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We have demonstrated a novel sensing strategy employing a giant magnetoresistance (GMR) biosensor and DNA chemistry for the detection of mercuric ion (Hg2+). This assay takes advantages of high sensitivity and real-time signal readout of GMR biosensor and high selectivity of thymine-thymine (T-T) pair for Hg2+. The assay has a detection limit of 10 nM in both buffer and natural water, which is the maximum mercury level in drinking water regulated by U.S. Environmental Protection Agency (EPA). The magnitude of the dynamic range for Hg2+ detection is up to three orders (10 nM to 10 μM). Herein, GMR sensing technology is first introduced into a pollutant monitoring area. It can be foreseen that the GMR biosensor could become a robust contender in the areas of environmental monitoring and food safety testing. [ABSTRACT FROM AUTHOR]

In this article the authors discuss the U.S. Environmental Protection Agency (EPA). The focus of the article is the need for an integrated systems approach for effective environmental protection in the 21st century. Topics include an overview of the evolution of U.S. environmental science and policy, the creation of the National Environmental Policy Act (NEPA) and Ash Council, and sustainability science and technology in the 21st century.

The article focuses on China's efforts to reduce pollution. It comments on the environmentally-friendly architecture used to host the 2008 Olympic Games in Beijing, including such endeavors as recycled water and biodegradable plastics. It mentions that China burns enough coal for electricity and energy and accounts to almost five percent of worldwide greenhouse gas emissions. It comments on the State Environmental Protection Administration of China and the Ministry of Environmental Protection's (MEP) efforts to enforce environmental standards, and of resistance to mandates by local governments in China to keep up environmental growth. It mentions that there is a partnership between the United States Environmental Protection Agency and the MEP to help China improve energy efficiency.

A new efficient and highly selective fluorescent chemosensor for determination of Pb2+ has been obtained by covalent attachment of two pendent proton-ionizable dansylcarboxamide groups to the calix[4]arene preorganized in the partial cone conformation. This geometry of the calixarene moiety was chosen on the basis of the prior ¹H NMR study of conformations adopted by the flexible dansyl-containing prototype upon complexation with lead ion. In acidic MeCN-H20 (1:1 v/v) solutions, the partial cone fluoroionophore allowed for detection of Pb2+ at the levels as low as 2.5 ppb, which is totally compatible with the regulations of the U.S. Environmental Protection Agency and the World Health Organization on the limiting content of this hazardous pollutant in drinking water. [ABSTRACT FROM AUTHOR]

In this paper, we present findings from a multiyear expert judgment study that comprehensively characterizes uncertainty in estimates of mortality reductions associated with decreases in fine particulate matter (PM2.5) in the U.S. Appropriate characterization of uncertainty is critical because mortality- related benefits represent up to 90% of the monetized benefits reported in the Environmental Protection Agency's (EPA's) analyses of proposed air regulations. Numerous epidemiological and toxicological studies have evaluated the PM2.5—mortality association and investigated issues that may contribute to uncertainty in the concentration—response (C—R) function, such as exposure misclassification and potential confounding from other pollutant exposures. EPA's current uncertainty analysis methods rely largely on standard errors in published studies. However, no one study can capture the full suite of issues that arise in quantifying the C—R relationship. Therefore, EPA has applied state-of-the-art expert judgment elicitation techniques to develop probabilistic uncertainty distributions that reflect the broader array of uncertainties in the C—R relationship. These distributions, elicited from 12 of the world's leading experts on this issue, suggest both potentially larger central estimates of mortality reductions for decreases in long-term PM2.5 exposure in the U.S. and a wider distribution of uncertainty than currently employed in EPA analyses. [ABSTRACT FROM AUTHOR]

The Clean Air Act establishes New Source Review (NSR) programs that apply to construction or modification of major stationary sources. In 2002 and 2003, EPA revised its rules to narrow NSR's coverage of renovations. Congress mandated a National Research Council study of the revisions' impacts. In that study, we used an electricity-sector model to explore possible effects of the equipment replacement provision (ERP), the principal NSR change directed at power plants. We find that, assuming implementation of the Clean Air Interstate Rule (CAIR), tight enforcement of the prerevision NSR rules would likely lead to no or limited decreases in national emissions compared to policies such as ERP. However, emissions might shift forward in time because the previous NSR rules would depress allowance prices, discouraging banking and encouraging allowance use. Only under the most aggressive prerevision NSR enforcement scenario, in which essentially all coal capacity is compelled to retrofit controls by 2020, do NOx emissions fall below ERP levels. Even then, total 2007-2020 SO2 emissions are unaffected. Further decreases in national emissions could be accomplished more cheaply by tighter emissions caps than through NSR because caps provide incentives for efficient operating strategies, such as fuel switching, as well as retrofits. [ABSTRACT FROM AUTHOR]

Groundwater within Area 3 of the U.S. Department of Energy (DOE) Environmental Remediation Sciences Program (ERSP) Field Research Center at Oak Ridge, TN (ORFRC) contains up to 135 μM uranium as U(VI). Through a series of experiments at a pilot scale test facility, we explored the lower limits of groundwater U(VI) that can be achieved by in-situ biostimulation and the effects of dissolved oxygen on immobilized uranium. Weekly 2 day additions of ethanol over a 2-year period stimulated growth of denitrifying, Fe(III)-reducing, and sulfate-reducing bacteria, and immobilization of uranium as U(IV), with dissolved uranium concentrations decreasing to low levels. Following sulfite addition to remove dissolved oxygen, aqueous U(VI) concentrations fell below the U.S. Environmental Protection Agengy maximum contaminant limit(MCL) for drinking water ( <30 μg L-1 or 0.126 μM). Under anaerobic conditions, these low concentrations were stable, even in the absence of added ethanol. However, when sulfite additions stopped, and dissolved oxygen (4.0- 5.5 mg L-1) entered the injection well, spatially variable changes in aqueous U(VI) occurred over a 60 day period, with concentrations increasing rapidly from <0.13 to 2.0 μM at a multilevel sampling (MLS) well located close to the injection well, but changing little at an MLS well located further away. Resumption of ethanol addition restored reduction of Fe(III), sulfate, and U(VI) within 36 h. After 2 years of ethanol addition, X-ray absorption near-edge structure spectroscopy (XANES) analyses indicated that U(IV) comprised 60-80% of the total uranium in sediment samples. At the completion of the project(day 1260), U concentrations in MLS wells were less than 0.1 μM. The microbial community at MLS wells with low U(VI) contained bacteria that are known to reduce uranium, including Desulfovibrio spp. and Geobacter spp., in both sediment and groundwater. The dominant Fe(III)-reducing species were Geothrix spp. [ABSTRACT FROM AUTHOR]

The U.S. Department of Housing and Urban Development, in collaboration with the U.S. Consumer Product Safety Commission and the U.S. Environmental Protection Agency, characterized the environments of young children (<6 years) by measuring lead, allergens, and pesticides in a randomly selected nationally representative sample of licensed institutional child care centers. Multi-stage sampling with clustering was used to select 168 child care centers in 30 primary sampling units in the United States. Centers were recruited into the study by telephone interviewers. Samples for pesticides, lead, and allergens were collected at multiple locations in each center by field technicians. Field sampling was conducted from July through October 2001. Wipe samples from indoor surfaces (floors, tabletops, desks) and soil samples were collected at the centers and analyzed using a multi-residue GC/MS analysis method. Based on the questionnaire responses, pyrethroids were the most commonly used pesticides among centers applying pesticides. Among the 63% of centers reporting pesticide applications, the number of pesticides used in each center ranged from 1 to 10 and the frequency of use ranged from 1 to 107 times annually. Numerous organophosphate and pyrethroid pesticides were detected in the indoor floor wipe samples. Chlorpyrifos (0.004–28 ng/cm²), diazinon (0.002–18 ng/cm²), cis-permethrin (0.004–3 ng/cm²), and trans-permethrin (0.004–7 ng/cm²) were detected in >67% of the centers. Associations exist between residues measured on the floor and other surfaces for several pesticides (p-values range from <0.0001 to 0.002), but to a lesser degree between floor and soil and other surfaces and soil. Regional analyses indicate no differences in mean level of pesticide loading between the four Census regions (0.08 < p < 0.88). Results show that there is the potential for exposure to pesticides in child care centers. [ABSTRACT FROM AUTHOR]

We present a Bayesian approach for characterizing background contaminant concentration distributions using data from sites that may have been contaminated. Our method, focused on estimation, resolves several technical problems of the existing methods sanctioned by the U.S. Environmental Protection Agency (USEPA) (a hypothesis testing based method), resulting in a simple and quick procedure for estimating background contaminant concentrations. The proposed Bayesian method is applied to two data sets from a federal facility regulated under the Resource Conservation and Restoration Act. The results are compared to background distributions identified using existing methods recommended by the USEPA. The two data sets represent low and moderate levels of censorship in the data. Although an unbiased estimator is elusive, we show that the proposed Bayesian estimation method will have a smaller bias than the EPA recommended method. [ABSTRACT FROM AUTHOR]

It has been almost 40 years since scientists and regulators began to publicly recognize that volatile organic compounds (VOCs) differ in their potential to form ozone. Since 1977, our understanding of the mechanisms by which VOCs contribute to ozone formation has grown substantially. An assessment o1 the science indicates that we now have sufficient understanding to develop and implement a more efficient approach to VOC control policy that will promote smarter, more cost-effective V0C controls. Furthermore, the U.S. Environmental Protection Agency's recently published Interim Guidance on Control of Volatile Organic Compounds in Ozone State Implementation Plans ‘encourages States to consider recent scientific information on the photochemical reactivity of volatile organic compounds (VOC) in the development of State implementation plans (SIPs).’ As has been demonstrated by the California Air Resources Board's Aerosol Coatings Rule and the recent experience in Houston addressing high-reactivity VOCs, reactivity-based regulations may be more effective and efficient than mass-based rules in many applications. It is time for regulators, industry, and other stakeholders to work together to accelerate efforts to bring about a new paradigm in V0C control, in which the focus is on the ozone-forming potential of V0C emissions, rather than the mass of VOCs emitted. [ABSTRACT FROM AUTHOR]

The article provides an overview of the mercury control technologies aimed at lessening the mercury emissions from coal-fired electric utility boilers in the U.S. The author stressed that mercury emissions from anthropogenic emission sources posed a global threat that needs to be subsided. In response, the U.S. Environmental Protection Agency proclaimed the Clean Air Mercury Rule to permanently cap and abridge emissions of mercury from coal-fired power plants. Another regulation promulgated is the Clean Air Interstate Rule, which compels further reduction of sulphur dioxide and nitrogen oxides from these power plants. Among the control technologies stressed include flue-gas desulfurization and limestone forced- oxidation.

Holding a series of listening sessions to gather input on a new research initiative into environmentally related health effects for older Americans seemed like a winning idea for the U.S. Environmental Protection Agency. But as each session unfolded, criticisms of EPA's cost-benefit analysis approach was on the front pages of local newspapers. At the final listening session in Baltimore, Maryland, on May 7, 2003 former EPA administrator Christie Whitman pulled the plug on what came to be known as the senior discount asserting that no agency policy decisions have ever been made on the basis of this analytical approach. The senior discount caught the public's attention to such an extent that the U.S. House of Representatives in late July 2003 added language to EPA's funding bill that would prohibit the agency from applying this discount.

Examines floating spatial domain averaging in surface soil remediation. Background on the United States Environmental Protection Agency's (EPA) soil screening process; Floating spatial domain averaging; Cleanup goal and site extents.

Cites the commitment of United States Environmental Protection Agency Administrator Carol Browner to facilitating practical approaches for effectively implementing environmental regulations. Evolving framework for environmental protection; Concerns about major environmental issues; Proposed Better America Bonds program; Comments on climate impact and prevention.

Presents an interview with Tom Donahue, president of the United States Chamber of Commerce, on national environmental issues. Inadequacy of proposals supported by environmental groups and the Environmental Protection Agency (EPA); Chamber opposition to the implementation of the Kyoto Protocol; Criticisms on the cost of government regulations; Opposition of the Chamber to the EPA environmental justice policy.

Offers an overview of the future role of the Environmental Protection Agency in environmental protection by 2010. Focus on the areas of environmental research environmental management; Development of an integrated approach to pollution control; Initiation of sectoral, place- and substance-based programs; Incorporation of environmental considerations into policies of nonenvironmental agencies.

Takes a critical look at the achievements and failures of the Environmental Protection Agency (EPA) in its 25 years of federal environmental protection. Environmental conditions before EPA; Regulation of air and water emissions; Pesticides and toxic chemical regulation; Administrative versus statutory reforms; Deregulation initiatives; Prospects for the EPA's future.

Focuses on issues which faced the Enivornmental Protection Agency (EPA). Details on the EPA water quality policies to speed implementation of the total maximum daily load (TDML) program; Why the federal court rejected the EPA's agrument on importing polychlorinated biphenyl (PCB). INSET: Confidential data controls may be tightened..

This article discusses environmental regulations promulgated by U.S. President George W. Bush during the last months of his term in 2008 and 2009. Political debates regarding the propriety of changes to environmental regulations such as the Clean Air Act and the regulation of mountaintop removal coal mining are assessed. The authors describe the increasing incidence of non-concurrence memos, where staff members at agencies such as the U.S. Environmental Protection Agency express their disagreement with proposed regulations. The efforts of the Bush administration to ensure that these regulations were in force by the time that U.S. President Barack Obama took office are explained.

The article discusses a plan by the United States Environmental Protection Association to repair dead zones that have formed in the Gulf of Mexico. Dead zones have formed in the Gulf over the past four decades because of farm fertilizers that run down the Mississippi River and feed algal blooms that choke oxygen supplies. The plan, which is scheduled to release in June 2008, is likely to fail unless it receives new funding from United States Congress, according to the author. A map of states that contribute pollutants to the Gulf is included.

The article reports on the budget cuts made to the $7.2 billion proposed funding for the U.S. Environmental Protection Agency (EPA). Researchers said that several EPA laboratories are struggling to cope with the cuts for they are having trouble conducting studies that support policy or regulations due to failure of obtaining supplies, equipment, laboratory animals, or skilled technicians. Support for research and development at EPA has declined by 25 percent in inflation-adjusted terms between the recent high point in 2004 and the proposed 2008 budget.

The article reports that representatives for U.S. Environmental Protection Agency (EPA) scientists are asking the Congress to stop the Bush administration from closing the agency's network of technical research libraries. Scientists believe that the action would lead their jobs harder because of a basic lack of information. The EPA scientists, representing more than half of the total agency workforce, contend thousands of scientific studies are being put out of reach, hindering emergency preparedness, anti-pollution enforcement and long-term research. EPA accelerated the closure of some of its 26 libraries last year in anticipation of a proposed budget for 2007.

The article reports on the performance of the environmental program called Performance Track established in 2000 by the U.S. Environmental Protection Agency (EPA). The Performance Track is composed of companies with exemplary environmental performance working voluntarily to improve habitat protection, water and energy use, and waste reduction in areas over which EPA has a regulatory authority. With its establishment in 2000, the program has been running off the rails and acted in favor of polluters. This is due to its call to abolish the report that may help improve pollution technologies along with changes that may permit companies to break environmental protection promises. The program has gone far beyond public recognition of the most responsible companies and raises several concerns.

The article reports that U.S. President George W. Bush has suggested a $7.3 billion budget for the Environmental Protection Agency (EPA) for fiscal year 2007. This represents a 4 percent reduction compared to its current funding. However, the president has requested Congress to provide $55 million more for EPA's homeland security initiatives and has shifted funding to expand research in nanotechnology and computational toxicology. However, funding for the agency's Office of Research and Development will be reduced slightly.

This article reports that as the result of testing the air emissions from more than 30,000 indoor office furnishings and products-including many office cubicles-over 30 years, Marilyn Black, a scientist, attests that most newer office furniture and equipment produce much fewer potentially toxic emissions than their predecessors. A typical cubicle has at least a dozen components, including coatings, varnishes, fiberglass, textiles, fabrics, adhesives, and finishes. By making the first measurements of the emissions coming from cubicles in the mid-1980s, it was revealed that some of those components were sources of toxic compounds. That was an incentive for action, especially given that some of Black first cubicle tests were conducted as part of a legal settlement. Employees had alleged that the cubicles inside U.S. Environmental Protection Agency buildings-including the water side Mall headquarters in emitting off of furniture, carpeting, and wall coverings were pretty much staying in the building and being recirculated.

This discusses chloramine complications. Alternatives to drinking-water chlorination, such as chloramines, may produce increased concentrations of disinfection by-products with toxicities far more potent than those currently regulated. The research was inspired by a 2002 drinking-water survey conducted by the U.S. Environmental Protection Agency, which revealed that iodide-containing compounds were forming in some drinking water at concentrations on the order of 10 micrograms per liter. The findings suggests that the switch in drinking-water disinfectants may cause increased adverse health effects in the U.S. population.

Reports that the U.S. Environmental Protection Agency is revising its approach for identifying emerging drinking water contaminants in response to recommendations from the U.S. National Research Council. Publication of a list of unregulated contaminants; Need to detect contaminants at low concentrations in water.

Reports that the United States Environmental Protection Agency is a step closer to developing a national regulation that prohibits discharging of toxic chemicals into U.S. waters at levels exceeding federal water quality criteria. Provisions of the said environmental regulation; Expected date of implementation.

Reports on developments involving the United States Environmental Protection Agency (EPA) and its policies as of June 2000. Controversies involving the scientific underpinnings of studies used to support the quest of EPA to regulate fine particles; Enforcement initiative that targets nitrogen oxide emissions from the petroleum and utility industries.

Focuses on developments related to environmental policies and the United States Environmental Protection Agency, current as of April 1, 2000. Includes studies on the environmental impact of the growing service sector; Criticisms against a proposed voluntary chemical testing program directed at children's safety.

Reports on developments concerning the United States Environmental Protection Agency (EPA) as of October 1999. Includes the Public Employees for Environmental Responsibility's blaming of the EPA for the rapid loss of agricultural wetlands; Lead industry's questioning of the scientific justification behind the decision of the EPA to lower the reporting threshold of lead and lead compounds.

Reports that the United States Environmental Protection Agency is expected to complete its risk management software tool in June 1999. Environmental Defense Fund's submission of a Freedom of Information Act to gain access to the software; Software's mimicking of risk assessment by calculating the size of Toxics Release Inventory chemicals, the dose to which they were exposed and the toxicity of the dose.

Reports on actions taken and rulings issued by the United States Environmental Protection Agency (EPA), as of May 1999. Civil rights investigation into the environmental and health concerns of African-American and Hispanic communities in New York City; Proposal of the relaxation of dumping rules for lead paint debris; Plan to focus more on `inert' ingredients in pesticides.

Reports on the petition filed by state governments and mine workers in the United States for a judicial review of a regulation placing nitrogen oxide emissions caps on 22 states. United Mine Workers of America's criticism against eight-hour ozone standard rule; Environmental Protection Agency's plan to review the emissions from other states.

Reports on the United States Environmental Protection Agency Office of Compliance Enforcement's expansion of the access to online environmental regulations. Establishment of compliance assistance centers; Budget allocated by Congress for the project; Benefits to be gained by small- and medium-sized companies from online regulation availability.

Presents news briefs from the United States (U.S.) Environmental Protection Agency (EPA). Reassessment of auto emissions standards; Controversy over a proposed Internet containing toxic release information; Reference to an evaluation of control technologies. INSETS: Agency-wide plan to reduce mercury releases;Unpublished health effects data sought for IRIS.

Presents a variety of information pertaining to the United States Environmental Protection Agency (EPA), as of February 1998. Reference to EPA setting standards for acceptable levels of arsenic in drinking water; Information on an EPA five-year Strategic Plan; Details on a draft agreement in order for state agencies to develop regulatory innovation proposals; Other news.

Presents news briefs pertaining to the United States Environmental Protection Agency (EPA), as of January 1998. Status of the approval of the nation's first transuranic radioactive waste storage facility in New Mexico; Support received by the EPA from companies pertaining to the use of alternative monitoring methods; Details on an agreement signed between the EPA and the metal-finishing industry regarding hazardous waste emissions; Other news. INSET: High-risk drinking water contaminants identified.

Presents news briefs pertaining to the Environmental Protection Agency, with reference to an agreement on a range of measures they used to determine the failure or success of environmental programs. What is the aim of the program; How government should avoid locating hazardous waste facilities near environmentally sensitive areas.