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David A. Alvarez

Publications and source records attributed to David A. Alvarez.

66 records · Page 4Linked to original sources
USGS2011

Water-quality monitoring for a pilot piling removal field evaluation, Coal Creek Slough, Washington, 2008-09

Significant Findings Water and sediment quality monitoring was conducted before and after the removal of a piling field located in Coal Creek Slough near Longview, Washington. Passive chemical samplers and continuous water-quality monitoring instruments were deployed at the piling removal site, Coal Creek Slough Site 1 (CCS1), and at a comparison site, Coal Creek Slough Site 2 (CCS2), before (2008) and after (2009) piling removal. Surface and subsurface (core) sediment samples were collected before and after piling removal and were analyzed for grain size, organic carbon content, and chemicals of concern. Significant findings from this study include: * Phenanthrene was the only compound detected in wood piling samples analyzed for a large suite of semivolatile organic compounds and polycyclic aromatic hydrocarbons (PAHs). Metals potentially associated with wood treatment were detected in the wood piling samples at low concentrations. * Organic carbon was slightly lower in core samples from CCS1 in pre-removal (2008) and post-removal (2009) samples than in surface samples from both sites in both years. * Grain-size class distributions were relatively uniform between sites and years. * Thirty-four out of 110 chemicals of concern were detected in sediments. Eight of those detected were anthropogenic waste indicator (AWI) compounds, 18 were PAHs, 4 were sterols, and 4 were metals potentially associated with wood treatment. * Nearly all reported concentrations of chemicals of concern in sediments are qualified as estimates, primarily due to interferences in extracts resulting from complex sample matrices. Indole, perylene, and fluoranthene are reported without qualification for some of the samples, and the metals are reported without qualification for all samples. * The highest frequency of detection of chemicals of concern was seen in the pre-removal surface samples at both sites. * AWI compounds were detected less frequently and at lower concentrations during the post-removal sampling compared to the pre-removal sampling. * Several PAHs were detected at relatively high concentrations in core samples, likely indicating historical sources. * Most commonly detected PAHs in sediments were 2,6-dimethylnaphthalene, fluoranthene, perylene, and pyrene. * Most commonly detected AWIs in sediments were 3-methyl-1h-indole (skatol), acetophenone, indole, phenol, and paracresol. * Sedimentary concentrations of perylene exceeded available sediment quality guidelines. Perylene is widespread in the environment and has large potential natural sources in addition to its anthropogenic sources. * Concentrations of metals did not exceed sediment quality guidelines. * Multiple organochlorine pesticides, both banned and currently used, were detected at each site using passive samplers. * Commonly detected pesticides included hexachlorobenzene, pentachloroanisole (a degradation product of pentachlorophenol), diazinon, cis-chlordane, endosulfan, DDD, and endosulfan sulfate. * PBDE concentrations detected in passive sampler extracts were less than the method detection limit at all sites with the exception of PBDE-99, detected at a concentration less than the reporting limit. * The fragrance galaxolide was detected at a concentration greater than the method detection limit. * Common PAHs, such as phenanthrene, fluoranthene, and pyrene, were detected in every passive sampler. * Dissolved oxygen concentration was slightly higher at site CCS1 compared to site CCS2 in both years. * Overall, there was no systematic increase in chemicals of concern at the restoration site during post-removal monitoring compared to conditions during pre-removal monitoring. Any immediate, short-duration effects of piling removal on water quality could not be determined because monitoring was not conducted during the removal.

Open-File Report↗
USGS2010

Biological water-quality assessment of selected streams in the Milwaukee Metropolitan Sewerage District Planning Area of Wisconsin, 2007

Changes in the water quality of stream ecosystems in an urban area may manifest in conspicuous ways, such as in murky or smelly streamwater, or in less conspicuous ways, such as fewer native or pollution-sensitive organisms. In 2004, and again in 2007, the U.S. Geological Survey sampled stream organisms—algae, invertebrates, and fish—in 14 Milwaukee area streams to assess water quality as part of the ongoing Milwaukee Metropolitan Sewerage District (MMSD) Corridor Study. In addition, passive-sampling devices (SPMDs, “semipermeable membrane devices”) were deployed at a subset of sites in order to evaluate the potential exposure of stream organisms to certain toxic chemicals. Results of the 2007 sampling effort are the focus of this report. Results of sampling from 2007 are compared with results from 2004. The water quality of sampled streams was assessed by evaluating biological-assemblage data, metrics computed from assemblage data, and an aggregate bioassessment ranking method that combined data for algae, invertebrates, and fish. These data contain information about the abundance (number) of different species in each group of stream organisms and the balance between species that can or cannot tolerate polluted or disturbed conditions. In 2007, the highest numbers of algal, invertebrate, and fish species were found at the Milwaukee River at Milwaukee, the largest sampled site. Algal results indicated water quality concerns at 10 of the 14 sampled sites due to the occurrence of nuisance algae or low percentages of pollution-sensitive algae. When compared to 2004, total algal biovolume was higher in 2007 at 12 of 14 sites, due mostly to more nuisance green algae from unknown causes. Results of several metrics, including the Hilsenhoff Biotic Index (HBI-10), suggest that invertebrate assemblages in the Little Menomonee River, Underwood Creek, and Honey Creek were poorer quality in 2007 compared to 2004. Six sites received “very poor” quality ratings for fish in 2007, mostly because inadequate numbers of fish were collected at five sites to allow computation of an Index of Biotic Integrity (IBI); this resulted in three additional sites receiving “very poor” ratings compared to 2004. Some signs of potential improvement in the fish assemblage were evident at Lincoln Creek, possibly reflecting delayed effects of the restoration of stream habitat, completed in 2002; however, algae and invertebrates did not show signs of improvement. Aggregate bioassessment rankings across all groups of organisms for 2004 and 2007 indicated that water quality at the two Milwaukee River main stem sites (at Milwaukee and near Cedarburg), Jewel Creek, and the Menomonee River at Menomonee Falls was the least-degraded among all sampled sites. Rankings for Oak Creek and Little Menomonee suggested water quality was worse in 2007 compared to 2004 and placed these two sites together with Kinnickinnic River and Underwood Creek, two concrete-line sites, indicating the most-degraded water quality among all sampled sites. The aggregate ranking for Lincoln Creek in 2007 would have placed it in the most-degraded category but for the positive influence of the fish ranking when compared to poor algal and invertebrate rankings. Potential toxicity due to certain manmade chemicals, such as polycyclic aromatic hydrocarbons (PAHs), was found at all six sites where SPMDs were deployed. As was found in 2004, the highest potential toxicity in 2007 was observed at Lincoln Creek where chemical screening in 2007 also showed the highest total PAHs of all six sites; however, potential toxicity at Little Menomonee River, Honey Creek, and Kinnickinnic River was relatively high compared to Milwaukee River near Cedarburg. Although toxicity and chemical results in 2007 did not agree with aggregate rankings for Lincoln Creek because of fish, nor for Honey Creek, the results did agree with aggregate rankings at four of the six sites. In addition to toxicological and chemical influences, the more urbanized sites have high percentages of impervious surface area, resulting in frequent high stream flows that can adversely affect algal, invertebrate, and fish assemblages. Assessments of the ecological status of different groups of organisms and of potential chemical and physical stressors to organisms are important tools in evaluating streamwater quality.

Wisconsin↗
USGS2010

Guidelines for the use of the semipermeable membrane device (SPMD) and the polar organic chemical integrative sampler (POCIS) in environmental monitoring studies

The success of an environmental monitoring study using passive samplers, or any sampling method, begins in the office or laboratory. Regardless of the specific methods used, the general steps include the formulation of a sampling plan, training of personnel, performing the field (sampling) work, processing the collected samples to recover chemicals of interest, analysis of the enriched extracts, and interpretation of the data. Each of these areas will be discussed in the following sections with emphasis on specific considerations with the use of passive samplers. Water is an extremely heterogeneous matrix both spatially and temporally (Keith, 1991). The mixing and distribution of dissolved organic chemicals in a water body are controlled by the hydrodynamics of the water, the sorption partition coefficients of the chemicals, and the amount of organic matter (suspended sediments, colloids, and dissolved organic carbon) present. In lakes and oceans, stratification because of changes in temperature, water movement, and water composition can occur resulting in dramatic changes in chemical concentrations with depth (Keith, 1991). Additional complications related to episodic events, such as surface runoff, spills, and other point source contamination, can result in isolated or short-lived pulses of contaminants in the water. The application of passive sampling technologies for the monitoring of legacy and emerging organic chemicals in the environment is becoming widely accepted worldwide. The primary use of passive sampling methods for environmental studies is in the area of surface-water monitoring; however, these techniques have been applied to air and groundwater monitoring studies. Although these samplers have no mechanical or moving parts, electrical or fuel needs which require regular monitoring, there are still considerations that need to be understood in order to have a successful study. Two of the most commonly used passive samplers for organic contaminants are the semipermeable membrane device (SPMD) and the polar organic chemical integrative sampler (POCIS). The tips given in this document focus on these two samplers but are applicable to most types of passive sampling devices. The information in this guide is heavily weighted towards the sampling of water; however, information specific to the use of SPMDs for air sampling will also be covered.

Techniques and Methods↗
USGS2009

Sources and distribution of organic compounds using passive samplers in Lake Mead National Recreation Area, Nevada and Arizona, and their implications for potential effects on aquatic biota.

Th e delineation of lateral and vertical gradients of organic contaminants in lakes is hampered by low concentrations and nondetection of many organic compounds in water. Passive samplers (semipermeable membrane devices [SPMDs] and polar organic chemical integrative samplers [POCIS]) are well suited for assessing gradients because they can detect synthetic organic compounds (SOCs) at pg L-1 concentrations. Semi-permeable membrane devices and POCIS were deployed in Lake Mead, at two sites in Las Vegas Wash, at four sites across Lake Mead, and in the Colorado River downstream from Hoover Dam. Concentrations of hydrophobic SOCs were highest in Las Vegas Wash downstream from waste water and urban inputs and at 8 m depth in Las Vegas Bay (LVB) where Las Vegas Wash enters Lake Mead. Th e distribution of hydrophobic SOCs showed a lateral distribution across 10 km of Lake Mead from LVB to Boulder Basin. To assess possible vertical gradients of SOCs, SPMDs were deployed at 4-m intervals in 18 m of water in LVB. Fragrances and legacy SOCs were found at the greatest concentrations at the deepest depth. Th e vertical gradient of SOCs indicated that contaminants were generally confi ned to within 6 m of the lake bottom during the deployment interval. The high SOC concentrations, warmer water temperatures, and higher total dissolved solids concentrations at depth are indicative of a plume of Las Vegas Wash water moving along the lake bottom. Th e lateral and vertical distribution of SOCs is discussed in the context of other studies that have shown impaired health of fish exposed to SOCs.

Journal of Environmental Quality↗
USGS2009

Effects of wastewater discharges on endocrine and reproductive function of Western Mosquitofish (Gambusia spp.) and implications for the threatened Santa Ana Sucker (Catostomus santaanae)

The Santa Ana River (SAR) in southern California is impacted by effluents from wastewater treatment plants (WWTP), which are sources of organic wastewater compounds (OWCs) and urban runoff. The Santa Ana River is one of only three river basins supporting native populations of the federally listed Santa Ana sucker ( Catostomus santaanae ) at the time the fish was included on the list 2000. In 2004 and 2005, a U.S. Geological Survey and U.S. Fish and Wildlife Service study was undertaken to determine if the threatened Santa Ana sucker was potentially exposed to OWCs and endocrine disrupting compounds (EDCs) in the SAR by using the western mosquitofish ( Gambusia affinis ) as a surrogate fish model. Four Santa Ana River sites were chosen along a gradient of proximity to WWTP effluents: (1) a point source of tertiary treated wastewater effluent (TTWE), (2) Rialto Drain (just below a WWTP), (3) Prado Dam (11 kilometers [km] below WWTPs), and (4) Sunnyslope Creek (no WWTP but having urban runoff influence). A reference site having no WWTPs or urban runoff, Thousand Palms, was also sampled. Chemical analyses of passive sampler extracts results showed that 15 OWCs and EDCs were detected in water from the Santa Ana River sites. Many of these compounds contributed to activity from an estrogenic in-vitro assay that showed a significant potential for impacting endocrine and reproductive systems compared to the 25 organochlorine compounds detected in aquatic biota. The site showing compounds having highest influence on sex steroid hormone activities was the point source for TTWE. Sex steroid hormone levels, secondary sex characteristics, organosomatic indices, and sperm quality parameters indicated impairment of endocrine and reproductive function of male western mosquitofish in the Santa Ana River. Exposure to EDCs and consequent impairment in mosquitofish followed the gradient of proximity to WWTP effluents, where the most significant effects were found at TTWE point source and Rialto Drain, followed by Prado Dam and Sunnyslope Creek. Each of these sites is suitable habitat for the Santa Ana sucker, especially Sunnyslope Creek and Rialto Drain where juveniles reside. Various OWCs and EDCs were detected at each Santa Ana River site, although one specific compound or group of compounds could not be singled out as a causative factor. Di (2-ethylhexyl) phthalate was strongly negatively correlated with testosterone in male mosquitofish. One group of potent environmental estrogens that likely contributed to endocrine and reproductive impairment are the natural and synthetic estrogen hormones, especially ethinyl estradiol; however, this compound was not targeted in these investigations. The multiple lines of evidence for impaired reproductive and endocrine function in western mosquitofish due to OWCs and EDCs from the Santa Ana River can be used to identify potential problems for the Santa Ana sucker inhabiting the same and nearby sites.

California↗
USGS2009

Evaluation of passive samplers for long-term monitoring of organic compounds in the untreated drinking water supply for the city of Eugene, Oregon, September–October 2007

Two types of passive samplers, polar organic chemical integrative samplers (POCIS) and semipermeable membrane devices (SPMDs), were deployed at three sites in the McKenzie River basin during September-October 2007. The McKenzie River is the source of drinking water for the city of Eugene, Oregon, and the work presented here was designed to evaluate the use of POCIS and SMPDs as part of a long-term monitoring plan for the river. Various compounds were detected in extracts from the POCIS and SPMDs, indicating that some compounds of concern are present in the McKenzie River basin, including the intake for the drinking water plant. However, most concentrations were near the quantitation limits of the analytical methods used - generally at subnanogram per liter concentrations - and would not have been detectable with conventional water sampling and analysis methods. These results indicate that both POCIS and SPMDs are well suited to monitor organic compounds in the McKenzie River basin.

Oregon↗
USGS2008

Investigation of organic chemicals potentially responsible for mortality and intersex in fish of the North Fork of the Shenandoah River, Virginia, during Spring of 2007

Declining fish health, fish exhibiting external lesions, incidences of intersex, and death, have been observed recently within the Potomac River basin. The basin receives surface runoff and direct inputs from agricultural, industrial, and other human activities. Two locations on the North Fork of the Shenandoah River were selected for study in an attempt to identify chemicals that may have contributed to the declining fish health. Two passive sampling devices, semipermeable membrane devices (SPMDs) and polar organic chemical integrative samplers (POCIS), were deployed during consecutive two-month periods during the spring and early summer of 2007 to measure select organic contaminants to which fish may have been exposed. This study determined that concentrations of persistent hydrophobic contaminants, such as polycyclic aromatic hydrocarbons (< picograms per liter), legacy pesticides (<10 picograms per liter), and polychlorinated biphenyls (<280 picograms per liter) were low and indicative of a largely agricultural area. Atrazine and simazine were the most commonly detected pesticides. Atrazine concentrations ranged from 68 to 170 nanograms per liter for the March to April study period and 320 to 650 nanograms per liter for the April to June study period. Few chemicals characteristic of wastewater treatment plant effluent or septic tank discharges were identified. In contrast, para-cresol, N,N-diethyltoluamide, and caffeine commonly were detected. Prescription pharmaceuticals including carbamazepine, venlafaxine, and 17a-ethynylestradiol were at low concentrations. Extracts from the passive samplers also were screened for the presence of estrogenic chemicals using the yeast estrogen screen. An estrogenic response was observed in POCIS samples from both sites, whereas SPMD samples exhibited little to no estrogenicity. This indicates that the chemicals producing the estrogenic response have a greater water solubility and are, therefore, less likely to bioaccumulate in fatty tissues of organisms.

Virginia↗
USGS2008

Reconnaissance of persistent and emerging contaminants in the Shenandoah and James River Basins, Virginia, during Spring of 2007

Fish exhibiting external lesions, incidences of intersex, and death have recently been observed in the Shenandoah and James River Basins. These basins are characterized by widespread agriculture (intensive in some areas), several major industrial discharges, numerous sewage treatment plant discharges, and urban, transportation, and residential growth that has increased rapidly in recent years. Nine locations in the Shenandoah River Basin, Virginia, and two in the James River Basin, Virginia, were selected for study in an attempt to identify chemicals that may have contributed to the declining fish health. Two passive sampling devices, semipermeable membrane devices (SPMDs) and polar organic chemical integrative samplers (POCIS), were deployed during the spring and early summer of 2007 to measure select organic contaminants to which fish may have been exposed. This study determined that concentrations of persistent hydrophobic contaminants, such as polycyclic aromatic hydrocarbons (<17,000 picograms per liter), legacy pesticides (<510 picograms per liter), and polychlorinated biphenyls (<1,600 picograms per liter) were generally low and indicative of a largely agricultural area. Chlorpyrifos, endosulfan, and lindane were the most commonly detected chlorinated pesticides. Atrazine, which was detected at concentrations much greater than other pesticides associated with agricultural use, ranged from <0.18 to 430 nanograms per liter during the deployment period. Few chemicals characteristic of wastewater treatment plant effluent or septic tank discharges were detected. The fragrance components, galaxolide, indole, and tonalide, were the predominant waste indicator chemicals detected. Caffeine, the caffeine metabolite 1,7-dimethylxanthine, the nicotine metabolite cotinine, and the prescription pharmaceuticals carbamazepine, venlafaxine, and trimethoprim were detected at several sites. Natural and synthetic hormones were detected at a few sites with 17α-ethynylestradiol concentrations esimated up to 8.1 nanograms per liter. Screening of the POCIS extracts for estrogenic chemicals by using the yeast estrogen screen revealed estrogenicity similar to levels reported for rural areas with minor effect from wastewater effluents.

Virginia↗
USGS2007

Feasibility of a simple laboratory approach for determining temperature influence on SPMD–air partition coefficients of selected compounds

Semipermeable membrane devices (SPMDs) are a widely used passive sampling methodology for both waterborne and airborne hydrophobic organic contaminants. The exchange kinetics and partition coefficients of an analyte in a SPMD are mediated by its physicochemical properties and certain environmental conditions. Controlled laboratory experiments are used for determining the SPMD&ndash;air ( K sa 's) partition coefficients and the exchange kinetics of organic vapors. This study focused on determining a simple approach for measuring equilibrium K sa 's for naphthalene (Naph), o -chlorophenol ( o -CPh) and p -dichlorobenzene ( p -DCB) over a wide range of temperatures. SPMDs were exposed to test chemical vapors in small, gas-tight chambers at four different temperatures (&minus;16, &minus;4, 22 and 40 &deg;C). The exposure times ranged from 6 h to 28 d depending on test temperature. K sa 's or non-equilibrium concentrations in SPMDs were determined for all compounds, temperatures and exposure periods with the exception of Naph, which could not be quantified in SPMDs until 4 weeks at the &minus;16 &deg;C temperature. To perform this study the assumption of constant and saturated atmospheric concentrations in test chambers was made. It could influence the results, which suggest that flow through experimental system and performance reference compounds should be used for SPMD calibration.

Atmospheric Environment↗
USGS2007

Chapter 8 Tool for monitoring hydrophilic contaminants in water: polar organic chemical integrative sampler (POCIS)

The development of the polar organic chemical integrative sampler (POCIS) provides environmental scientists and policy makers a tool for assessing the presence and potential impacts of the hydrophilic component of these organic contaminants. The POCIS provides a means for determining the time-weighted average (TWA) concentrations of targeted chemicals that can be used in risk assessments to determine the biological impact of hydrophilic organic compounds (HpOCs) on the health of the impacted ecosystem. Field studies have shown that the POCIS has advantages over traditional sampling methods in sequestering and concentrating ultra-trace to trace levels of chemicals over time resulting in increased method sensitivity, ability to detect chemicals with a relatively short residence time or variable concentrations in the water, and simplicity in use. POCIS extracts can be tested using bioassays and can be used in organism dosing experiments for determining toxicological significance of the complex mixture of chemicals sampled. The POCIS has been successfully used worldwide under various field conditions ranging from stagnant ponds to shallow creeks to major river systems in both fresh and brackish water.

Comprehensive Analytical Chemistry↗