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1.
Unsightly and environmentally damaging debris is an ever present problem for waterways and beaches around the world. This debris has numerous sources, and is comprised of materials ranging from metal and wood to plastics and paper. the aesthetic, economic, and environmental impacts of debris have been well documented over the past several years. in an effort to control the release of trash and debris into our waters, there are many activities ongoing in the US. One such activity is a coordinated effort between the US Environmental Protection Agency (EPA), other federal Agencies (National Oceanic and Atmospheric Administration (NOAA), United States Coast Guard (USCG), United States Navy (USN), National Park Service (NPS), Department of Interior (DOI)), industry (the Society of the Plastics Industry, INC. (SPI)), environmental, and local groups. This paper describes the results of field assessments, and the other activities undertaken by EPA as part of this coordinated effort to control the release of debris to our nation's waterways.  相似文献   

2.
As part of a programme to characterize floating anthropogenic debris in the aquatic environment, the US Environmental Protection Agency (EPA) conducted 18 field surveys in the harbours of major metropolitan cities of the east, west, and Gulf coasts of the United States and the Mid-Atlantic Bight. the surveys were designed to provide information on the types, relative amounts, and distributions of aquatic debris in different geographic regions of the United States. Neuston nets (0.33 mm mesh) were used to collect surface debris during outgoing tides on two or three consecutive days in selected areas of each city. After each net tow, the debris, which ranged in size from small resin pellets to large plastic sheeting pieces, was identified, categorized, and counted. the data are being used to qualitatively characterize aquatic debris in coastal metropolitan areas, to examine potential regional variations, and to tentatively identify potential sources.  相似文献   

3.
As part of a programme to characterize floating anthropogenic debris in the aquatic environment, the US Environmental Protection Agency (EPA) conducted 18 field surveys in the harbours of major metropolitan cities of the east, west, and Gulf coasts of the United States and the Mid-Atlantic Bight. the surveys were designed to provide information on the types, relative amounts, and distributions of aquatic debris in different geographic regions of the United States. Neuston nets (0.33 mm mesh) were used to collect surface debris during outgoing tides on two or three consecutive days in selected areas of each city. After each net tow, the debris, which ranged in size from small resin pellets to large plastic sheeting pieces, was identified, categorized, and counted. the data are being used to qualitatively characterize aquatic debris in coastal metropolitan areas, to examine potential regional variations, and to tentatively identify potential sources.  相似文献   

4.
Abstract

Small-scale miners often engage in environmentally damaging activities, are subject to poor safety conditions, and utilize inefficient mineral extraction technologies. Here, we explore environmental impacts to surface waters from regional artisanal small-scale gold placer mining operations conducted in iron and aluminum-rich saprolites found within the lateritic, interior Amazon rainforest of Suriname. Heavy equipment was utilized to release gold from its host material followed by amalgamation and gravity separation. In contrast with background tributary recordings, streams adjacent to these gold mining operations consistently contained turbidity measurements that exceeded United States’ EPA guidelines for aquatic species of 50 nephelometric turbidity units and were typically in the hundreds to thousands of units. Turbidity was further heightened in association with precipitation events. Mercury played a prominent role in whole ore amalgam concentration practices. Freshwater fish from the region were found to harbor mercury that encroached upon public health criteria. Dissolved phase metals present further ecotoxicological challenges to the region, but their association with mining activities was less clear. These findings collectively reveal that small-scale placer gold mining practices in the Surinamese rainforest result in an increase of suspended sediments and release of mercury into waterways that could impact communities that depend upon local fisheries.  相似文献   

5.
For major federal environmental statutes in the United States, primary monitoring and enforcement responsibilities rest with most states. The Environmental Protection Agency (EPA) is charged with overseeing state efforts and has at its disposal formal tools to discipline lax states, tools which are rarely used. In this paper, we explore the extent to which the EPA's now-defunct Clean Air Act Watch List served as an informal tool for influencing the enforcement activities of state regulators. We estimate event studies designed around the primary listing criteria for the Watch List. Our empirical results are consistent with the average state regulator acting to reduce the chances of their facilities appearing on the Watch List. We also examine heterogeneity in the response to the Watch List between two states with high numbers of regulated facilities, Texas and California. We find a larger change in enforcement activity under the Watch List among state and local regulators in Texas compared to California.  相似文献   

6.
《Ecological modelling》2004,171(3):271-278
The development of genetically modified Bt-corn, incorporating various toxin genes from Bacillus thuringiensis that act as a chemical defense against insect pests, such as the European Corn Borer, provides farmers with a new pest management option. However, the emergence of insect resistance is a threat to the continued use of Bt-corn. The United States Environment Protection Agency (US EPA) has developed planting strategies, for preventing insect resistance by planting a mixture of Bt- and non-Bt-corn. Decisions about the exact proportion of Bt- and non-Bt-corn are based on complex spatially explicit mathematical models using detailed biological assumptions about the population genetics and life history of the European Corn Borer. We develop an alternative simpler model for the spread of resistance based on the logistic growth model, which we believe has utility in situations where it is impossible or impractical to estimate the different life history and genetics parameters required by more detailed models. We use our model to investigate the US EPA’s planting rules for Bt-corn and find that short-term economic behavior is likely to lead to these rules not being followed. Our results add weight to existing work on this problem. We also investigate the economics of planting Bt-corn in markets where consumers do and do not differentiate between the modes of production for the corn. We find that Bt-corn appears to be economic in markets that do not differentiate and uneconomic in markets where consumers do differentiate.  相似文献   

7.
The purpose of this blinded study was to evaluate potential environmental toxicity in a cohort of neurotypical children (n = 28) living in a suburban area of north-central Texas in the United States (US) with a comparable age- and gender-matched cohort of neurotypical children (n = 28) living in a suburban area of southeastern France using urinary porphyrin testing: uroporphyrin (uP), heptacarboxyporphyrin (7cxP), hexacarboxyporphyrin (6cxP), pentacarboxyporphyrin (5cxP), precoproporphyrin (prcP), and coproporphyrin (cP). Results showed significantly elevated 6cxP, prcP (an atypical, mercury-specific porphyrin), and cP levels, and increasing trends in 5cxP levels, among neurotypical children in the USA compared to children in France. Data suggest that in US neurotypical children, there is a significantly increased body-burden of mercury (Hg) compared to the body-burden of Hg in the matched neurotypical children in France. The presence of lead contributing to the higher levels of cP also needs to be considered. Further, other factors including genetics can not be completely ruled out.  相似文献   

8.
This article assesses the air pollution data from two monitoring stations in Kuwait. The measurements cover major pollutants, i.e., CO, CO2, methanated and non-methanated hydrocarbons, NO x , SO2, O3, and particulate matter (PM10). The data also includes meteorological parameters, i.e., solar intensity, temperature, wind speed, and wind direction, and has been collected over a period 4 years, from 2001 to 2004. Data analysis includes the assessment of annual hourly averages and 1-h maxima. Typical pollutant concentration trends, similar to those previously reported for Kuwait and for other locations around the world, are observed except for particulate matter measurements, which have higher values because of proximity to the desert. Emissions of nitrogen oxides show a consistent increase over the years. This is caused by the increase in the number of motor vehicles and the expansion in power generation and industrial activities. The data collected is a subset of the air quality criteria, as defined by the US EPA (United States Environmental Protection Agency).  相似文献   

9.
Forecasting the Expansion of Zebra Mussels in the United States   总被引:4,自引:1,他引:3  
Abstract:  Because zebra mussels spread rapidly throughout the eastern United States in the late 1980s and early 1990s, their spread to the western United States has been expected. Overland dispersal into inland lakes and reservoirs, however, has occurred at a much slower rate than earlier spread via connected, navigable waterways. We forecasted the potential western spread of zebra mussels by predicting the overland movement of recreational boaters with a production-constrained gravity model. We also predicted the potential abundance of zebra mussels in two western reservoirs by comparing their water chemistry characteristics with those of water bodies with known abundances of zebra mussels. Most boats coming from waters infested with zebra mussels were taken to areas that already had zebra mussels, but a small proportion of such boats did travel west of the 100th meridian. If zebra mussels do establish in western U.S. water bodies, we predict that population densities could achieve similar levels to those in the Midwestern United States, where zebra mussels have caused considerable economic and ecological impacts. Our analyses suggest that the dispersal of zebra mussels to the western United States is an event of low probability but potentially high impact on native biodiversity and human infrastructure. Combining these results with economic analyses could help determine appropriate investment levels in prevention and control strategies .  相似文献   

10.
Erionite, a mineral series within the zeolite group, is classified as a Group 1 known respiratory carcinogen. This designation resulted from extremely high incidences of mesothelioma discovered in three small villages from the Cappadocia region of Turkey, where the disease was linked to environmental exposures to fibrous forms of erionite. Natural deposits of erionite, including fibrous forms, have been identified in the past in the western United States. Until recently, these occurrences have generally been overlooked as a potential hazard. In the last several years, concerns have emerged regarding the potential for environmental and occupational exposures to erionite in the United States, such as erionite-bearing gravels in western North Dakota mined and used to surface unpaved roads. As a result, there has been much interest in identifying locations and geologic environments across the United States where erionite occurs naturally. A 1996 U.S. Geological Survey report describing erionite occurrences in the United States has been widely cited as a compilation of all US erionite deposits; however, this compilation only focused on one of several geologic environments in which erionite can form. Also, new occurrences of erionite have been identified in recent years. Using a detailed literature survey, this paper updates and expands the erionite occurrences database, provided in a supplemental file (US_erionite.xls). Epidemiology, public health, and natural hazard studies can incorporate this information on known erionite occurrences and their characteristics. By recognizing that only specific geologic settings and formations are hosts to erionite, this knowledge can be used in developing management plans designed to protect the public.  相似文献   

11.
Aluminum is a ubiquitous substance with over 4,000 uses. Aluminum, as aluminum sulfate, is commonly used in the United States as a coagulant in the treatment of drinking water. For many years aluminum was not considered to be toxic to humans. However, reports associating aluminum with several skeletal and neurological disorders in humans suggest that exposure to aluminum may pose a health hazard. In 1983 the US Environmental Protection Agency (EPA) announced plans to regulate a number of substances, including aluminum, in drinking water. Aluminum was considered because of its occurrence and apparent toxicity. Upon further evaluation of the health effects data the EPA proposed not to regulate aluminum as a result of the uncertainty of the toxicity of ingested aluminum. Putative causal associations between aluminum exposure and neurological disorders such as Alzheimer's disease have yet to be substantiated. Although several issues regarding the toxicity of ingested aluminum are unresolved, aluminum has been specified in the 1986 Amendments to the Safe Drinking Water Act, as one of 83 substances in drinking water to be regulated by 1989. Additional data are needed before the potential risk of aluminum can be assessed; therefore the EPA has deferred possible regulation until 1991.  相似文献   

12.
Finding ways to increase financial support is critical to conservation efforts. We used conservation fundraising data, unprecedented in their resolution, to reveal spatial patterns in philanthropic giving to a major land protection organization in the United States. We also quantified the relationship between the amount of effort devoted to fundraising and donations received. Around 40% of the variation in the propensity to give and overall value of gifts was explained by sociodemographic and other predictors. For example, education level had greater predictive capacity than income, political views, and other factors often considered important. Fundraising effort was strongly predictive of the amount donated in an area. Our model estimated a doubling of funds raised with a 5-fold increase of effort. Conservation organizations could use our statistical framework to inform efforts aimed at increasing philanthropic giving by identifying locations with large model residuals. An example application of our framework showed an almost 40% increase (US$200 million) in fundraising revenue for the case-study conservation organization.  相似文献   

13.
We develop regional-scale eutrophication models for lakes, ponds, and reservoirs to investigate the link between nutrients and chlorophyll-a. The Bayesian TREED (BTREED) model approach allows association of multiple environmental stressors with biological responses, and quantification of uncertainty sources in the empirical water quality model. Nutrient data for lakes, ponds, and reservoirs across the United States were obtained from the Environmental Protection Agency (EPA) National Nutrient Criteria Database. The nutrient data consist of measurements for both stressor variables (such as total nitrogen and total phosphorus), and response variables (such as chlorophyll-a), used in the BTREED model. Markov chain Monte Carlo (McMC) posterior exploration guides a stochastic search through a rich suite of candidate trees toward models that better fit the data. The Bayes factor provides a goodness of fit criterion for comparison of resultant models. We randomly split the data into training and test sets; the training data were used in model estimation, and the test data were used to evaluate out-of-sample predictive performance of the model. An average relative efficiency of 1.02 between the training and test data for the four highest log-likelihood models suggests good out-of-sample predictive performance. Reduced model uncertainty relative to over-parameterized alternative models makes the BTREED models useful for nutrient criteria development, providing the link between nutrient stressors and meaningful eutrophication response.  相似文献   

14.
The landscape of the conterminous United States has changed dramatically over the last 200 years, with agricultural land use, urban expansion, forestry, and other anthropogenic activities altering land cover across vast swaths of the country. While land use and land cover (LULC) models have been developed to model potential future LULC change, few efforts have focused on recreating historical landscapes. Researchers at the US Geological Survey have used a wide range of historical data sources and a spatially explicit modeling framework to model spatially explicit historical LULC change in the conterminous United States from 1992 back to 1938. Annual LULC maps were produced at 250-m resolution, with 14 LULC classes. Assessment of model results showed good agreement with trends and spatial patterns in historical data sources such as the Census of Agriculture and historical housing density data, although comparison with historical data is complicated by definitional and methodological differences. The completion of this dataset allows researchers to assess historical LULC impacts on a range of ecological processes.  相似文献   

15.
The U.S. EPA has initiated the 33/50 program to encourage firms to voluntarily reduce releases and transfers of 17 toxic chemicals. This paper evaluates the factors leading to participation in this program to assess its potential to augment more traditional command and control regulation. The results show that large firms with substantial toxic releases in unconcentrated industries are the most likely participants. The results also indicate that public information and awareness plays an important role and that EPA and other regulators can improve environmental performance by encouraging competition in environmental quality.  相似文献   

16.
This paper presents a unique data set of lead, arsenic, polychlorinated biphenyl (PCB), and polycyclic aromatic hydrocarbon (PAH) concentrations in soil samples collected from the metropolitan New York City area in the aftermath of Hurricane Sandy. Initial samples were collected by citizen scientists recruited via social media, a relatively unusual approach for a sample collection project. Participants in the affected areas collected 63 usable samples from basements, gardens, roads, and beaches. Results indicate high levels of arsenic, lead, PCBs, and PAHs in an area approximately 800 feet south of the United States Environmental Protection Agency (US EPA) Superfund site at Newtown Creek. A location adjacent to the Gowanus Canal, another Superfund site, was found to have high PCB concentrations. Areas of high PAH contamination tended to be near high traffic areas or next to sites of known contamination. While contamination as a direct result of Hurricane Sandy cannot be demonstrated conclusively, the presence of high levels of contamination close to known contamination sites, evidence for co-contamination, and decrease in number of samples containing measureable amounts of semi-volatile compounds from samples collected at similar locations 9 months after the storm suggest that contaminated particles may have migrated to residential areas as a result of flooding.  相似文献   

17.
This article proposes an analytical framework for developing indicators of agriculture and rural community sustainability, including the symbiotic relationship between sustainable agriculture and rural well-being. Rural well-being offers a sustainable approach to healthy lifestyles that are based on a balance of many complex components including social, economic, and environmental issues. The United States (US) and the United Kingdom (UK) have taken positions on these issues. The United States Department of Agriculture is ‘committed to helping improve the economy and quality of life in rural America’ through loans and subsidies (USDA 2015). The USDA Sustainable Agriculture Research and Education (SARE) program vision is to sustain ‘an enduring American agriculture of the highest quality that is profitable, protects the nation’s land and water and is a force, providing a healthy and rewarding way of life for farmers and ranchers whose quality products and operations sustain their communities and society’ (SARE 2016; Smart, Sandt and Chris Zdorovtsov 2016). UK government and non-government agencies have taken a more holistic approach to rural well-being in their efforts to achieve a more balanced social–economic–environmental state of rural well-being. The UK interpretation of Community Supported Agriculture is a tested example of this sustainable approach to fostering rural well-being (Saltmarsh et al. 2011).  相似文献   

18.
美国露天采矿环境保护标准及其对我国的借鉴意义   总被引:1,自引:1,他引:1  
概述了美国露天采矿环境保护标准并总结其特点:(1)一般性和特殊性相结合;(2)采矿破坏地生态恢复涵义广,涉及矿区内所有受扰地区;(3)管理当局可针对具体矿山更改某些要求;(4)有完善的配套法规保障标准的执行。基于美国在采矿环境保护方面的经验,提出了我国矿产开发生态保护与恢复标准制定的4点设想:(1)涵盖矿产开发造成生态影响的每一个环节和所有的受扰地区;(2)尽量考虑各种具体情况;(3)体现生态恢复的全面性;(4)完善相关法规,保障标准实施。  相似文献   

19.
自1938年美国首先颁布管控化学品的法律以来,健康风险评估逐步发展,各个国家和地区相继颁布文件,并已形成较为完善的评估框架.由于在化学品健康风险评估的过程中,存在大量收集引用的数据及信息,因此数据质量评估是保证风险评估结果可信的关键.目前为止美国环保署(environmental protection agency,EPA)和欧盟《化学品的注册、评估、授权和限制》(regulation concerning the registration,evaluation,authorization and restriction of chemicals,REACH)法规均对数据质量评估方法进行了详细的规定.两个地区均采用数据评分(1—4)与证据权重(weight of evidence,WOE)(1/2)相结合的评估方法,不同之处在于欧盟更侧重于对数据整体的相关性、可靠性和充分性进行评估和打分,U.S EPA则更为细致具体,其侧重于不同情境下的数据分组分析,根据不同的评分领域和指标,规定高置信度、中置信度、低置信度和数据不可接受的标准.通过总结对比欧盟及美国的数据质量评估方法,建议我国采用数据打分与证据权重相结合的定量评估方法,并明确规定不同情景下不同数据来源的打分规则和标准,使数据质量评估过程系统化.  相似文献   

20.
The debate about Superfund liability has treated financing as a distinct issue from the efficiency of clean-up. However, this paper presents a model of EPA decision-making in which liability funding may increase or decrease the extent of clean-up. It then estimates this effect using data on remedies selected at National Priorities List sites and on the characteristics of liable parties. The results suggest that the EPA responds to concentrated private interests, selecting less extensive clean-up when liable parties are expected to bear a large share of costs. This effect should be considered in evaluating liability approaches to environmental protection.  相似文献   

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