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1.
ABSTRACT

Exposures from indoor environments are a major issue for evaluating total long-term personal exposures to the fine fraction (<2.5μm in aerodynamic diameter) of particulate matter (PM). It is widely accepted in the indoor air quality (IAQ) research community that biocontamination is one of the important indoor air pollutants. Major indoor air biocontaminants include mold, bacteria, dust mites, and other antigens. Once the biocontaminants or their metabolites become airborne, IAQ could be significantly deteriorated. The airborne biocontaminants or their metabolites can induce irritational, allergic, infectious, and chemical responses in exposed individuals.

Biocontaminants, such as some mold spores or pollen grains, because of their size and mass, settle rapidly within the indoor environment. Over time they may become nonviable and fragmented by the process of desiccation. Desiccated nonviable fragments of organisms are common and can be toxic or allergenic, depending upon the specific organism or organism component. Once these smaller and lighter fragments of biological PM become suspended in air, they have a greater tendency to stay suspended. Although some bioaerosols have been identified, few have been quantitatively studied for their prevalence within the total indoor PM with time, or for their affinity to penetrate indoors.

This paper describes a preliminary research effort to develop a methodology for the measurement of nonvi-able biologically based PM, analyzing for mold and ragweed antigens and endotoxins. The research objectives include the development of a set of analytical methods and the comparison of impactor media and sample size, and the quantification of the relationship between outdoor and indoor levels of bioaerosols. Indoor and outdoor air samples were passed through an Andersen nonviable cascade impactor in which particles from 0.2 to 9.0 um were collected and analyzed. The presence of mold, ragweed, and endotoxin was found in all eight size ranges. The presence of respirable particles of mold and pollen found in the fine particle size range from 0.2 to 5.25 um is evidence of fragmentation of larger source particles that are known allergens.  相似文献   

2.
Quality Assurance has been defined in many different ways to express concern for the “quality” of the output of some operation or function. For the purpose of this presentation, quality assurance is defined as the sum of those activities within an environmental monitoring or measurement program which are primarily for the purpose of documenting the precision, accuracy, representativeness, and completeness of the data that are produced. Further, we view quality assurance as a management tool which encompasses both administrative and technical functions which generally fall into three categories: (1) Prevention which includes those activities carried out prior to the proper placement and operation of the measurement system; (2) Evaluation which includes the continuous overview and checks on the performance of the systems and operators; and (3) Correction which includes changes made to improve or stabilize the capability and performance of the system.  相似文献   

3.
In 1986, the Federal Technology Transfer Act (FTTA) was established to promote a closer, collaborative relationship between federal government agencies and the private sector. With the increasing need for new cost-effective technologies to prevent and control pollution, both the U.S. Environmental Protection Agency and private industry are encouraged to facilitate the transfer of knowledge and technology under this Act. The FTTA removed several of the legal and institutional barriers to cooperative research that existed before the Act's passage. Through the FTTA, the government strives to promote the movement of its products, processes, skills and knowledge into the private sector for further development and commercialization by encouraging the exchange of technical personnel and the sharing of facilities and other resources. Collaborative efforts among industry, federal agencies and academia are made possible through cooperative research and development agreements (CRDAs). Thirty-three CRDAs and four licensing agreements have been initiated with EPA under the program. This paper provides an overview of this new and innovative program.  相似文献   

4.
The 1990 Clean Air Act Amendments added a new Title V to the Act which establishes an operating permit program for numerous sources of air pollution. Certain sources are currently required to obtain a construction or “new source review” permit; the 1990 Amendments will require many more sources to apply for a permit which will give them permission to operate. CAA Title V was modeled on the National Pollutant Discharge Elimination System (NPDES) permit provisions of the Clean Water Act, but there are important differences between the two statutes.

Although many states already have their own operating permit programs, by late 1993 every state must establish a program that meets the requirements of Title V and EPA’s implementing regulations. EPA recently proposed these regulations, and by the statutory deadline of November 15, 1991 hopes to issue final regulations establishing the minimum elements of state operating permit programs. These regulations will significantly affect implementation of air pollution measures for years to come because a Title V operating permit will have to assure compliance with all applicable CAA requirements. In addition, permitted sources will be required to pay fees to cover the costs of the permit program.  相似文献   

5.
Abstract

A wide range of new and exciting highly time-resolved instruments were deployed during the U.S. Environmental Protection Agency (EPA) Supersite program and related studies that occurred during the same time period. These measurements elucidated the temporal variation of a suite of gas-phase species, particle physical properties, and size-resolved particulate chemical composition. Because the temporal resolution was so high, concentration and size distribution changes as short as 1 min or less were discerned. Often data from multiple instruments were correlated with each other and with meteorological measurements, and these correlations enabled conclusions to be drawn about the photochemical activity of the atmosphere, the location of point sources, and even the emissions characteristics of these sources. For instance, rapid changes in particulate matter (PM) concentration were due to meteorological conditions, emissions, and plume excursions that led to increases in nitrate, sulfate, and organic carbon concentrations. This paper summarizes the conclusions that have been reached, to date, using these new, highly time-resolved instruments, and demonstrates their promise for future studies.  相似文献   

6.
A fluoride analyzer originally designed by Wiggins, St. John, Thomas arid associates at Stanford Research Institute, has been modified to improve its operational capabilities and reliability so as to operate for periods in excess of six months with virtually no maintenance. It measures hydrogen fluoride in the atmosphere in the sub-parts per billion range. The need for the instrument, method of measuring fluoride and the modifications made to improve the SRI instrument are presented. The instrument has been operated in the field for two years beside impingers which obtain daily integrated samples. The impingers samples are subsequently titrated. Satisfactory correlation has been found between the average daily values by the automatic analyzer and the impinger.  相似文献   

7.
Title V of the Clean Air Act requires tens of thousands of air pollution sources to obtain an operating permit incorporating all applicable requirements under the Act. EPA recently promulgated its controversial Title V regulations, which establish the minimum elements for state permit programs.

The new permit system is among the most important changes made by the 1990 Clean Air Act Amendments, and will significantly alter the way companies comply with air pollution requirements. Previously, the Act only required certain sources to obtain a new source review permit before constructing or modifying the facility (although many states established operating permit systems on their own). Now, all states must adopt operating permit programs consistent with the minimum federal requirements, and submit them to EPA by November 1993. Even though EPA has established minimum requirements, these programs are likely to vary widely from state to state.  相似文献   

8.
The chemical and optical properties of particle emissions from onroad vehicles were investigated at the Allegheny Tunnel on the Pennsylvania Turnpike during July 1981. The optical results are in agreement with earlier data: (1) in terms of light extinction per km driven, diesel particle emissions are at least an order of magnitude more important than particle emissions from spark-ignition vehicles; (2) for diesel particle emissions, light absorption is about twice as efficient as light scattering. Chemical analyses showed that: (1) 24% of the vehicle aerosol was extractable material, (2) 75% of the total mass was carbon, (3) 55% of the total mass was unextractable (elemental) carbon, and (4) the stoichiometry of the extractable fraction of the diesel particle emissions was CnHt.7nN0.05n , i.e., the extractable material was composed predominantly of alkanes. The results of the chemical analyses allow the calculation of the massspecific light absorption coefficient for the elemental carbon component of the diesel particle emissions, i.e., 10.9 ± 1.8 m2/g (500 nm).  相似文献   

9.
10.
Under the Superfund Innovative Technology Evaluation (SITE) Program, a technology developed by AWD Technologies, Inc. was demonstrated in September 1990. This paper presents the major results of the SITE demonstration of AWD Technologies’ AquaDetox®ISVE treatment system designed for simultaneous on-site treatment of contaminated groundwater and soil-gas. The groundwater and soil at the demonstration site were contaminated with trichloroethylene (TCE) and tetrachloroethylene (PCE). The AWD technology was evaluated on the basis of the removal efficiencies of TCE and PCE from the contaminated groundwater and soil-gas. The conclusions drawn from these evaluations are: (1) the system achieved removal efficiencies as high as 99.99percent for groundwater and 99.9 percent for soil-gas; (2) the effluent groundwater was in compliance with the regulatory discharge requirements of 5 fig/L each for TCE and PCE for all test runs; (3) the demonstrated 1,000 gpm system has an estimated capital cost of $4.3 million and annual operating and maintenance cost of approximately $820,000.  相似文献   

11.
The Superfund Innovative Technology Evaluation (SITE) Emerging Technology Program (ETP) has encouraged and financially supported further development of bench- and pilot-scale testing and evaluation of innovative technologies suitable for use at hazardous waste sites for five years. The ETP was established under the Superfund Amendments and Reauthorization Act (SARA) of 1986. The ETP complies with the goal of the SITE Program to promote, accelerate and make commercially available the development ofalternative /innovative treatment technologies for use at Superfund sites.

Technologies are submitted to the ETP through yearly solicitations for Preproposals. Following a technical review, chosen applicants are asked to submit a detailed project proposal and a cooperative agreement application that requires Developer I EPA cost sharing. EPA co-funds selected Developers for one to two years. Second-year funding requires documentation of significant progress during the first year. Facilities, equipment, data collection, performance and development are monitored throughout the project. The U. S. Department of Energy (DOE) and the U. S. Air Force (USAF) are participants in the ETP. DOE has co-funded ETP projects since 1990 and the USAF since 1991.

A primary goal of the ETP is to move developed technologies to the field-demonstration stage. Therefore, a developer may be considered for participation in the SITE Demonstration Program provided performance in the ETP indicates the technology is field-ready for demonstration and evaluation.

Six technology categories: biological, chemical, materials handling, physical, solidification/ stabilization and thermal, are presently in the ETP.

Technologies of primary interest to EPA are those that can treat complex mixtures of hazardous organic and inorganic contaminants and provide improved solids handling and/orpretreatment.

An account of the background and progress of the ETP’s first five years is presented in this paper. Technologies currently in the ETP, including those selected from the fifth (EOS) solicitation, are noted, and developers, along with EPA Project Managers, are listed.  相似文献   

12.
Headquarters managers and Regional staff in the U.S. Environmental Protection Agency’s hazardous and solid waste programs were surveyed to determine priorities for technical information and guidance among EPA Regional staff, state hazardous waste management staff, EPA contractors, and the regulated community. The survey also examined delivery systems effective for EPA Regional staff. The fifteen highest ranked technical needs for RCRA, Superfund, and UST reflect a pervasive interest in hazardous waste remediation. Top priority technical needs focus on establishing cleanup levels, subsurface fate and transport, field monitoring and quality assurance, remedy selection, and most importantly, which remedies work and which do not in specific situations. Technical needs of non- EPA audiences are quite similar to those for EPA field staff. Preferences for technology transfer delivery systems are generally for conventional distribution methods (such as print materials and workshops) rather than electronic or video media. Regional staff report serious problems in utilizing technology transfer because of time constraints, insufficient knowledge of available products, insufficient travel funds, and limited access to and training on computers.  相似文献   

13.
Indoor radon has been judged to be the most serious environmental carcinogen which the EPA must address for the general public. The optimal strategy for dealing with this problem depends on the magnitude of the risk, how the risk is distributed within the population, as well as the effectiveness and costs of mitigation measures. Based on current exposure and risk estimates, radon exposure in single-family houses may be a causal factor in roughly 20,000 lung cancer fatalities per year. Most of these projected fatalities are attributable to exposures in houses with average or moderately elevated radon levels (below 10 pCi/L). Hence to appreciably reduce radon-induced lung cancers, remediation efforts must include houses not highly elevated in radon. From either an individual risk or a cost-benefit standpoint, reduction of a few pCi/L per home appears to be justified. The optimal strategy for dealing with the indoor radon problem depends on the magnitude of the risk per unit exposure, the distribution of exposures in houses, and the effectiveness and costs of mitigation. EPA’s current views with respect to these factors and the associated uncertainties are discussed.  相似文献   

14.
The Province passed an Air Pollution Control Act in 1958 which delegated control of all types of air pollution to the municipalities. This was amended in 1963 with the Province assuming control of industrial sources of air pollution and the municipalities retaining control of combustion sources. The paper outlines the comprehensive program adopted by the Province. It points out that while control is a primary function, other functions such as ambient air quality sampling, the collection of micro meteorological data, co-operation with other governmental agencies in agriculture, planning and zoning, economics and development, and water pollution are a vital part of the program. In light of the experience to date, an attempt is made to predict the organization necessary for the future.  相似文献   

15.
In New York State there is a tradition of teamwork between industry and government toward air pollution control programs. This was demonstrated initially when Associated Industries assisted in writing New York State’s Air Pollution Control Law. Industry in New York State has accepted a two-way responsibility for educating industry and the public. New York State’s Department of Public Health has organized an “Action for Clean Air” program and Associated Industries of New York has joined with official agencies in promoting the public information program to lessen the possibility of hysteria.  相似文献   

16.
A sulfuric acid review conference sponsored by EPA's automotive Catalyst Research Program was held recently at Hendersonville, NC, for researchers whose work is funded by EPA. Emissions characterization research indicated that in-use catalyst-equipped vehicles emit low levels of H2SO4, averaging 2.7 mg/mile for 49-state cars and 15 mg/mile for California cars. Research on measurement methodology for H2SO4 and other sulfate compounds has led to the development of several promising techniques based on selective volatilization. In-roadway and off-roadway monitoring programs are providing sulfate data which can lead to improved mathematical predictive models. Acute toxicity studies to date indicate that morphological, biochemical, physiological, and pharmacological alterations due to inhaled H2SO4 alone do not appear to occur at levels less than 1 mg/m3. However, striking effects are noted with combinations of H2SO4 and other pollutants. Participants identified the need for long term chronic H2SO4 exposure studies.  相似文献   

17.
Jack Valentin 《Ambio》2013,42(4):381-382
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18.
Under the SITE Emerging Technology Program, the U.S. Environmental Protection Agency is seeking to foster the further development of technologies that have been successfully tested at bench-scale and are now ready for pilot-scale testing, prior to field- or full-scale demonstration. The goal is to ensure that a steady stream of permanent, cost-effective, technologies will be ready for demonstration in the field, thereby increasing the number of viable alternatives available for use in Superfund removal and remedial actions. Under this program, EPA can offer technology developers financial assistance of up to $150,000 per year, for up to two years. The program is in its second year with seven projects underway and eight more ready to start, pending completion of award actions. The Third Emerging Technology Program Solicitation is open to the receipt of new proposals from July 8,1989 through September 7,1989. The purpose of this article is to provide the reader with: (1) an introduction to the Emerging Technology Program; (2) an understanding of how the Program operates; (3) a summary of those technologies currently being tested and evaluated under the Program; and (4) information on how to apply to the Program.  相似文献   

19.
Environmental Science and Pollution Research - The microbiome is a term that usually refers to the community of various microorganisms that inhabit/live inside human/animal bodies or on their skin....  相似文献   

20.
Selection of acceptable sites for industrial facilities, especially hazardous waste management facilities, can be made using a relatively new technique referred to as “fuzzy set analysis.” The methodology presented is applicable to multiple alternative decision making, when criteria are of unequal importance, and is based on the concept of establishing a subjective value for each alternative according to each criterion, and then raising the subjective value to a power commensurate with the relative importance of the criterion. This exponential weight is calculated on the basis of a preferential analysis of criteria comparisons. Apart from the ranking of the alternatives, fuzzy set analysis provides a quantitative representation of the community opinion of the order of importance of the criteria, regardless of the sites being considered. Based on the importance factors averaged from a cross section of the community, public concern could also be ranked.  相似文献   

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