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1.
Abstract

This report discusses the responsibilities of government for the legislation of pesticides, and describes the impact of various statutes on the use of pesticides in agriculture. Governmental responsibilities for management of the economy, education, and enactment of laws and regulations are discussed, and the history of U.S. legislation of pesticides and related substances is presented. Finally, the impact of pesticide regulation on international trade is considered.  相似文献   

2.
Abstract

In the last few years, marked progress has been made in the development of methods for evaluating the mutagenic and carcinogenic potential of pesticide chemicals. The correlation of genetic and related biological activity in short‐term tests with carcinogenic activity in whole animals allows the utilization of short‐term mutagenicity bioassays to prescreen chemicals for effects related to mutation induction and presumptive carcinogenicity. In addition, bioassays now available can measure directly the chemical transformation of normal cells in culture into cells capable of producing tumors when injected into animals.

This paper will review briefly the major types of relevant short‐term tests and will develop a rationale for a phased approach to the evaluation of the mutagenic and carcinogenic potential of environmental chemicals. This approach involves the sequential application of bioassays which are organized into a three‐level matrix emphasizing first detection, then confirmation, and finally hazard assessment. Chemicals demonstrating positive results in the short‐term detection systems and confirmatory bioassays are pursued in higher level whole animal tests. A core battery of tests is proposed to operationally define a negative result. The phased approach should facilitate a cost effective utilization of limited testing resources and provide protection for human health in proportion to the anticipated hazard.

Results obtained in evaluating a series of thirty‐eight pesticide chemicals according to the phased approach are discussed in detail.  相似文献   

3.
Abstract

In an earlier paper the ozone-forming potential of n-propyl bromide (NPB) was studied with a new methodology designed to address issues associated with a marginal smog-forming compound. However, the U.S. Environmental Protection Agency (EPA) subsequently revised its policy and now recommends using the Maximum Incremental Reactivity (MIR) scale to rank the ozone-forming potential of all volatile organic compounds (VOCs), including those of marginal ozone productivity. Nevertheless, EPA contemplated exceptions to the box-model-derived MIR scale by allowing use of photochemical grid-model simulations for case specific reactivity assessments. The California Air Resources Board (CARB) also uses the MIR scale and CARB has a Reactivity Scientific Advisory Committee that can consider exceptions to the MIR scale. In this study, grid-model simulations that were recommended by EPA are used to evaluate the incremental ozone impacts of NPB using an update to the chemical mechanism developed in an earlier paper. New methods of analysis of the grid-model output are further developed here to quantify the relative reactivities between NPB and ethane over a wide range of conditions. The new grid-model-based analyses show that NPB is significantly different and generally less in ozone-forming potential (i.e., reactivity) than predicted by the box-model-based MIR scale relative to ethane, EPA’s “bright-line” test for non-VOC status. Although NPB has low reactivity compared to typical VOCs on any scale, the new grid-model analyses developed here show that NPB is far less reactive (and even has negative reactivity) compared to the reactivity predicted by the MIR scale.  相似文献   

4.
ABSTRACT

Based on the available evidence of health effects, the U.S. Environmental Protection Agency (EPA) has been evaluating the need to regulate mercury releases to the environment. In response to the congressional mandates in The 1990 Clean Air Act Amendments (CAAA), the EPA has issued the Mercury Study Report and the Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units Report. In spite of the enormous effort represented by these reports, as well as the efforts of both the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI), in conducting the field measurement programs that form the basis for these reports, a definitive answer on the need for mercury regulation has not been found. However, the EPA, as well as other regulatory agencies and health researchers, have suggested a "plausible link" between anthropogenic sources emitting mercury and the methylation, bioaccumulation in the food chain, and adverse health effects in humans and wildlife.  相似文献   

5.
Abstract

Consumer products are potentially significant sources of volatile organic compounds (VOCs), which are precursors to the formation of ozone in photochemical smog. To address the problem of ozone formation in ambient air, the U.S. Environmental Protection Agency (EPA) has been involved in the development of test methods for measuring the VOC content of consumer products. This paper describes results of an interlaboratory study to estimate the repeatability (precision of analyses performed by a single laboratory) and reproducibility (precision of analyses performed by different laboratories) of the consumer products’ VOC measurement method based on EPA Method 24 (for VOCs in surface coatings).

The mean method repeatability was 2.7 wt % VOC, and the mean method reproducibility was 4.8 wt % VOC. Method repeatability ranged from 0.2 to 4.4 wt % VOC, and reproducibility ranged from 0.6 to 11.9 weight percent VOC. The precision of the VOC method for consumer

products is similar to the precision of EPA Method 24 for surface coatings.  相似文献   

6.
ABSTRACT

Based on the available evidence of health effects, the U.S. Environmental Protection Agency (EPA) has been evaluating the need to regulate mercury releases to the environment. In response to the congressional mandates in The 1990 Clean Air Act Amendments (CAAA), the EPA has issued the Mercury Study Report and the Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units Report. In spite of the enormous effort represented by these reports, as well as the efforts of both the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI), in conducting the field measurement programs that form the basis for these reports, a definitive answer on the need for mercury regulation has not been found. However, the EPA, as well as other regulatory agencies and health researchers, have suggested a “plausible link” between anthropogenic sources emitting mercury and the methylation, bioaccumulation in the food chain, and adverse health effects in humans and wildlife.

Policy-makers have recognized that regulations must be based on good science and that a number of issues still remain. These issues can generally be grouped into four main categories: emissions inventory, control technology, fate of releases, and health effects. This paper will discuss recent, ongoing, and planned studies to address the remaining issues regarding the presence of mercury in the environment, with an emphasis on those studies that are directly related to the DOE/Federal Energy Technology Center’s (FETC) programmatic effort.  相似文献   

7.
Abstract

The Interagency Monitoring of Protected Visual Environments (IMPROVE) equation used to assess compliance under the U.S. Environmental Protection Agency (EPA) Haze Rule assumes that dry mass scattering efficiencies for aerosol chemical components are constant. However, examination of aerosol size distributions and chemical composition during the Big Bend Regional Aerosol and Visibility Observational Study and the Southeastern Aerosol and Visibility Study suggests that volume and mass scattering efficiencies vary directly with increasing particle light scattering and aerosol mass concentration. This is consistent with the observation that particle distributions were shifted to larger sizes under more polluted conditions and appears to be related to aging of the aerosol during transport to remote locations.  相似文献   

8.
Abstract

U.S. Environmental Protection Agency (EPA) Emission Measurement Center in conjunction with EPA Regions VI and VIII, the state of Utah, and the U.S. Department of Defense have conducted a series of long-term pilot and field tests to determine the accuracy and reliability of a visible opacity monitoring system consisting of a conventional digital camera and a separate computer software application for plume opacity determination. This technology, known as the Digital Opacity Compliance System (DOCS), has been successfully demonstrated at EPA-sponsored Method-9 “smoke schools,” as well as at a number of government and commercially operated industrial facilities.

Results from the current DOCS regulatory pilot study demonstrated that, under regulatory enforcement conditions, the average difference in opacity measurement between the DOCS technology and EPA Reference Method 9 (Method 9) was 1.12%. This opacity difference, which was computed from the evaluation of 241 regulated air sources, was found to be statistically significant at the 99% confidence level. In evaluating only those sources for which a nonzero visible opacity level was recorded, the average difference in opacity measurement between the DOCS technology and Method 9 was 1.20%. These results suggest that the two opacity measurement methods are essentially equivalent when measuring the opacity of visible emissions.

Given the costs and technical limitations associated with use of Method 9, there is a recognized need to develop accurate, reproducible, and scientifically defensible alternatives to the use of human observers. The use of digital imaging/processing brings current technology to bear on this important regulatory issue. Digital technology offers increased accuracy, a permanent record of measurement events, lower costs, and a scientifically defensible approach for opacity determination.  相似文献   

9.
Abstract

After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, the remaining low-activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation before being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile, and pesticide compounds and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River National Laboratory. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using U.S. Environmental Protection Agency (EPA) SW-846 Methods. Volatile and light semi-volatile organic compounds (<220 °C BP, >1 mm Hg vapor pressure) in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program (licensed by OLI Systems, Inc.) evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate, and off-gas streams, with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI Environmental Simulation Program model is constrained by available literature data.  相似文献   

10.
Abstract

The main objective of this study was to monitor the volatile organic compounds (VOCs) in the stack gas released from organic chemical industrial plants to determine emission factors. Samples from 52 stacks, with or without air pollution control devices (APCDs), from seven industrial processes were taken and VOCs measured using U.S. Environmental Protection Agency (EPA) Method 18. These 7 processes, including 26 plants, were the manufacturers of acrylonitrile–butadiene–styrene (ABS), polyvinyl chloride (PVC), polystyrene (PS), acrylic resin (ACR), vinyl chloride (VC), para–terephthalic acid (PTA), and synthetic fiber (SYF). The results clearly indicate significant variations of emission factors among the various industrial processes, particularly emission factors for those without APCDs. As expected, those with APCDs yield much less emission factors. Regardless of those with or without APCDs, the order of manufacturing processes with regard to VOC emission factors is SYF > ABS > PS > ACR > PTA > PVC > VC. The emission factors for some processes also differ from those in EPA–42 data file. The VOC profiles further indicate that some VOCs are not listed in the U.S. VOC/Particulate Matter Speciation Data System (SPECIATE). The potential O3 formation is determined from the total amount of VOC emitted for each of seven processes. The resultant O3 yield varied from 0.22 (ACR) to 2.33 g O3 g–1 VOC (PTA). The significance of this O3 yield is discussed.  相似文献   

11.
Abstract

The U.S. Environmental Protection Agency (EPA) developed and implemented the Acid Rain Program (ARP), and NOx Budget Trading Programs (NBTP) using several fundamental monitoring, reporting, and verification (MRV) elements: (1) compliance assurance through incentives and automatic penalties; (2) strong quality assurance (QA); (3) collaborative approach with a petition process; (4) standardized electronic reporting; (5) compliance flexibility for low-emitting sources; (6) complete emissions data record required; (7) centralized administration; (8) level playing field; (9) publicly available data; (10) performance-based approach; and (11) reducing conflicts of interest. Each of these elements is discussed in the context of the authors’ experience under two U.S. cap-and-trade programs and their potential application to other capand-trade programs.

The U.S. Office of Management and Budget found that the Acid Rain Program has accounted for the largest quantified human health benefits of any federal regulatory program implemented in the last 10 yr, with annual benefits exceeding costs by >40 to 1. The authors believe that the elements described in this paper greatly contributed to this success. EPA has used the ARP fundamental elements as a model for other cap-and-trade programs, including the NBTP, which went into effect in 2003, and the recently published Clean Air Interstate Rule and Clean Air Mercury Rule. The authors believe that using these fundamental elements to develop and implement the MRV portion of their cap-and-trade programs has resulted in public confidence in the programs, highly accurate and complete emissions data, and a high compliance rate (>99% overall).  相似文献   

12.
Abstract

Three different coals and an activated carbon were mixed with prescribed amounts of a sandy loam soil and added to soil columns to test their ability to retard pesticide movement. The pesticides chosen were prometon, prometryn, 2,4‐D, carbofuran, dinoseb, fenamiphos, and two oxidation products of fenamiphos, fenamiphos sulfoxide, and fenamiphos sulfone. These compounds were chosen to represent different chemical classes of pesticides and because they were considered to have a high potential for transport in soils. All the coals were more effective in retaining the pesticides than the soil, however, some were more effective than others. One of the coals was the most effective in retaining the majority of the pesticides with an overall retention of 94.7% in a 4:1 soil/coal ratio compared to the soil only with a retention of 48.5%. The moisture content of the coal appears to have a positive correlation with the ability of the coal to retain the pesticides under the conditions used for this experiment.  相似文献   

13.
Abstract

This paper reviews the development of pesticides as an agricultural and health tool and discusses the national and international implications of pesticide regulation. The need for scientific input to the legislative and regulative processes is explained. Appropriate legislation and regulatory structures are presented. Finally, the need for international cooperation in the use and control of pesticides is analyzed.  相似文献   

14.
ABSTRACT

A new technology for monitoring airborne heavy metals on aerosols and particulates based on spark-induced breakdown spectroscopy (SIBS) was evaluated at a joint U.S. Environmental Protection Agency (EPA)/U.S. Department of Energy test at the rotary kiln incinerator simulator (RKIS) facility at EPA/Research Triangle Park, NC, in September 1997. The instrument was configured to measure lead and chromium in a simulated combustion flue gas in real time and in situ at target levels of 15 and 75 u, g/dry standard cubic meters. Actual metal concentrations were measured during the tests using EPA Reference Method (RM) 29.

The SIBS technology detected both lead and chromium at the low- and high-level concentrations. Additionally, the hardware performed without failure for more than 100 hr of operation and acquired data for 100% of the RM tests. The chromium data were well correlated with concentration increases resulting from duct operations and pressure fluctuations that are known to entrain dust.  相似文献   

15.
Abstract

Nine different C18 solid‐phase extraction (SPE) cartridges were evaluated for their efficiency at extracting nine pesticides and two s‐triazine metabolites from spiked deionized water samples. The SPE cartridges were found to contain nitrogen (N) and/or phosphorus (P) contaminants and varied in their extraction efficiency for certain pesticides and metabolites. Four of the nine SPE cartridges gave acceptable (70 to 120%) pesticide and metabolite recovery percentages, while five cartridges had marginal (50 to 70%) to poor (< 50%) recoveries. Statistical analyses showed that the poor to marginal recoveries found for three compounds could not be explained by considering several indigenous chemical and physical traits of the cartridge. It is suggested that proper SPE cartridge selection for pesticide recovery should be evaluated using several different cartridges.  相似文献   

16.
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   

17.
Abstract

An activated charcoal bed unit (ACBU) was constructed using teflon stock. The unit duplicated the flow and bed design of a commercially available tractor mounted filter for removing pesticides from the air.

Eight pesticides (4 herbicides and 4 insecticides) were used to test the retention efficiency of ACBU over a 12–48 h period with the ACBU in place. Polyurethane foam (PUF) plugs in series trapped any residual pesticide that came through the ACBU.

The ACBU retained 93–100% of the pesticides tested. The unit thus provides an efficient mechanism for removing airborne pesticides.  相似文献   

18.
Abstract

This paper reports on the estimated potential air emissions, as found in air permits and supporting documentation, for seven of the first group of precommercial or “demonstration” cellulosic ethanol refineries (7CEDF) currently operating or planning to operate in the United States in the near future. These seven refineries are designed to produce from 330,000 to 100 million gal of ethanol per year. The overall average estimated air emission rates for criteria, hazardous, and greenhouse gas pollutants at the 7CEDF are shown here in terms of tons per year and pounds per gallon of ethanol produced. Water use rates estimated for the cellulosic ethanol refineries are also noted. The air emissions are then compared with similar estimates from a U.S. cellulosic ethanol pilot plant, a commercial Canadian cellulosic ethanol refinery, four commercial U.S. corn ethanol refineries, and U.S. petroleum refineries producing gasoline. The U.S. Environmental Protection Agency (EPA) air pollution rules that may apply to cellulosic ethanol refineries are also discussed. Using the lowest estimated emission rates from these cellulosic ethanol demonstration facilities to project air emissions, EPA’s major source thresholds for criteria and hazardous air pollutants might not be exceeded by cellulosic ethanol refineries that produce as high as 25 million gal per year of ethanol (95 ML). Emissions are expected to decrease at cellulosic ethanol refineries as the process matures and becomes more commercially viable.  相似文献   

19.
Abstract

The wide‐spread use of pesticides in modern agriculture has created a need to investigate the chemical transformation of pesticides in plants and animals. This paper reviews the chemical and biochemical fate of various pesticides and other xenobiotics. Photochemical mechanisms appear to be the most common pathways for the abiotic transformation of these chemicals. Biotic transformation includes a large group of biochemical reactions which may result in either deactivation (detoxication) or activation (toxication) of bioactive compounds. The need for quality control in the production of pesticides is also discussed.  相似文献   

20.
ABSTRACT

Three commercially available conversion varnish coating “systems” (stain, sealer, and topcoat) were selected for an initial scoping study. The total volatile content of the catalyzed varnishes, as determined by U.S. Environmental Protection Agency (EPA) Method 24, ranged from 64 to 73 weight%. Uncombined (free) formaldehyde concentrations, determined by a sodium sulfite titration method, ranged from 0.15 to 0.58 weight% of the uncatalyzed varnishes. Each sealer and topcoat was also analyzed by gas chromatography (EPA Method 311). The primary volatile organic constituents included methyl ethyl ketone (MEK), isobutanol, n-butanol, methyl isobutyl ketone (MIBK), toluene, ethylbenzene, the xylenes, and 1,2,4-trimethylbenzene.  相似文献   

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