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[en] The Acceptable Daily Intake (ADI) has been used by regulatory and public health organizations (e.g., the U.S. Food and Drug and Administration, and the World Health Organization) for chemicals for more than 50 years. The ADI concept was also initially employed at the U.S. Environmental Protection Agency at its inception in 1971, although with the adoption of newer terminology, it later became known as the Reference Dose (RfD). It is clear from the literature that both were first devised as instruments of regulatory policy. In the intervening years, it has become common to use language that implies that these standards are statements of scientific fact. Similarly, some of the discretionary or default values that are used to derive regulatory standards are represented as scientific assumptions when in fact they also represent regulatory policy. This confusion impedes both the best use of the available science and informed public participation in policy making. In addition, the misconception of the ADI or the RfD as statements of scientific fact may impede the consideration of alternative means to reduce exposure to chemicals that may be harmful, including regulatory measures that do not involve prescribing a regulatory concentration limit.
[en] This report summarizes the results and rationale for radiological dose calculations for the maximally exposed individual during fusion accident conditions. Early doses per unit activity (Sieverts per TeraBecquerel) are given for 535 magnetic fusion isotopes of interest for several release scenarios. These data can be used for accident assessment calculations to determine if the accident consequences exceed Nuclear Regulatory Commission and Department of Energy evaluation guides. A generalized yearly dose estimate for routine releases, based on 1 Terabecquerel unit releases per radionuclide, has also been performed using averaged site parameters and assumed populations. These routine release data are useful for assessing designs against US Environmental Protection Agency yearly release limits
[en] This document provides guidance to generator groups for preparing and maintaining documentation of Pollution Prevention/Waste Minimization (P2/WMin) Program activities. The guidance is one of a hierarchical series that includes the Hanford Site Waste Minimization and Pollution Prevention Awareness Program Plan (DOE-RL, 1998a) and Prime Contractor implementation plans describing programs required by Resource Conservation and Recovery Act of 1976 (RCRA) 3002(b) and (300501) (RCRA and EPA, 1994). Documentation guidance for the following five P2/WMin elements are discussed: Fiscal Year (FY) Goals; Budget and Staffing; Waste Minimization (WMinn ) Assessments (WMAs); Pollution Prevention (P2) Reporting; WMin Certification
[en] Several of the most common methods for estimating Pasquill-Gifford (PG) stability (turbulence) class were evaluated for use in modeling the radiological consequences of SRS accidental releases using the MELCOR Accident Consequence Code System, Ver. 2 (MACCS2). Evaluation criteria included: (1) the ability of the method to represent diffusion characteristics above a predominantly forested landscape at SRS, (2) suitability of the method to provide data consistent with the formulation of the MACCS2 model, and (3) the availability of onsite meteorological data to support implementation of the method The evaluation resulted in a recommendation that PG stability classification for regulatory applications at SRS should be based on measurements of the standard deviation of the vertical component of wind direction fluctuations, σe, collected from the 61-m level of the SRS meteorological towers, and processed in full accordance with EPA-454/R-99-005 (EPA, 2000). This approach provides a direct measurement that is fundamental to diffusion and captures explicitly the turbulence generated by both mechanical and buoyant forces over the characteristic surface (forested) of SRS. Furthermore, due to the potentially significant enhancement of horizontal fluctuations in wind direction from the occurrence of meander at night, the use of σe will ensure a reasonably conservative estimate of PG stability class for use in dispersion models that base diffusion calculations on a single value of PG stability class. Furthermore, meteorological data bases used as input for MACCS2 calculations should contain hourly data for five consecutive annual periods from the most recent 10 years.
[en] The toxicity value database of the United States Environmental Protection Agency's (EPA) National Homeland Security Research Center has been in development since 2004. The toxicity value database includes a compilation of agent property, toxicity, dose-response, and health effects data for 96 agents: 84 chemical and radiological agents and 12 biotoxins. The database is populated with multiple toxicity benchmark values and agent property information from secondary sources, with web links to the secondary sources, where available. A selected set of primary literature citations and associated dose-response data are also included. The toxicity value database offers a powerful means to quickly and efficiently gather pertinent toxicity and dose-response data for a number of agents that are of concern to the nation's security. This database, in conjunction with other tools, will play an important role in understanding human health risks, and will provide a means for risk assessors and managers to make quick and informed decisions on the potential health risks and determine appropriate responses (e.g., cleanup) to agent release. A final, stand alone MS ACESSS working version of the toxicity value database was completed in November, 2007
[en] Traditionally, the No-Observed-Adverse-Effect-Level (NOAEL) approach has been used to determine the point of departure (POD) from animal toxicology data for use in human health risk assessments. However, this approach is subject to substantial limitations that have been well defined, such as strict dependence on the dose selection, dose spacing, and sample size of the study from which the critical effect has been identified. Also, the NOAEL approach fails to take into consideration the shape of the dose-response curve and other related information. The benchmark dose (BMD) method, originally proposed as an alternative to the NOAEL methodology in the 1980s, addresses many of the limitations of the NOAEL method. It is less dependent on dose selection and spacing, and it takes into account the shape of the dose-response curve. In addition, the estimation of a BMD 95% lower bound confidence limit (BMDL) results in a POD that appropriately accounts for study quality (i.e., sample size). With the recent advent of user-friendly BMD software programs, including the U.S. Environmental Protection Agency's (U.S. EPA) Benchmark Dose Software (BMDS), BMD has become the method of choice for many health organizations world-wide. This paper discusses the BMD methods and corresponding software (i.e., BMDS version 2.1.1) that have been developed by the U.S. EPA, and includes a comparison with recently released European Food Safety Authority (EFSA) BMD guidance.
[en] Full text: During June 2015, EPA’s Homeland Security Research Program (HSRP) demonstrated five wide-area radiological decontamination technologies (including strippable coatings, gels, and chemical foam technologies) on an urban building. Decontamination technologies were applied to remove the contaminants from surfaces by physical, chemical, or other methods to reduce radiation exposure level. In addition, NHSRC teamed with the Department of Homeland Security (DHS) to demonstrate several radiological mitigation technologies including building and vehicle wash technologies, as well as high- and low-technology particle and liquid containment technologies. Radiological contaminant mitigation technologies are measures taken to reduce adverse impacts of radiological contamination on people and the environment, and facilitate such purposes as restoration of first responder services and critical infrastructure. The purpose of the demonstrations was to showcase and provide education about a “Toolbox of Options” for radiological decontamination, as well as mitigation (specifically gross decontamination and containment). Both demonstrations were conducted using a 75-year old brick building and the surrounding area (including parking lots) in Columbus, OH. No radioactive contaminants were applied during either demonstration, as the objective was to duplicate and implement realistic operational conditions for these technologies. Surrogate contaminants such as particle tracers were used in several demonstrations. Example information that was obtained included decontamination rate and mitigation and containment capacity, user friendliness of each technology, the required utilities (electric, water, etc.) for each technology, skill of worker required, and the cost. The condition (color, texture, integrity, etc.) of each building material present on the structure along with all structural components such as gutters, windows, doors, etc. were carefully examined and documented. The decontamination technologies were used in a scaled-up setting with application to a multiple story building. Contaminant mitigation technologies were demonstrated on the building as well as on vehicles. Example technology application techniques/accessories included an articulating boom lift, repelling boatswain chair, stand-alone surface material structures, high-volume foam applicators, fire truck foam applicator, a vehicle wash tent for vehicles, particle tracers to simulate radiological contaminants, and high- and low-technology liquid containment approaches. All demonstrations were open to individuals, organizations, and local, state, federal, tribal, and international governments who may be involved with implementing or planning radiological incident response. (author)
[en] November 1971, page 37—The figure illustrating estimated radiation doses in Joseph Lieberman's article was credited to the Division of Criteria and Standards, Office of Radiation Programs of the Environmental Protection Agency. Lieberman tells us that the data presented there should be attributed to an interagency special‐studies group working with the Criteria and Standards division; the participating agencies were the Department of Defense, the Department of Health, Education and Welfare, the Atomic Energy Commission and the Environmental Protection Agency. Their final report is due to be issued in June.
[en] Corporate voluntary climate programs have had limited evaluation. The self-selection of participants—an essential element of such initiatives—poses challenges to researchers because the decision to participate may not be random and may be correlated with outcomes. This study aims to gage the environmental effectiveness of the industrial sector elements of two early voluntary climate change programs with established track records, the U.S. Environmental Protection Agency's Climate Wise and the U.S. Department of Energy's Voluntary Reporting of Greenhouse Gases Program (1605(b)). Particular attention is paid to the participation decision and how various assumptions affect estimates of program outcomes using propensity score matching methods applied to plant-level Census data. Overall, the effects are modest: reductions in fuel and electricity expenditures are no more than 10 percent and probably less than 5 percent. Virtually no evidence suggests either program has a statistically significant effect on fuel costs. Some evidence indicates that participation in Climate Wise led to a 3–5 percent increase in electricity costs that vanished after two years. Stronger evidence suggests that participation in 1605(b) led to a 4–8 percent decrease in electricity costs that persisted for at least three years. These results suggest that while voluntary programs can play some role in addressing climate change, they are unlikely to bring about the kinds of steep reductions called for in the current debate.