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1.
The lower 6 miles of the tidal Passaic River, part of the New York/New Jersey (NY/NJ) Harbor Estuary system, are contaminated with a variety of organic and inorganic chemicals as a result of more than 150 years of heavy industrialization and urbanization. The River's ecology is substantially degraded due to habitat removal/alteration, and the organisms that reside in or utilize the River are exposed to and bioaccumulate chemicals from sediments and food web interactions. We quantify in this study the extent and magnitude of chemical contamination in several fish species (representing a range of trophic levels) and blue crab (Callinectes sapidus). In addition, the concentration of several contaminants of concern are compared to concentrations in similar organisms from other areas of the NY/NJ Harbor Estuary, as well as available tissue-based toxicological effects benchmarks that are reported in the literature. The results suggest that a variety of contaminants are present at elevated levels in each of the species collected from the River. Several contaminants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), total DDT (2,2-bis[4-chlorophenyl]1,1-dichloroethene), copper, and mercury are present at average concentrations that exceed those from other waterways in the NY/NJ Harbor Estuary. However, the concentrations of contaminants in the River, with few exceptions do not exceed available toxic effects levels as reported in the literature for these or similar fish and crustaceans. This suggests that toxicological risks from bioaccumulative contaminants in the lower Passaic River are limited to select contaminants and species.  相似文献   

2.
It is suggested that dynamic mass balance models can provide valuable support information when sediment remediation activities, such as dredging, are contemplated. A model with sufficient credibility and accuracy can be used to compare and contrast the results of various remediation actions and the effect of natural remediation processes. A food web model can also be included. The information provided by the model can be summarized in periodic (e.g. annual) “Report Cards” documenting the status of the contaminated system during and after the remediation process. Time plots of relevant properties of the system, such as contaminant masses, concentrations and levels in water, sediment and biota, can convey the essential information required for decision-making. This approach is illustrated by applying it with screening level accuracy to the remediation activities currently being undertaken in the St. Clair River, which flows from Lake Huron to Lake St. Clair near Sarnia, Ontario, Canada. The effects of dredging to reduce concentrations of hexachlorobenzene in sediment, water and biota are explored.  相似文献   

3.
Managers of New York and New Jersey Harbor dredging projects are developing strategies to dispose and manage the large volumes of sediment that must be dredged to maintain passable waterways. The various management alternatives include aquatic containment facilities, upland containment, and treatment with beneficial reuse. An important consideration in the selection of an appropriate alternative is the evaluation of potential risks to ecological and human receptors. This study presents a framework for a screening-level ecological and human health risk assessment that compares risks associated with management alternatives for contaminated dredged materials. The major objectives of the work were to identify exposure routes that show the potential for risk and develop a framework that can be used to compare relative potential risks among eight management alternatives. Managers can use this framework to: ? identify characteristics of the placement/treatment alternatives that contribute to potential risk, ? choose one alternative over another for sediments with high concentrations of contaminants, ? implement controls that mitigate risk, or ? identify the need for a more comprehensive site-specific risk assessment.  相似文献   

4.
A rule-based, weight-of-evidence approach for assessing contaminated sediment on a site-by-site basis in the Laurentian Great Lakes is described. Information from four lines of evidence—surficial sediment chemistry, laboratory toxicity, invertebrate community structure and invertebrate tissue biomagnification—is integrated within each line to produce a pass (‘?’) or fail (‘+’) conclusion, then combined across lines resulting in one of 16 outcome scenarios. For each scenario, the current status of the site, interpretation, and management recommendations are given. Management recommendation(s) can range from no action to risk management required (9 of the 16 scenarios). Within each line of evidence, the strength of each response can also be ranked (e.g., score of 1 to 4), providing managers with more information to aid decision options. Other issues that influence scientific management recommendations include site stability, subsurface contamination and spatial extent of effects. The decision framework is intended to be transparent, comprehensive (incorporating exposure, effect, weight-of-evidence, and risk), and minimally uncertain.  相似文献   

5.
Current environmental challenges involve complex assessment and analysis of tradeoffs among differing criteria, expectations, and levels of certainty. Using multi-criteria decision analysis in combination with comparative risk assessment, a systematic and transparent framework can be created to integrate different types and sources of decision-relevant information. Although examples of decision analysis abound in the literature and academic efforts, its use within the practice of risk assessment and environmental management is still being established. This article provides an example of the use of decision analysis study that builds on a previous screening-level, comparative risk assessment of contaminated sediment from the New York/New Jersey harbor area. Using multi-criteria decision analysis, we explored the effect of different criteria weights, utility functions, and cost estimates on the ranking of seven contaminated sediment management alternatives. Values used in weighting decision criteria were surveyed from two interaction sessions with sediment management professionals.  相似文献   

6.
Monitoring environmental policy progress often focuses on contaminant concentrations while policy goals address health. To bridge this gap, we developed policy evaluation case studies applying risk assessment methods to explore population health risks of chemical exposures before and after policy implementation. Beginning in the 1970s the New Jersey Department of Environmental Protection provided some of the United States' first data on contaminants including trichloroethylene in drinking water and polychlorinated biphenyls (PCBs) in fish. These data provide a unique opportunity to evaluate environmental policies. The 1979 PCB manufacturing ban succeeded in reducing exposure and risk, but the persistence of these compounds in local fish requires continued state and local consumption advisories. The positive impact of drinking water standards for trichloroethylene was reflected in declining detection in public water supplies from the late 1970s to 2005, although maximum concentrations in a small percentage of supplies remain above standards. Our case studies show success and progress, and the need for multiple policies in combination when conditions warrant. Tracking specific policies and contaminants using risk assessment methods can be a valuable tool for policy evaluation and can foster population-based environmental health research. Pollution prevention policies are warranted for chemicals that persist in the environment.  相似文献   

7.
A new model of bioturbation has been developed to describe short term sediment reworking induced by macrobenthic communities. The design of the model had to consider the mixing processes, firstly, at the organism level, and secondly, at community level. This paper describes the mixing mode of the four types of bioturbators defined by the authors: the biodiffusors, the upward-conveyors, the downward-conveyors and the regenerators. The mathematical formulation of these sub-models consists of ordinary differential equations. They take into account the size of the bioturbated zone, the output fluxes to the water column, tracer decay, physical mixing due to local currents and the type and intensity of the bioturbation processes. These sub-models make it possible to describe correctly the mixing events that have occurred in cores with each type of bioturbator. They also provide the basis for general bioturbation model, that will take into account the respective degrees of involvement of (i) the different bioturbation processes and their characteristics, (ii) the interference between the different processes, and (iii) make possible to predict the particle reworking in order to include it in studies of organic matter in early diagenesis. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

8.
The objectives of this study were to (1) determine if historical exceedences of oil and grease concentrations above the limits allowed in the National Pollution Elimination Discharge System permit for the wastewater treatment facility of Motiva Enterprises LLC Refinery, Delaware City, Delaware, could be determined from the sedimentary records of the Delaware River and, if so, (2) were the concentrations of contaminants high enough to be toxic to aquatic biota. Eighty-four surficial sediment samples, both within and outside the influence of the Refinery's discharge plume, were initially evaluated for their appropriateness for coring. Seven stations were ultimately selected for the historical core studies. Based on sediment type, radionuclide (Pb-210, Cs-137 and Be-7) geochronologies, and proximity of the cores to the Refinery, two cores were selected for more detailed polycyclic aromatic hydrocarbon (PAH) analyses. The rapid accumulation area of one core (located in the near-field of the discharge plume) had maximum total PAH (TPAH) concentration peaks at depths of 4 cm (1997; 3100 ng/g dw) and at 8.5–9 cm (1993; 3200 ng/g dw); the second core (located on the far-field periphery of the plume) had a maximum TPAH peak at 6.5 cm (1997; 3200 ng/g dw). In all cases, the maximum TPAH concentrations were below NOAA's Effects Range-Low concentration of 4022 ng/g dw for sediment biota toxicity. A chemical fingerprinting analysis of the PAHs in the two cores showed, however, that the PAHs present in the cores were predominantly pyrogenic PAHs consistent with Delaware River background PAHs. The core results are consistent with historic sediment PAH inputs in an industrial river system. PAH from the Refinery, if present, exist as a non-detectable increment to a high PAH baseline from many sources.  相似文献   

9.
A sediment quality index (SQI) based on the Canadian Water Quality Index was developed and applied to the assessment of sediment quality in two Great Lakes Areas Of Concern where metals are the primary contaminants of potential concern, Peninsula Harbour (Lake Superior) and Collingwood Harbour (Lake Huron). The SQI was calculated according to an equation incorporating two elements; scope—the number of variables that do not meet guideline objectives; and, amplitude—the magnitude by which variables exceed guideline objectives. Categorizations of sediment quality were developed based on SQI scores. The robustness of the SQI was evaluated through comparison of the relative rankings of sediment quality in the two test areas with results obtained from principle components analysis (PCA) incorporating reference sites, and calculations of hazard quotients (HQs). Trends and rankings in sediment quality determined by the SQI were similar to those calculated using PCA at both test areas. The HQs also appeared to be good indicators of sediment quality. Both the SQI and HQ methods are based on existing Sediment Quality Guidelines, but the SQI had the added benefit of allowing straightforward integration of multiple contaminants. The SQI and PCA analyses appeared complementary in that the SQI incorporated information on the number of variables exceeding guideline values and the degree to which these guidelines were exceeded. The PCA allowed a simple check of the SQI by relating test conditions to regional background. It is recommended that this analysis be performed concurrently with SQI to ensure that non-anthropogenic sources of contaminants (metals in this case) are not considered as representing an anthropogenic hazard.  相似文献   

10.
This article was prepared prior to the author's employment by the U.S. Environmental Protection Agency and therefore does not necessarily represent agency policy. Sediments provide needed habitats to valued aquatic and marine resources and are therefore an integral and valuable component of any coastal ecosystem. Studies have found that multiple anthropogenic activities have been the primary cause of sediment contamination. There is continued evidence that contaminated sediments pose adverse impacts to biological resources even when overlying water quality is acceptable. Efforts in environmental protection should therefore incorporate sediment quality management strategies. Despite a growing awareness and interest in management of contaminated sediment, no established systematic and standardized national management program has been established in the U.S. The establishment of a national sediment policy in the U.S. would reinforce the importance of integrating sediment issues with different management objectives and reiterate the importance of protecting sediments as a natural resource. A national sediment policy could also guide and direct states in developing state sediment policies that reflect national objectives while integrating local concerns. This perspective identifies and defines issues and concerns raised by 13 states’ agency staff in managing contaminated sediments in the absence of a national policy. Recommendations are developed that address sociopolitical and scientific issues and concerns. The recommendations are integrated with stakeholder comments, state manager needs and the existing regulatory and institutional framework.  相似文献   

11.
The aerobic polyaromatic hydrocarbon (PAH) degrading microbial communities of two petroleum-impacted Spartina-dominated salt marshes in the New York/New Jersey Harbor were examined using a combination of microbiological, molecular and chemical techniques. Microbial isolation studies resulted in the identification of 48 aromatic hydrocarbon-degrading bacterial strains from both vegetated and non-vegetated marsh sediments. The majority of the isolates were from the genera Paenibacillus and Pseudomonas. Radiotracer studies using 14C-phenanthrene and 14C-pyrene were used to measure the PAH-mineralization activity in salt marsh sediments. The results suggested a trend towards increased PAH mineralization in vegetated sediments relative to non-vegetated sediments. This trend was supported by the enumeration of PAH-degrading bacteria in non-vegetated and vegetated sediment using a Most Probable Numbers (MPN) technique, which demonstrated that PAH-degrading bacteria existed in non-vegetated and vegetated sediments at levels ranging from 102 to 105 cells/g sediment respectively. No difference between microbial communities present in vegetated versus non-vegetated sediments was found using terminal restriction fragment length polymorphism (of the 16S rRNA gene) or phospholipid fatty acid analysis. These studies provide information on the specific members and activity of the PAH-degrading aerobic bacterial communities present in Spartina-dominated salt marshes in the New York/New Jersey Harbor estuary.  相似文献   

12.
Arithmetic and lognormal means historically have been used as estimates of exposure concentration for both human health and ecological risk assessment. Past risk assessment guidance has emphasized the need to include all available informa tion, particularly regarding the spatial and temporal aspects of data and exposure. One estimate of exposure concentration that includes spatial information is the 95% upper confidence limit (UCL) of the area weighted mean. An area weighted mean is calculated using weightings based on the ratio of the area associated with a sample location and the total area of the study area. Currently, U.S. Environmental Protection Agency (USEPA) risk assessment guidance recommends the use of the 95% UCL of the arithmetic mean as the most appropriate measure of exposure concentration for soil and sediment in human health and ecological risk assess ments. The purpose of this study was two fold: (1) to evaluate the use of the 95% UCL of the area weighted mean vs. the 95% UCL of the arithmetic mean for the lognormal distribution and the normal distribution using a large data set from a recent riverine sediment characterization study, and (2) to evaluate the potential associated with the different approaches for reduction in surface sediment exposure concentrations for 2,3,7,8 TCDD and coplanar polychlorinated biphenyls (PCBs) for several subsets of the data. The results of this evaluation indicated that there was no significant reduction in exposure concentrations of the study area surface sediments after any of the selected higher concentration data points had been removed from the various data subsets. In addition, this evaluation indicated that, due to its dependence on the variance of the data, the 95% UCL of the arithmetic mean for a lognormal distribution produced subset exposure concentrations that were higher than the calculated concentrations of the full data set and produced the smallest percent changes in concentration compared to the other two measures. Based on this analysis, the 95% UCL of the area weighted mean was determined to be the most stable and appropriate estimator of exposure concentration for surface sediments.  相似文献   

13.
This study examines and quantifies the linkages between population health, environmental risks, and its determinants for drinking water in New Zealand using routinely collected data. It was conducted as part of the national environmental health indicators project in New Zealand. The project is based on the World Health Organization’s (WHO) “Environmental and Health Information System” program. Drinking water quality indicators based on the Driving force–Pressure–State–Exposure–Effect–Action (DPSEEA) framework as part of this program were analyzed to validate the model by quantifying the linkages between the indicators. The results of the model suggested over the study period, the state (drinking water quality) and exposure (water access) indicators are significant independent predictors of the effect indicator (waterborne disease rate). This study suggests that routinely collected data can be structured using the DPSEEA framework and tested quantitatively using standard Poisson regression models, thus, illustrating that the model can be used routinely to provide a basis for consideration of the costs and benefits of any interventions to reduce the burden of waterborne disease. Data quality issues need to be considered if such routinely collected data linkages are to be performed for policy purposes. The online version of this article (doi:) contains electronic supplementary material, which is available to authorized users. Supplemental histograms are available in the online appendix.  相似文献   

14.
15.
A methodology using existing, accessible public information is presented for the estimation of amounts of mercury that may have been applied to soils historically on agricultural land in the U.S. Estimations based on national agricultural consumption data reported by the Bureau of Mines can be apportioned further to the state and county level. For comparison, estimates using crop recommendations are presented, which can be considered to provide an upper-bound estimate of amounts potentially used on individual farms. In New Jersey, approximately 318,000?lb of mercury as an active ingredient could have been applied on approximately 150,000 acres of cropland and golf courses in the period 1921 to 1990. Based on crop recommendations, as much as 600,000 to over 1,000,000?lb of mercury could have been applied.  相似文献   

16.
The goal of this article is to present the Human Health Risk Assessment (HRA) software developed as one of the NORISC 1 1NORISC is the acronym of the project “Network Oriented Risk assessment by In-situ Screening of Contaminated sites” realized under under the 5th European Union Community Framework Programme for Research, Technological Development and Demonstration Activities. View all notes decision support software system components that could be used as a tool for facilitating management of urban contaminated sites. The NORISC-HRA software provides sufficient technical and procedural support to conduct a simple site-specific risk assessment. The employed HRA methodology is generally based on U.S. Environmental Protection Agency (USEPA) procedures. The software determines the level and spatial distribution of human health risks at a given site and sets up site-specific preliminary Health-Based Remedial Goals (HBRGs)/Risk-Based Concentrations (RBCs) for soil and groundwater. The NORISC-HRA software is recommended for use when national soil and groundwater limit values are exceeded. Exposure pathways considered in this software are associated with three land use patterns—residential, industrial/commercial, and recreational. The aricle also presents the software testing results obtained at one of the NORISC test sites—the Massa site (Avenza-Carrara, Tuscany, Italy). Findings of the HRA indicated that the contaminated soil at the Massa test site might pose potential cancer and non-cancer risks to industrial workers in its present condition. Arsenic was the dominant substance responsible for most of the baseline risk and at the RBC of 1.77 mg/kg it was the primary driver of remedial decisions at the Massa site.  相似文献   

17.
Sly  P. G. 《Hydrobiologia》1989,176(1):99-110
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18.
The chemical composition of rehabilitated Bauxite Residue Disposal Areas (BRDA) remains the primary indicator of rehabilitation success, with little consideration of microbial community development. We investigated links between the chemical and microbial components of rehabilitated residue at the Aughinish Alumina BRDA (Ireland). Rehabilitated was compared to unamended residue and to an analogy reference soil from unmanaged grassland within the refinery boundary. Bauxite residue comprised of areas with 1, 11, and 12 years following rehabilitation establishment, and gypsum applied at 45 and 90 t/ha. The unamended residue was typical of bauxite residues with high pH (10), sodicity (exchangeable sodium percentage [ESP]‐79), exchangeable sodium (19 cmol/kg), salinity (electrical conductivity [EC] 2.6 mS/cm), and low/negligible nutrient content, microbial biomass (71 µg‐C/g), and fungal phospholipid fatty acid (PLF). Microbial biomass increased 10‐fold with only 1 year of rehabilitation. Gypsum application rate had no effect on microbial biomass. Phospholipid fatty acid analysis (PLFA) demonstrated the emergence of distinct microbial community dependent on rehabilitation time and gypsum application rates. Changes of PLFA profiles were correlated (multiple regressions analysis) to shifts in residue chemical properties (sodicity, organic C, total C, total N, salinity, Mg). An increase of the arbuscular mycorrhizal fungi fatty acid (16:1ω5) with reducing pH has implications on rehabilitation practices. The microbial characteristics of the rehabilitated residue were approaching that of a soil from an unmanaged reference site adjacent to the working site. Gypsum affected PLFA properties, and thereby application has implications for rehabilitation success. For successful ecosystem reconstruction, it is critical that rehabilitation practices consider microbial development.  相似文献   

19.
A screening level human health risk assessment (HHRA) was applied to evaluate the human health implications of consuming selenium found in fish tissues collected downstream of coal mines in southeastern British Columbia, Canada. The study evaluated the potential for adverse human health effects associated with selenium, and considered known and potential benefits of selenium and fish ingestion. The results indicated that risks of selenosis due to consumption of selenium-contaminated fish in the region are negligible. Conclusions were strengthened by consideration of the potential benefits of selenium to human health, including: selenium essentiality for maintenance of good health; potential cancer prevention properties due to its role as an antioxidant; potential benefits for cardiovascular health; and other positive health benefits. The findings indicated that some aspects of the traditional framework for HHRA (e.g., application of safety factors to “err on the side of safety”) are inappropriate for the assessment of selenium-contaminated fish. Due to both deficiency and toxicity in the selenium dose-response relationship, application of compounding conservatism in risk assessment may lead to recommended intakes of fish that are contrary to the public health interest. The need for balancing risk types, for incorporating positive responses in risk assessments, and the linkage to the precautionary principle, are discussed.  相似文献   

20.
Product lifetime is an essential aspect of dynamic material flow analyses and has been modeled using lifetime distribution functions, mostly average lifetimes. Existing data regarding the lifetime of electronic equipment (EE) are based on diverging definitions of lifetime as well as different temporal and regional scopes. After its active use, EE is often not disposed of immediately, but remains in storage for some time. Specific data on the share of EE that is stored and the time they remain in storage are scarce. This article investigates the service lifetime, storage time, and disposal pathways of ten electronic device types, based on data from an online survey complemented by structured interviews. We distinguish between new and secondhand devices and compute histograms, averages, and medians of the different lifetimes and their change over time. The average service lifetime varies from 3.3 years for mobile phones to 10.8 years for large loudspeakers, the average storage time from 0.8 years for flat panel display televisions to 3.6 years for large loudspeakers. Most service lifetime histograms are positively skewed and show substantial differences among device types. The storage time histograms, being more similar to one another, indicate that the storage behavior is similar for most device types. The data on disposal pathways show that a large proportion of devices are stored and reused before they reach the collection scheme.  相似文献   

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