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At least 145 records · Page 8Linked to original sources
USGS1998

Occurrence and distribution of semivolatile organic compounds in stream bed sediments, United States, 1992-95

Bed-sediment samples from streams were collected from 443 sites in 19 major river basins during 1992-95 and analyzed for semivolatile organic compounds (SVOCs) to assess the occurrence and distribution of selected Hydrophobic contaminants. Forty SVOCs were detected in more than 5 percent of samples. Of these 40 SVOCs, 27 were polycyclic aromatic hydrocarbons (PAHs), 5 were azaarenes, 5 were phthalates, 2 were phenols, and 1 was a quinone. Statistically higher concentrations of the sum of PAHs, azaarenes, and phthalates were measured in samples from urban drainage basins in comparison to other land uses. The frequency of detection and concentrations of PAHs, azaarenes, and phthalates were highest in the northeastern part and lowest in the western part of the United States. Concentrations of the sum of PAHs and sum of phthalates had statistically significant, but weak, correlations with toxic releases to air, population density, and urban land use. Urban activities could be significant sources and the atmosphere could be a significant transport mechanism affecting the distribution of certain SVOCs.

Book chapter↗
USGS2000

Effects of a Cattail Wetland on Water Quality of Irondequoit Creek near Rochester, New York

A 6-year (1990-96) study of the Ellison Park wetland, a 423-acre, predominantly cattail ( Typha glauca ) marsh in Monroe County, N.Y., was conducted to document the effect that this wetland has on the water quality of Irondequoit Creek, which flows through it. Irondequoit Creek drains 151 square miles of mostly urban and suburban land and is the main tributary to Irondequoit Bay on Lake Ontario. The wetland was a sink for total phosphorus and total suspended solids (28 and 47 percent removal efficiencies, respectively, over the 6-year study period). Sedimentation and vegetative filtration appear to be the primary mechanisms for the decrease in loads of these constituents. Total nitrogen loads were decreased slightly by the wetland; removal efficiencies for ammonia-plus-organic nitrogen and nitrate-plus-nitrite were 6 and 3 percent, respectively. The proportions of total phosphorus and total nitrogen constituents were altered by the wetland. Orthophosphate and ammonia nitrogen were generated within the wetland and represented 12 percent of the total phosphorus output load and 1.8 percent of total nitrogen output load, respectively. Conservative chemicals, such as chloride and sulfate, were littleaffected by the wetland. Concentrations of zinc, lead, and cadmium showed statistically significant decreases, which are attributed to sedimentation and filtration of sediment and organic matter to which these elements adsorb. Sediment samples from open-water depositional areas in the wetland contained high concentrations of (1) trace metals, including barium, manganese, strontium, zinc (each of which exceeded 200 parts per million), as well as chromium, copper, lead, and vanadium, and (2) some polycyclic aromatic hydrocarbons. Persistent organochlorine pesticides, such as chlordane, dieldrin, DDT and its degradation products (DDD and DDE), and polychlorinated biphenyls (PCB's), also were detected, but concentrations of these compounds were within the ranges often found in depositional environments in highly urbanized areas. Cattail shoots attained a maximum height of 350 centimeters, a density of more than 30 shoots per square meter, and total biomass of more than 5,600 grams per square meter (46 percent of which was in above-ground tissues during the growing season). Nitrogen and potassium were three times more abundant in above-ground tissues (2.4 and 1.5 percent by dry weight, respectively) than in below-ground tissues (0.8 and 0.5 percent, respectively). Concentrations of phosphorus, molybdenum, and manganese in above-ground tissues were similar to those in below-ground tissues, but the concentrations of all other constituents were considerably higher in below-ground tissues. Concentrations of several elements exceeded those typically found in natural wetlands; these included manganese (417 ppm, parts per million) and sodium (3,600 ppm) in above-ground tissues, and aluminum (1,540 ppm), iron (15,400 ppm), manganese (433 ppm), and sodium (10,000 ppm) in below-ground tissues. Large quantities of nutrients are assimilated by wetland vegetation during the growing season, but neither tissue production nor microbial metabolic processes appeared to play a significant role in the observed patterns of surface-water chemical input-to-output relations on a seasonal basis. Presumably, internal cycling of nutrients sequestered in the sediments and detritus, combined with a summer increase in microbially mediated chemical transformations, obscured the effects of vegetative assimilation during the summer on surface-water chemical loads. Additionally, the natural confinement of most flows within the banks of Irondequoit Creek, which resulted in passage of stormwater through the wetland with little dispersion or detention in the cattail and backwater areas, diminished the capability of the wetland to improve water quality. Additional factors that probably affected the chemical-removal efficiency of the wetland included chemical inflow loading rates, storage and release mechanisms of the sediments (sedimentation, adsorption, filtration, precipitaton, dissolution, and resuspension), and accretion and burial of organic matter. Measurements of chlorophyll_ a concentrations, and calculations of potential phosphorus concentrations, since the 1970’s indicate an improvement in the trophic state of Irondequoit Bay. Estimated average annual loads (1990-96) of selected constituents entering Irondequoit Bay indicate that, since 1980, the loads of all major forms of nitrogen have decreased, chloride loads have increased, and sulfate loads have changed little. Inputs of total phosphorus and suspended solids to the wetland have increased since 1980, possibly as a result of increased erosion by stormflows from an increasingly developed watershed. The wetland decreases the loads of these constituents, but the trends of these loads entering Irondequoit Bay cannot be reliably defined because the removal efficiencies during the two earlier study periods (1980–81 and 1984–88) are known.

Water-Resources Investigations Report↗
USGS2004

Organic contaminants associated with suspended sediment collected during five cruises of the Mississippi River and its principal tributaries, May 1988 to June 1990

Suspended-sediment samples were obtained from sites along the Mississippi River and its principal tributaries to determine the presence of halogenated hydrophobic organic compounds on the suspended sediment smaller than 63 micrometers. Sample collection involved pumping discharge-weighted volumes of river water along a cross section of the river into a continuous-flow centrifuge to isolate the suspended sediment. The suspended sediment was analyzed by gas chromatography/mass spectrometry for pentachlorobenzene, hexachlorobenzene, pentachloroanisole, chlorothalonil, pentachlorophenol, dachthal, chlordane, nonachlor, and penta-, hexa-, hepta-, and octachlorobiphenyls. Samples collected during June 1989 and February-March 1990 also were analyzed for U.S. Environmental Protection Agency priority pollutants, including polycyclic aromatic hydrocarbons, phthalate esters, and triazines. Samples were collected at sites on the Mississippi River from above St. Louis, Missouri to below New Orleans, Louisiana, and on the Illinois, Missouri, Ohio, Wabash, Cumberland, Tennessee, White, Arkansas, and Yazoo Rivers. Masses of selected halogenated hydrophobic organic compounds associated with the suspended sediment at each site are presented in this report in tabular format, along with suspended-sediment concentration, water discharge, and organic-carbon content.

Mississippi River↗
USGS2008

Collection and analysis of samples for polycyclic aromatic hydrocarbons in dust and other solids related to sealed and unsealed pavement from 10 cities across the United States, 2005-07

Parking lots and driveways are dominant features of the modern urban landscape, and in the United States, sealcoat is widely used on these surfaces. One of the most widely used types of sealcoat contains refined coal tar; coal-tar-based sealcoat products have a mean polycyclic aromatic hydrocarbon (PAH) concentration of about 5 percent. A previous study reported that parking lots in Austin, Texas, treated with coal-tar sealcoat were a major source of PAH compounds in streams. This report presents methods for and data from the analysis of concentrations of PAH compounds in dust from sealed and unsealed pavement from nine U.S. cities, and concentrations of PAH compounds in other related solid materials (sealcoat surface scrapings, nearby street dust, and nearby soil) from three of those same cities and a 10th city. Dust samples were collected by sweeping dust from areas of several square meters with a soft nylon brush into a dustpan. Some samples were from individual lots or driveways, and some samples consisted of approximately equal amounts of material from three lots. Samples were sieved to remove coarse sand and gravel and analyzed by gas chromatography/mass spectrometry. Concentrations of PAHs vary greatly among samples with total PAH (sigmaPAH), the sum of 12 unsubstituted parent PAHs, ranging from nondetection for all 12 PAHs (several samples from Portland, Oregon, and Seattle, Washington; sigmaPAH of less than 36,000 micrograms per kilogram) to 19,000,000 micrograms per kilogram for a sealcoat scraping sample (Milwaukee, Wisconsin). The largest PAH concentrations in dust are from a driveway sample from suburban Chicago, Illinois (sigmaPAH of 9,600,000 micrograms per kilogram).

Data Series↗
USGS2008

Oceanic loading of wildfire-derived organic compounds from a small mountainous river

Small mountainous rivers (SMRs) export substantial amounts of sediment into the world's oceans. The concomitant yield of organic carbon (OC) associated with this class of rivers has also been shown to be significant and compositionally unique. We report here excessively high loadings of polycyclic aromatic hydrocarbons (PAHs), lignin, and levoglucosan, discharged from the Santa Clara River into the Santa Barbara Channel. The abundance of PAHs, levoglucosan, and lignin in Santa Barbara Channel sediments ranged from 201.7 to 1232.3 ng gdw-1, 1.3 to 6.9 ??g gdw-1, and 0.3 to 2.2 mg per 100 mg of the sedimentary OC, respectively. Assuming a constant rate of sediment accumulation, the annual fluxes of PAHs, levoglucosan, and lignin, to the Santa Barbara Channel were respectively, 885.5 ?? 170.2 ng cm-2 a-1, 3.5 ?? 1.9 ??g cm-2 a-1 and 1.4 ?? 0.3 mg per 100 mg OC cm-2 a-1, over ???30 years. The close agreement between PAHs, levoglucosan, and lignin abundance suggests that the depositional flux of these compounds is largely biomass combustion-derived. To that end, use of the Santa Clara River as a model for SMRs suggests this class of rivers may be one of the largest contributors of pyrolyzed carbon to coastal systems and the open ocean. Wildfire associated carbon discharged from other high yield fluvial systems, when considered collectively, may be a significant source of lignin, pyrolytic PAHs, and other pyrogenic compounds to the ocean. Extrapolating these methods over geologic time may offer useful historical information about carbon sequestration and burial in coastal sediments and affect coastal carbon budgets. Copyright 2008 by the American Geophysical Union.

Journal of Geophysical Research G: Biogeosciences↗
USGS2002

Selected elements and organic chemicals in streambed sediment in the Salem area, Oregon, 1999

Analysis of streambed sediments in the Salem, Oregon, area showed anomalously large concentrations of some elements and organic chemicals, indicating contamination from anthropogenic and/or geologic sources. The streambed sediment sample from Clark Creek, an urban basin, had large concentrations of polycyclic aromatic hyrdocarbons (PAHs), organochlorines, cadmium, lead, and zinc. The sample from the East Fork of Pringle Creek, which is a mostly urban basin, had the highest concentrations of DDD, DDE, and DDT compounds. Aldrin was detected in streambed sediment at only one site, the East Fork of Pringle Creek. Ten of the 14 sites sampled had exceedances of the sediment quality guidelines of the Canadian Council of Ministers of the Environment (CCME), and 8 sites had exceedances of guidelines from the Puget Sound Dredged Disposal Analysis (PSDDA) Program. Trace element concentrations in the Salem area generally were similar to those found previously in the Willamette Basin and nationally. However, cadmium, lead, and zinc concentrations were larger in the sample from Clark Creek than for largest value for Willamette Basin data from earlier studies. Zinc concentrations in the sample from Clark Creek exceeded sediment quality guidelines from the CCME and PSDDA. p,p'-DDE, which is a persistent breakdown product of the banned organochlorine-insecticide, DDT, was detected at all sites. Total DDT (the sum of p,p'-DDD, p,p'-DDE, and p,p'-DDT) concentrations exceeded the PSDDA screening level at eight sites and exceeded twice the PSDDA maximum level at the East Fork of Pringle Creek. Cis- and trans- chlordanes were detected at about 80% of the sites. The concentration of total chlordane for the sample at Clark Creek was larger than for any sample from previous Willamette Basin studies. The largest concentration of dieldrin also was from the sample at Clark Creek, which was the only site that exceeded the CCME guideline for dieldrin. The high levels of contaminants in some Salem area streams indicates the need for further study to assess the biological effects of these contaminants. Future monitoring in the Salem area could include bioassays using benthic invertebrates and the measurement of organochlorine compounds, including DDT, DDE, DDD, and dieldrin in fish tissue. Because resident fish may be consumed by humans and wildlife, fish tissue analyses would be helpful to determine the health risk associated with fish consumption.

Water-Resources Investigations Report↗
USGS2022

Characterization of water quality, biology, and habitat of the Pearl River and selected tributaries contiguous to and within Tribal lands of the Pearl River Community of the Mississippi Band of Choctaw Indians, 2017–18

The U.S. Geological Survey, in cooperation with the Mississippi Band of Choctaw Indians (MBCI), conducted a baseline assessment of the physical, chemical, and biological quality of selected streams and rivers within and contiguous to the Pearl River Community (PRC) in 2017 and 2018. The MBCI is a federally recognized tribe with territories in Mississippi and Tennessee. MBCI Tribal government and communities have sovereign authority over their natural resources and are responsible for protecting the quality of waters within the Tribal lands from sources of pollution and restoring impaired waters. The quality of these surface waters has a profound effect upon the health and welfare of MBCI Tribal members. Data generated from this study may be used with other relevant water-quality data for comparison and development of Tribal water-quality standards. The PRC territory is drained by the Pearl River and associated tributaries. Water-quality and biological samples were collected and habitat surveys were conducted at sites on the mainstem of the Pearl River and major tributaries of the Pearl River—Wolf Creek, Beasha Creek, Jones Creek, and Kentawka Creek. The selected stream sites represent a range of land use/land cover and potential sources of alteration and contamination from within their respective drainage areas. In particular, Wolf Creek watershed has the highest relative percentage of developed land. Ambient physicochemical properties, major ions, nutrients, and organic wastewater compounds (OWCs) were analyzed quarterly from surface-water samples from October 2017 through August 2018. Physicochemical properties were also measured in June 2018 over a continuous 48-hour period. Trace elements and polycyclic aromatic hydrocarbons were analyzed from streambed sediments in August 2018. Biological samples included the collection of periphyton algae (August 2018), benthic macroinvertebrate (March 2017 and March 2018), and fish communities (April 2018). Physical stream habitat characteristics were assessed using qualitative (March 2017 and March 2018) and quantitative surveys (August 2018). While not directly applicable, the State of Mississippi Water Quality Standards were used as reference to evaluate Tribal water quality. Physicochemical water-quality constituents—water temperature, specific conductance (SC), pH, and dissolved oxygen (DO)—were generally within natural ranges among sites and samples, with a few exceptions that exceeded existing Mississippi water-quality standards. pH and DO periodically were below the minimum State standards at some sampled sites. Specific conductance was also relatively high at both Wolf Creek sites but did not exceed the existing maximum standard for recreational waters. The surface water among stream sites was predominantly calcium bicarbonate type, with a shift toward sodium-bicarbonate water type at the downstream Wolf Creek (Wolf DS) site. Major ion concentrations were generally highest at the Wolf Creek sites. Nutrient concentrations were also often highest at Wolf DS, but total nitrogen and total phosphorus periodically exceeded recommended State and Federal nutrient criteria thresholds among most sampled sites. Twenty-nine OWCs, including 10 known or suspected endocrine disruptors, were detected among sites. Concentrations of OWCs were relatively low, and only 19 percent of all detections were above the reporting level. Concentrations of copper and nickel in streambed sediments were detected above consensus-based threshold-effect concentrations (TECs) at one site each, and arsenic and chromium exceeded TECs at most sites. Concentrations of all polycyclic aromatic hydrocarbons in streambed sediments were low and well below TECs at all sites. The periphyton, macroinvertebrate, and fish communities at most sampled sites appear typical of central Mississippi streams; however, the diversity, composition, and abundance of taxa sampled from Wolf DS were particularly distinctive compared to other sampled stream sites. Periphyton taxa richness was low at both Wolf Creek sites, and both sites had greater abundances of diatom taxa, which are indicative of high nutrient concentrations, than of soft-algae taxa. Similarly, Wolf DS had relatively low macroinvertebrate diversity, the fewest Ephemeroptera, Plecoptera, and Trichoptera taxa, a high abundance of Tubificid taxa, and the lowest overall Mississippi-Benthic Index of Stream Quality score. Fish species richness was also relatively low at Wolf DS compared to some other sampled sites. Habitat characteristics also appeared to be generally typical of most central Mississippi streams. Qualitative habitat assessment scores were at or above the regional least disturbed streams for Wolf DS, the upstream Wolf Creek (Wolf US) site, and Jones Creek. Habitat scores among the remaining sites indicate fair conditions. Quantitative and qualitative habitat characteristics indicate relatively lower habitat quality at the two Beasha Creek sites.

Mississippi↗
USGS2005

Kovats and lee retention indices determined by gas chromatography/mass spectrometry for organic compounds of environmental interest

Retention indices of standard organic compounds of environmental interest were determined by gas chromatography/mass spectrometry, using a DB‐5 fused‐silica capillary column. Retention indices are useful references for tentative compound identification by gas chromatography, or confirmation by gas chromatography/mass spectrometry. They provide elution order for isomers that might be indistinguishable based on mass spectra. Modified Kovats and Lee retention indices are given for polycyclic aromatic hydrocarbons; sulfur heterocycles; nitrogen heterocycles; aromatic amines; oxygen heterocycles; phenols; alcohols; ketones; alkanes; nitriles; and methylesters of fatty, dicarboxylic, and aromatic acids for comparison and reference. Retention index values for heterocycles by gas chromatography/mass spectrometry are comparable with gas chromatography values previously reported.

Journal of Separation Science↗
USGS1998

Rapid toxicity assessment of sediments from estuarine ecosystems: A new tandem in vitro testing approach

Microtox® and Mutatox® were used to evaluate the acute toxicity and genotoxicity, respectively, of organic sediment extracts from Pensacola Bay and St. Andrew Bay, two estuaries that cover about 273 and 127 km 2 , respectively, along the Gulf coast of Florida, USA. The sensitivity and selectivity of these two bioluminescent toxicity assays were demonstrated in validation studies with over 50 pesticides, genotoxins, and industrial pollutants, both as single compounds and in complex mixtures. The 50% effective concentration (EC50) values of insecticides, petroleum products, and polychlorinated biphenyls determined by Microtox all tended to group around the mean EC50 value of 1.2 (0.8) mg/L. The polycyclic aromatic hydrocarbon sensitivity of Mutatox was in general similar to that reported in the Ames test. Surficial sediment samples were collected, extracted with dichloromethane, evaporated and concentrated under nitrogen, dissolved in dimethyl sulfoxide, assayed for acute toxicity and genotoxicity, and compared with reference sediments. Samples with low EC50 values, and determined to be genotoxic, were detected in Massalina Bayou, Watson Bayou, East Bay, and St. Andrew Bay–East in St. Andrew Bay as well as Bayou Grande, Bayou Chico, and Bayou Texar in Pensacola Bay. An overview of these data sets analyzed by Spearman rank correlation showed a significant correlation between acute toxicity and genotoxicity ( p < 0.05). Microtox and Mutatox in tandem was a sensitive, cost‐effective, and rapid (<24 h) screening tool that identified troublesome areas of pollution and assessed the potential sediment toxicity of lipophilic contaminants in aquatic ecosystems.

Environmental Toxicology and Chemistry↗
USGS1993

Environmental contaminants in canvasbacks wintering on San Francisco Bay, California

The concentrations of 11 trace elements, 21 organochlorines, 13 polycyclic aromatic hydrocarbons, and 13 aliphatic hydrocarbons were determined in canvasbacks (Aythya valisineria) wintering on San Francisco Bay, California during 1988. With the exception of Se, concentrations of potentially toxic elements were low. Similarly, concentrations of most organic compounds were near or below detection limits. Aliphatic hydrocarbons, PCBs, and DDE were common, but at levels lower than those known to be harmful to waterfowl. Innocuous trace elements (Cu, Fe, and Zn), which are often associated with anthropogenic contamination, occurred at high levels. Concentrations of toxic elements were several times lower and those of benign elements were similar or greater than concentrations reported for surf scoters (Melanitta perspicillata) or greater scaup (Aythya marila) from San Francisco Bay.

California Fish and Game↗
USGS1988

Accumulation and bioconcentration of polycyclic aromatic hydrocarbons in a nearshore estuarine environment near a Pensacola (Florida) creosote contamination site

Long-term accumulation of creosote wastes at a wood-preserving facility near Pensacola, Florida, has produced high levels of organic contamination of groundwaters near Pensacola Bay. Impacts of this contamination on the nearshore environment of the bay were examined by analysis of water, sediment and tissues of two mollusc species. One of the species (Thais haemastoma) was native to the study area. Individuals of the other test species (Crassostrea virginica) were placed in cages at the test sites for a 6-week period. Contamination at the nearshore estuarine sites was assessed by comparison to a control site in an uncontaminated area of the bay, as well as a small stream which forms a direct surface-water link between the creosote storage ponds and the bay. The study focused on polycyclic aromatic hydrocarbons (PAH), the primary components of creosote. Very little PAH in water or in the surface layer of estuarine sediments was detected, despite heavy pollution of the stream sediments. This is attributed to various degradation processes which attack the PAH compounds once they discharge into the estuary, and to the likelihood of intermittent and localised release of contaminants to the estuary. Examination of sediment cores and mollusc tissues, which provide a record integrated over time and space, revealed some accumulation of a few PAH, notably fluoranthene, pyrene, benzo(a)anthracene, chrysene and phenanthrene. In the sediments, the highest concentrations of these compounds appeared below the surface, within a depth range of 8-13 cm. Bioaccumulation of fluoranthene, pyrene and phenanthrene in both mollusc species was up to ten times greater at test sites than at the control site. This contrasts with naphthalene, the bioaccumulation of which was no greater at test sites than at the control site. These differences in bioaccumulation factors relate to structural chemistry of the compounds which control their solubility, bioavailability, susceptibility to degradation and capacity for depuration by the organism.Long-term accumulation of creosote wastes at a wood-preserving facility near Pensacola, Florida, has produced high levels of organic contamination of groundwaters near Pensacola Bay. Impacts of this contamination on the nearshore environment of the bay were examined by analysis of water, sediment and tissues of two mollusc species. Very little PAH in water or in the surface layer of estuarine sediments was detected, despite heavy pollution of the stream sediments. This is attributed to various degradation processes which attack the PAH compounds once they discharge into the estuary, and to the likelihood of intermittent and localized release of contaminants to the estuary. There was some accumulation of a few PAH, notably fluoranthene, pyrene, benzo(a)anthracene, chrysene and phenanthrene. In the sediments, the highest concentrations of these compounds appeared below the surface, within a depth range of 8-13 cm. Bioaccumulation of fluoranthene, pyrene and phenanthrene in both mollusc species was up to ten times greater at test sites than at the control site. Differences in bioaccumulation factors relate to structural chemistry of the compounds which control their solubility, bioavailability, susceptibility to degradation and capacity for depuration by the organism.

Florida↗
USGS2014

Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean

Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9–126 ng/m 3 (mean = 25 ± 34) at source and 0.05–0.71 ng/m 3 (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1–3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.

Caribbean;Sahara↗
USGS2003

Sediment quantity and quality in three impoundments in Massachusetts

As part of a study with an overriding goal of providing information that would assist State and Federal agencies in developing screening protocols for managing sediments impounded behind dams that are potential candidates for removal, the U.S Geological Survey determined sediment quantity and quality at three locations: one on the French River and two on Yokum Brook, a tributary to the west branch of the Westfield River. Data collected with a global positioning system, a geographic information system, and sediment-thickness data aided in the creation of sediment maps and the calculation of sediment volumes at Perryville Pond on the French River in Webster, Massachusetts, and at the Silk Mill and Ballou Dams on Yokum Brook in Becket, Massachusetts. From these data the following sediment volumes were determined: Perryville Pond, 71,000 cubic yards, Silk Mill, 1,600 cubic yards, and Ballou, 800 cubic yards. Sediment characteristics were assessed in terms of grain size and concentrations of potentially hazardous organic compounds and metals. Assessment of the approaches and methods used at study sites indicated that ground-penetrating radar produced data that were extremely difficult and time-consuming to interpret for the three study sites. Because of these difficulties, a steel probe was ultimately used to determine sediment depth and extent for inclusion in the sediment maps. Use of these methods showed that, where sampling sites were accessible, a machine-driven coring device would be preferable to the physically exhausting, manual sediment-coring methods used in this investigation. Enzyme-linked immunosorbent assays were an effective tool for screening large numbers of samples for a range of organic contaminant compounds. An example calculation of the number of samples needed to characterize mean concentrations of contaminants indicated that the number of samples collected for most analytes was adequate; however, additional analyses for lead, copper, silver, arsenic, total petroleum hydrocarbons, and chlordane are needed to meet the criteria determined from the calculations. Particle-size analysis did not reveal a clear spatial distribution pattern at Perryville Pond. On average, less than 65 percent of each sample was greater in size than very fine sand. The sample with the highest percentage of clay-sized particles (24.3 percent) was collected just upstream from the dam and generally had the highest concentrations of contaminants determined here. In contrast, more than 90 percent of the sediment samples in the Becket impoundments had grain sizes larger than very fine sand; as determined by direct observation, rocks, cobbles, and boulders constituted a substantial amount of the material impounded at Becket. In general, the highest percentages of the finest particles, clays, occurred in association with the highest concentrations of contaminants. Enzyme-linked immunosorbent assays of the Perryville samples showed the widespread presence of petroleum hydrocarbons (16 out of 26 samples), polycyclic aromatic hydrocarbons (23 out of 26 samples), and chlordane (18 out of 26 samples); polychlorinated biphenyls were detected in five samples from four locations. Neither petroleum hydrocarbons nor polychlorinated biphenyls were detected at Becket, and chlordane was detected in only one sample. All 14 Becket samples contained polycyclic aromatic hydrocarbons. Replicate quality-control analyses revealed consistent results between paired samples. Samples from throughout Perryville Pond contained a number of metals at potentially toxic concentrations. These metals included arsenic, cadmium, copper, lead, nickel, and zinc. At Becket, no metals were found in elevated concentrations. In general, most of the concentrations of organic compounds and metals detected in Perryville Pond exceeded standards for benthic organisms, but only rarely exceeded standards for human contact. The most highly contaminated samples were

Water-Resources Investigations Report↗
USGS2005

Environmental stresses and skeletal deformities in fish from the Willamette River, Oregon

The Willamette River, one of 14 American Heritage Rivers, flows through the most densely populated and agriculturally productive region of Oregon. Previous biological monitoring of the Willamette River detected elevated frequencies of skeletal deformities in fish from certain areas of the lower (Newberg pool [NP], rivermile [RM] 26−55) and middle (Wheatland Ferry [WF], RM 72−74) river, relative to those in the upper river (Corvallis [CV], RM 125−138). The objective of this study was to determine the likely cause of these skeletal deformities. In 2002 and 2003, deformity loads in Willamette River fishes were 2−3 times greater at the NP and WF locations than at the CV location. There were some differences in water quality parameters between the NP and CV sites, but they did not readily explain the difference in deformity loads. Concentrations of bioavailable metals were below detection limits (0.6−1 μg/L). Concentrations of bioavailable polychlorinated biphenyls (PCBs) and chlorinated pesticides were generally below 0.25 ng/L. Concentrations of bioavailable polycyclic aromatic hydrocarbons were generally less than 5 ng/L. Concentrations of most persistent organic pollutants were below detection limits in ovary/oocyte tissue samples and sediments, and those that were detected were not significantly different among sites. Bioassay of Willamette River water extracts provided no evidence that unidentified compounds or the complex mixture of compounds present in the extracts could induce skeletal deformities in cyprinid fish. However, metacercariae of a digenean trematode were directly associated with a large percentage of deformities detected in two Willamette River fishes, and similar deformities were reproduced in laboratory fathead minnows exposed to cercariae extracted from Willamette River snails. Thus, the weight of evidence suggests that parasitic infection, not chemical contaminants, was the primary cause of skeletal deformities observed in Willamette River fish.

Oregon↗
USGS2006

Investigations of the Effects of Synthetic Chemicals on the Endocrine System of Common Carp in Lake Mead, Nevada and Arizona

Introduction: Lake Mead is the largest reservoir by volume in the United States and was created by the construction of the 221-meter high Hoover Dam in 1935 at Black Canyon on the lower Colorado River between Nevada and Arizona (fig. 1). Inflows of water into the lake include three rivers, Colorado, Virgin, and Muddy; as well as Las Vegas Wash, which is now perennial because of discharges from municipal wastewater treatment plants (Covay and Leiker, 1998) and urban stormwater runoff. As the population within the Las Vegas Valley began to increase in the 1940s, the treated effluent volume also has increased and in 1993 it constituted about 96 percent of the annual discharge of Las Vegas Wash (Bevans and others, 1996). The mean flow of Las Vegas Wash into Las Vegas Bay from 1992 to 1998 was about 490,000 m3/d (Preissler and others, 1999) and in 2001 increased to 606,000 m3/d (U.S. Bureau of Reclamation, 2001). The nutrient concentration in most areas of the lake is low, but wastewater discharged into Las Vegas Bay has caused an increased level of nutrients and primary productivity (aquatic plant and algal production) in this area of the lake (LaBounty and Horn, 1997). A byproduct of this increase in productivity has been the establishment of an important recreational fishery in Las Vegas Bay. However, concentrations of chlorophyll a (a measure of algal biomass) have also increased (LaBounty and Horn, 1997). In the spring of 2001, parts of Lake Mead experienced massive algal blooms. In addition to nutrient loading by wastewater, the presence of numerous synthetic chemicals in water, bottom sediments, and in fish tissue also has been reported (Bevans and others, 1996). Synthetic chemicals discharging into Las Vegas Bay and Lake Mead (fig. 1) originate from several sources that include surplus residential-irrigation water runoff, stormwater runoff, subsurface inflow, and tertiary treated sewage effluent discharging from three sewage-treatment plants. Chemicals detected in Las Vegas Wash and Bay environments include polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (including DDT and DDE), and 'emerging contaminants' such as fragrances/musks, flame retardants, triclosan and its breakdown products, personal care products, and pharmaceuticals (Bevans and others, 1996; Boyd and Furlong, 2002; Leiker and others, in press). Many of these compounds are able to interact with the endocrine system of animals and potentially cause reproductive impacts. The National Park Service (NPS) manages Lake Mead National Recreation Area (LMNRA) with about 8 million yearly visitors including 500,000 anglers drawn to its world-class recreational fishery. The U.S. Fish and Wildlife Service (FWS) provides management for the federally designated, endangered razorback sucker (Xyrauchen texanus) and for more than 180 species of migratory birds that utilize LMNRA surface waters. These multiple uses of surface water in the area demonstrate their vital importance to the LMNRA as well as the need to maintain the quality of water at levels that are adequate for these uses.

Fact Sheet↗
USGS2010

Sediment contamination of residential streams in the metropolitan Kansas City area, USA: Part II. whole-sediment toxicity to the amphipod hyalella azteca

This is the second part of a study that evaluates the influence of nonpoint sources on the sediment quality of five adjacent streams within the metropolitan Kansas City area, central United States. Physical, chemical, and toxicity data (Hyalella azteca 28-day whole-sediment toxicity test) for 29 samples collected in 2003 were used for this evaluation, and the potential causes for the toxic effects were explored. The sediments exhibited a low to moderate toxicity, with five samples identified as toxic to H. azteca. Metals did not likely cause the toxicity based on low concentrations of metals in the pore water and elevated concentrations of acid volatile sulfide in the sediments. Although individual polycyclic aromatic hydrocarbons (PAHs) frequently exceeded effect-based sediment quality guidelines [probable effect concentrations (PECs)], only four of the samples had a PEC quotient (PEC-Q) for total PAHs over 1.0 and only one of these four samples was identified as toxic. For the mean PEC-Q for organochlorine compounds (chlordane, dieldrin, sum DDEs), 4 of the 12 samples with a mean PEC-Q above 1.0 were toxic and 4 of the 8 samples with a mean PEC-Q above 3.0 were toxic. Additionally, four of eight samples were toxic, with a mean PEC-Q above 1.0 based on metals, PAHs, polychlorinated biphenyls (PCBs), and organochlorine pesticides. The increase in the incidence of toxicity with the increase in the mean PEC-Q based on organochlorine pesticides or based on metals, PAHs, PCBs, and organochlorine pesticides suggests that organochlorine pesticides might have contributed to the observed toxicity and that the use of a mean PEC-Q, rather than PEC-Qs for individual compounds, might be more informative in predicting toxic effects. Our study shows that stream sediments subject to predominant nonpoint sources contamination can be toxic and that many factors, including analysis of a full suite of PAHs and pesticides of both past and present urban applications and the origins of these organic compounds, are important to identify the causes of toxicity.

Kansas, Missouri↗
USGS2010

Effects of urbanization on stream ecosystems along an agriculture-to-urban land-use gradient, Milwaukee to Green Bay, Wisconsin, 2003-2004

In 2003 and 2004, 30 streams near Milwaukee and Green Bay, Wisconsin, were part of a national study by the U.S. Geological Survey to assess urbanization effects on physical, chemical, and biological characteristics along an agriculture-to-urban land-use gradient. A geographic information system was used to characterize natural landscape features that define the environmental setting and the degree of urbanization within each stream watershed. A combination of land cover, socioeconomic, and infrastructure variables were integrated into a multi-metric urban intensity index, scaled from 0 to 100, and assigned to each stream site to identify a gradient of urbanization within relatively homogeneous environmental settings. The 35 variables used to develop the final urban intensity index characterized the degree of urbanization and included road infrastructure (road area and road traffic index), 100-meter riparian land cover (percentage of impervious surface, shrubland, and agriculture), watershed land cover (percentage of impervious surface, developed/urban land, shrubland, and agriculture), and 26 socioeconomic variables (U.S. Census Bureau, 2001). Characteristics examined as part of this study included: habitat, hydrology, stream temperature, water chemistry (chloride, sulfate, nutrients, dissolved and particulate organic and inorganic carbon, pesticides, and suspended sediment), benthic algae, benthic invertebrates, and fish. Semipermeable membrane devices (SPMDs) were used to assess the potential for bioconcentration of hydrophobic organic contaminants (specifically polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine and pyrethroid insecticides) in biological membranes, such as the gills of fish. Physical habitat measurements reflective of channel enlargement, including bankfull channel size and bank erosion, increased with increasing urbanization within the watershed. In this study, percentage of riffles and streambed substrate size were more strongly related to local geologic setting, slope, watershed topography, and river-engineering practices than to urbanization. Historical local river-engineering features such as channelization, bank stabilization, and grade controls may have confounded relations among habitat characteristics and urbanization. A number of hydrologic-condition metrics (including flashiness and duration of high flow during pre- or post-ice periods) showed strong relations to the urban intensity index. Hydrologic-condition metrics cannot be used alone to predict habitat or geomorphic change. Chloride and SPMD measures of potential toxicity and polycyclic aromatic hydrocarbon concentrations showed the strongest positive correlations to urbanization including increases in road infrastructure, percentage of impervious surface in the watershed, urban land cover, and land-distribution related to urban land cover. This suggests that automobiles and the infrastructure required to support automobiles are a significant source of these compounds in this study area. Chloride in spring and summer showed a significant positive correlation with the urban intensity index; concentrations increased with increasing road infrastructure, urban land cover, and a number of landscape variables related to urbanization. Spring concentrations of sulfate, prometon, and diazinon correlated to fewer urban characteristics than chloride, including increases in road infrastructure, percentage of impervious surface, and urban land cover. Changes in biological communities correlated to the urban intensity index or individual urban-associated variables. Decreased percentages of pollution-sensitive diatoms and diatoms requiring high dissolved-oxygen saturation correlated to increases in the percentage of developed urban land, total impervious surface, stream flashiness, population density, road-area density, and decreases in the percentage of wetland in the watershed. Invertebrate taxa richness and Coleop

Scientific Investigations Report↗
USGS2012

Contaminants in stream sediments from seven United States metropolitan areas: part II—sediment toxicity to the amphipod Hyalella azteca and the midge Chironomus dilutus

Relationships between sediment toxicity and sediment chemistry were evaluated for 98 samples collected from seven metropolitan study areas across the United States. Sediment-toxicity tests were conducted with the amphipod Hyalella azteca (28 day exposures) and with the midge Chironomus dilutus (10 day exposures). Overall, 33 % of the samples were toxic to amphipods and 12 % of the samples were toxic to midge based on comparisons with reference conditions within each study area. Significant correlations were observed between toxicity end points and sediment concentrations of trace elements, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), or organochlorine (OC) pesticides; however, these correlations were typically weak, and contaminant concentrations were usually below sediment-toxicity thresholds. Concentrations of the pyrethroid bifenthrin exceeded an estimated threshold of 0.49 ng/g (at 1 % total organic carbon) in 14 % of the samples. Of the samples that exceeded this bifenthrin toxicity threshold, 79 % were toxic to amphipods compared with 25 % toxicity for the samples below this threshold. Application of mean probable effect concentration quotients (PECQs) based on measures of groups of contaminants (trace elements, total PAHs, total PCBs,OCpesticides, and pyrethroid pesticides [bifenthrin in particular]) improved the correct classification of samples as toxic or not toxic to amphipods compared with measures of individual groups of contaminants. Sediments are a repository for many contaminants released into surface waters. Because of this, organisms inhabiting sediments may be exposed to a wide range of contaminants (United States Environmental Protection Agency (USEPA) United States Environmental Protection Agency 2000; American Society for Testing and Materials [ASTM] American Society for Testing and Materials International 2012). Contaminants of potential concern in sediments typically include trace elements (metals), organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs; Ingersoll et al. 2001). In 2000, the USEPA began to restrict the use of organophosphate pesticides, such as diazinon and chlorpyrifos (Spurlock and Lee 2008). These restrictions have led to increased use of pyrethroid pesticides, which have widespread applications in both agricultural and urban environments (Kuivila et al. 2012). Pyrethroids are hydrophobic compounds that have been observed to accumulate in sediments (Laskowski 2002). Toxicity of pyrethroids in field-collected sediment from small urban streams (Weston et al. 2005; Holmes et al. 2008; Ding et al. 2010; Domagalski et al. 2010) or with pyrethroids spiked into sediment (Amweg et al. 2006; Hintzen et al. 2009) have been evaluated primarily in 10 day lethality tests conducted with the amphipod Hyalella azteca . However, the sublethal effects in long-term exposures to pyrethroids in sediment have not been evaluated, and the distribution of pyrethroids sediments has not typically been evaluated in wadeable streams (Gilliom et al. 2006). This article is the second in a series that describe the results of a study of the distribution and toxicity of pyrethroids and other co-occurring trace elements and organic contaminants (PCBs, PAHs, OC pesticides) in stream sediments from 7 metropolitan areas across the United States (Moran et al. 2012). The study evaluated 98 sediment samples collected from streams ranging from undeveloped to highly urban and differs from previous studies by sampling larger wadeable streams and avoiding point sources (such as storm drains) and other inflows (Gilliom et al. 2006). Part 1 of the series characterizes sediment contaminants in relation to urbanization and other factors in the 7 metropolitan study areas (Nowell et al. 2012). Part 2 (this article) evaluates relationships between sediment chemistry and sediment toxicity in 28 day whole-sediment exposures conducted with the amphipod H. azteca and in 10 day whole-sediment exposure conducted with the midge Chironomus dilutus (USEPA United States Environmental Protection Agency 2000; ASTM American Society for Testing and Materials International 2012). Toxicity end points evaluated in the amphipod and midge exposures included the effects of these field-collected sediments on survival, weight, or biomass of the test organisms.

Georgia;Massachusetts;Texas;Colorado;Wisconsin;Uta↗