). To assess the effect of these policies on temporal trends and spatial patterns for these compounds in a large European river system, sediment cores were collected in seven depositional areas along the Rhone River in France, dated, and analyzed for PCDDs and PCDFs. Results show concentrations increase in the downstream direction and have decreased temporally at all sites during the last two decades, with an average decrease of 83% from 1992 to 2010. The time for a 50% decrease in concentrations (t1/2) averaged 6.9 &plusmn; 2.6 and 9.1 &plusmn; 2.9 years for the sum of measured PCDDs and PCDFs, respectively. Congener patterns are similar among cores and indicate dominance of regional atmospheric deposition and possibly weathered local sources. Local sources are clearly indicated at the most downstream site, where concentrations of the most toxic dioxin, TCDD, are about 2 orders of magnitude higher than at the other six sites. The relatively steep downward trends attest to the effects of the dioxin emissions reduction policy in Europe and suggest that risks posed to aquatic life in the Rhone River basin from dioxins and furans have been greatly reduced.

Environmental Science & Technology↗
USGS2015

Paleoreconstruction of organic carbon inputs to an oxbow lake in the Mississippi River watershed: Effects of dam construction and land use change on regional inputs

We use a dated sediment core from Lake Whittington (USA) in the lower Mississippi River to reconstruct linkages in the carbon cycling and fluvial sediment dynamics over the past 80&thinsp;years. Organic carbon (OC) sources were characterized using bulk (&delta; 13 C, ramped pyrolysis-oxidation (PyrOx) 14 C, &delta; 15 N, and TN:OC ratios) and compound-specific (lignin phenols and fatty acids, including &delta; 13 C and 14 C of the fatty acids) analyses. Damming of the Missouri River in the 1950s, other hydrological modifications to the river, and soil conservation measures resulted in reduced net OC export, in spite of increasing OC concentrations. Decreasing &delta; 13 C values coincided with increases in &delta; 15 N, TN:OC ratios, long-chain fatty acids, and lignin-phenol concentrations, suggesting increased inputs of soil-derived OC dominated by C 3 vegetation, mainly resulting from changes in farming practices and crop distribution. However, ramped PyrOx 14 C showed no discernible differences downcore in thermochemical stability, indicating a limited impact on soil OC turnover.

Mississippi↗
USGS2015

Design and methods of the Southeast Stream Quality Assessment (SESQA), 2014

During 2014, the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) assessed stream quality across the Piedmont and southern Appalachian Mountain regions of the southeastern United States. This Southeast Stream Quality Assessment (SESQA) simultaneously characterized watershed and stream-reach water-quality stressors along with instream biological conditions, in order to better understand regional stressor-effects relations. The goal of SESQA is to provide communities and policymakers with information about those human and environmental factors that have the greatest impact on stream quality across the region. The SESQA design focused on hydrologic alteration and urbanization because of their importance as ecological stressors of particular concern to Southeast region resource managers. Streamflow and land-use data were used to identify and select sites representing gradients in urbanization and streamflow alteration across the region. One hundred fifteen sites were selected and sampled for as many as 10 weeks during April, May, and June 2014 for contaminants, nutrients, and sediment. This water-quality &ldquo;index&rdquo; period culminated with an ecological survey of habitat, periphyton, benthic macroinvertebrates, and fish at all sites. Sediment was collected during the ecological survey for analysis of sediment chemistry and toxicity testing. Of the 115 sites, 59 were on streams in watersheds with varying degrees of urban land use, 5 were on streams with multiple confined animal feeding operations, and 13 were reference sites with little or no development in their watersheds. The remaining 38 &ldquo;hydro&rdquo; sites were on streams in watersheds with relatively little agricultural or urban development but with hydrologic alteration, such as a dam or reservoir. This report provides a detailed description of the SESQA study components, including surveys of ecological conditions, routine water sampling, deployment of passive polar organic compound integrative samplers for pesticides and contaminants of emerging concern, and synoptic sediment sampling and toxicity testing at all urban, confined animal feeding operation, and reference sites. Continuous water-quality monitoring and daily pesticide sampling efforts conducted at a subset of urban sites are also described.

Alabama, Georgia, North Carolina, South Carolina, ↗
USGS2015

Acute toxicity of runoff from sealcoated pavement to Ceriodaphnia dubia and Pimephales promelas

Runoff from coal-tar-based (CT) sealcoated pavement is a source of polycyclic aromatic hydrocarbons (PAHs) and N -heterocycles to surface waters. We investigated acute toxicity of simulated runoff collected from 5 h to 111 days after application of CT sealcoat and from 4 h to 36 days after application of asphalt-based sealcoat containing about 7% CT sealcoat (AS/CT-blend). Ceriodaphnia dubia (cladocerans) and Pimephales promelas (fathead minnows) were exposed in the laboratory to undiluted and 1:10 diluted runoff for 48 h, then transferred to control water and exposed to 4 h of ultraviolet radiation (UVR). Mortality following exposure to undiluted runoff from unsealed asphalt pavement and UVR was &le;10% in all treatments. Test organisms exposed to undiluted CT runoff samples collected during the 3 days ( C. dubia ) or 36 days ( P. promelas ) following sealcoat application experienced 100% mortality prior to UVR exposure; with UVR exposure, mortality was 100% for runoff collected across the entire sampling period. Phototoxic-equivalent PAH concentrations and mortality demonstrated an exposure-response relation. The results indicate that runoff remains acutely toxic for weeks to months after CT sealcoat application.

Environmental Science & Technology↗
USGS2015

Tracing historical trends of Hg in the Mississippi River using Hg concentrations and Hg isotopic compositions in a lake sediment core, Lake Whittington, Mississippi, USA

Concentrations and isotopic compositions of mercury (Hg) in a sediment core collected from Lake Whittington, an oxbow lake on the Lower Mississippi River, were used to evaluate historical sources of Hg in the Mississippi River basin. Sediment Hg concentrations in the Lake Whittington core have a large 10-15 y peak centered on the 1960s, with a maximum enrichment factor relative to Hg in the core of 4.8 in 1966. The Hg concentration profile indicates a different Hg source history than seen in most historical reconstructions of Hg loading. The timing of the peak is consistent with large releases of Hg from Oak Ridge National Laboratory (ORNL), primarily in the late 1950s and 1960s. Mercury was used in a lithiumisotope separation process by ORNL and an estimated 128Mg (megagrams) of Hgwas discharged to a local stream that flows into the Tennessee River and, eventually, the Mississippi River. Mass balance analyses of Hg concentrations and isotopic compositions in the Lake Whittington core fit a binary mixing model with a Hg-rich upstream source contributing about 70% of the Hg to Lake Whittington at the height of the Hg peak in 1966. This upstream Hg source is isotopically similar to Hg isotope compositions of stream sediment collected downstream near ORNL. It is estimated that about one-half of the Hg released from the ORNL potentially reached the LowerMississippi River basin in the 1960s, suggesting considerable downstream transport of Hg. It is also possible that upstream urban and industrial sources contributed some proportion of Hg to Lake Whittington in the 1960s and 1970s.

Chemical Geology↗
USGS2015

Exposure to runoff from coal-tar-sealed pavement induces genotoxicity and impairment of DNA repair capacity in the RTL-W1 fish liver cell line

Coal-tar-based (CTB) sealcoat, frequently applied to parking lots and driveways in North America, contains elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and related compounds. The RTL-W1 fish liver cell line was used to investigate two endpoints (genotoxicity and DNA-repair-capacity impairment) associated with exposure to runoff from asphalt pavement with CTB sealcoat or with an asphalt-based sealcoat hypothesized to contain about 7% CTB sealcoat (AS-blend). Genotoxic potential was assessed by the Formamido pyrimidine glycosylase (Fpg)-modified comet assay for 1:10 and 1:100 dilutions of runoff samples collected from 5 h to 36 d following sealcoat application. DNA-repair capacity was assessed by the base excision repair comet assay for 1:10 dilution of samples collected 26 h and 36 d following application. Both assays were run with and without co-exposure to ultraviolet-A radiation (UVA). With co-exposure to UVA, genotoxic effects were significant for both dilutions of CTB runoff for three of four sample times, and for some samples of AS-blend runoff. Base excision repair was significantly impaired for CTB runoff both with and without UVA exposure, and for AS-blend runoff only in the absence of UVA. This study is the first to investigate the effects of exposure to the complex mixture of chemicals in coal tar on DNA repair capacity. The results indicate that co-exposure to runoff from CT-sealcoated pavement and UVA as much as a month after sealcoat application has the potential to cause genotoxicity and impair DNA repair capacity.

Science of the Total Environment↗
USGS2015

The Pacific northwest stream quality assessment

In 2015, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program is assessing stream quality in the Pacific Northwest. The goals of the Pacific Northwest Stream Quality Assessment (Pacific Northwest study) are to assess the quality of streams in the region by characterizing multiple water-quality factors that are stressors to aquatic life and to evaluate the relation between these stressors and biological communities. The effects of urbanization and agriculture on stream quality for the Puget Lowlands and Willamette Valley are the focus of this regional study. Findings will provide the public and policymakers with information regarding which human and environmental factors are the most critical in affecting stream quality and, thus, provide insights about possible approaches to protect or improve the health of streams in the region. The Pacific Northwest study will be the third regional study by the NAWQA program, and it will be of similar design and scope as the first two&mdash;the Midwest in 2013 and the Southeast in 2014 (Van Metre and others, 2012, 2014).

Oregon, Washington↗
USGS2014

Zinc isotopic signatures in eight lake sediment cores from across the United States

Zinc is an important trace element pollutant in urban environments; however, the extent of Zn contamination and the sources of urban Zn pollution are often unclear. We measured Zn concentrations and isotopes in sediment cores collected from eight lakes or reservoirs across the United States. We paired these data with historical records of land use within each watershed to calculate a mean Zn concentration and δ 66 Zn for natural (less than 5% urban land use; 123 ± 21.7 mg/kg; +0.33 ± 0.08‰, n = 6 lakes) and urban (greater than 70% urban land use; 389 ± 200 mg/kg; +0.14 ± 0.07‰, n = 3 lakes) lake sediments. The relation between Zn concentration data and Zn isotope data allows us to create a mixing model between two end members: natural and urban. The δ 66 Zn of the urban end-member is consistent with Zn pollution from vehicle-related sources (tire wear and emissions). Application of this model to samples collected from lakes recording periods ranging from 5 to 70% urban land use in their surrounding watersheds indicates that the lakes and reservoirs were affected by large amounts of Zn from urban sources.

conterminous United States↗
USGS2014

PAH concentrations in lake sediment decline following ban on coal-tar-based pavement sealants in Austin, Texas

Recent studies have concluded that coal-tar-based pavement sealants are a major source of polycyclic aromatic hydrocarbons (PAHs) in urban settings in large parts of the United States. In 2006, Austin, TX, became the first jurisdiction in the U.S. to ban the use of coal-tar sealants. We evaluated the effect of Austin’s ban by analyzing PAHs in sediment cores and bottom-sediment samples collected in 1998, 2000, 2001, 2012, and 2014 from Lady Bird Lake, the principal receiving water body for Austin urban runoff. The sum concentration of the 16 EPA Priority Pollutant PAHs (∑PAH 16 ) in dated core intervals and surficial bottom-sediment samples collected from sites in the lower lake declined about 44% from 1998–2005 to 2006–2014 (means of 7980 and 4500 μg kg –1 , respectively), and by 2012–2014, the decline was about 58% (mean of 3320 μg kg –1 ). Concentrations of ∑PAH 16 in bottom sediment from two of three mid-lake sites decreased by about 71 and 35% from 2001 to 2014. Concentrations at a third site increased by about 14% from 2001 to 2014. The decreases since 2006 reverse a 40-year (1959–1998) upward trend. Despite declines in PAH concentrations, PAH profiles and source-receptor modeling results indicate that coal-tar sealants remain the largest PAH source to the lake, implying that PAH concentrations likely will continue to decline as stocks of previously applied sealant gradually become depleted.

Texas↗
USGS2014

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement.

Environmental Pollution↗
USGS2014

Effects of urbanization on mercury deposition and accumulation in New England

We compare total mercury (HgT) loading and methylmercury (MeHg) accumulation in streams and lakes from an urbanized area (Boston, Massachusetts) to rural regions of southern New Hampshire and Maine. The maximum HgT loading, as indicated by HgT atmospheric deposition, HgT emissions, and sediment HgT concentrations, did not coincide with maximum MeHg concentrations in fish. Urbanized ecosystems were areas of high HgT loading but had low MeHg concentrations in fish. Controls on MeHg production and accumulation appeared to be related primarily to HgT loading in undeveloped areas, while ecosystem sensitivity to MeHg formation appeared to be more important in regulating accumulation of MeHg in the urban area.

Connecticut, Maine, Massachusetts, New Hampshire, ↗