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Procedures and Equipment Used in Inhalation Studies on Small Animals

Description: From Introduction: "These facts prompted the initiation of an effort to develop appropriate exposure equipment. The purpose of this communication is first, to describe an apparatus which, with modifications, allows pertinent information to be obtained on each individual small animal exposed and secondly, to set forth the pre- and post-exposure procedure adopted for obtaining required quantitative data regarding respiration, deposition. distribution and excretion."
Date: September 1963
Creator: Thomas, R. G. & Lie, R.
Partner: UNT Libraries Government Documents Department

What is Known about the Effect of Smoke on Health

Description: From title page: "For some years the Bureau of Mines, in connection with its investigations relating to efficiency in the combustion of fuels, as been engaged in a study of smoke prevention. Popular support for such work is usually based upon the injurious effects of smoke on the human ssytem, and this paper is published as a contribution to the literature dealing with that subject."
Date: December 7, 1926
Creator: White, William Charles
Partner: UNT Libraries Government Documents Department

Why We Ventilate

Description: It is widely accepted that ventilation is critical for providing good indoor air quality (IAQ) in homes. However, the definition of"good" IAQ, and the most effective, energy efficient methods for delivering it are still matters of research and debate. This paper presents the results of work done at the Lawrence Berkeley National Lab to identify the air pollutants that drive the need for ventilation as part of a larger effort to develop a health-based ventilation standard. First, we present results of a hazard analysis that identified the pollutants that most commonly reach concentrations in homes that exceed health-based standards or guidelines for chronic or acute exposures. Second, we present results of an impact assessment that identified the air pollutants that cause the most harm to the U.S. population from chronic inhalation in residences. Lastly, we describe the implications of our findings for developing effective ventilation standards.
Date: September 1, 2011
Creator: Logue, Jennifer M.; Sherman, Max H.; Price, Phil N. & Singer, Brett C.
Partner: UNT Libraries Government Documents Department

A review of Plutonium (Pu) combustion releases in air for inhalation hazard evaluation.

Description: Experimental data are compiled and reviewed for aerosol particle releases due to combustion in air of Plutonium (Pu). The aerosol release fraction (ARF), which is the mass of Pu aerosolized, divided by the mass of Pu oxidized, is dependent on whether the oxidizing Pu sample is static (i.e. stationary) or dynamic (i.e. falling in air). ARF data are compiled for sample masses ranging from 30 mg to 1770 g, oxidizing temperatures varying from 113 C to {approx}1000 C, and air flow rates varying from 0.05 m/s to 5.25 m/s. The measured ARFs range over five orders of magnitude. The maximum observed static ARF is 2.4 x 10{sup -3}, and this is the recommended ARF for safety studies of static Pu combustion.
Date: September 1, 2003
Creator: McClellan, Yvonne; Murata, Kenneth K. & Gelbard, Fred
Partner: UNT Libraries Government Documents Department

Plutonium 239 Equivalency Calculations

Description: This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.
Date: May 31, 2011
Creator: Wen, J
Partner: UNT Libraries Government Documents Department

The Reutter/Wade Toxicity Report and CSEPP Civilian Emergency Planning

Description: The Reutter/Wade analysis (Reutter and Wade 1994) was undertaken to improve the technical basis for assessing battlefield casualties from deployment of chemical weapons containing nerve and sulfur mustard agent payloads. The analysis sought to utilize available data and modern, accepted, toxicological methods to develop agent-specific casualty estimators for U.S. military forces. The authors also estimated qualitative confidence levels for each estimator based on the quality and quantity of the data. For percutaneous and inhalation vapor exposures, the report estimated cumulative exposures necessary to achieve lethal (LCt{sub 50}), severe (ED{sub 50}), threshold (percutaneous vapor only, ECt{sub 50}), or mild (nasal vapor, ECt{sub 50}) effects. For percutaneous liquid exposures, the report estimated lethal (LD{sub 50}) and severe (ED{sub 50}) doses. The vapor exposures necessary to achieve mild ocular effects were also estimated. This report examines potential implications of the Reutter/Wade study for off-site or civilian emergency planning in the Chemical Stockpile Emergency Preparedness Program (CSEPP) and summarizes principal findings of the Reutter/Wade report, the National Academy review of Reutter/Wade, and the Institute for Defense Analysis (IDA) expert panel assessment of Reutter/Wade casualty estimators. This report also identifies how estimates of human health effects are used in CSEPP, organized by functional planning topics. Finally CSEPP casualty estimators are considered in light of the Reutter/Wade work.
Date: August 4, 1999
Creator: Sorensen, J.H.
Partner: UNT Libraries Government Documents Department

Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

Description: Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.
Date: September 10, 2003
Creator: Leggett, R.W.
Partner: UNT Libraries Government Documents Department

Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

Description: This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intake or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many ...
Date: October 1, 2008
Creator: Leggett, Richard Wayne; Eckerman, Keith F & Meck, Robert A.
Partner: UNT Libraries Government Documents Department

Post-accident inhalation exposure and experience with plutonium

Description: This paper addresses the issue of inhalation exposure immediately afterward and for a long time following a nuclear accident. For the cases where either a nuclear weapon burns or explodes prior to nuclear fission, or at locations close to a nuclear reactor accident containing fission products, a major concern is the inhalation of aerosolized plutonium (Pu) particles producing alpha-radiation. We have conducted field studies of Pu- contaminated real and simulated accident sites at Bikini, Johnston Atoll, Tonopah (Nevada), Palomares (Spain), Chernobyl, and Maralinga (Australia).
Date: June 1, 1998
Creator: Shinn, J
Partner: UNT Libraries Government Documents Department

Inhalation Toxicology Research Institute Site Environmental report, 1994

Description: The Inhalation Toxicology Research Institute (ITRI) was constructed in 1960 with the initial purpose of studying human health hazards of inhaling airborne radioactive fission products; its scope was broadened to cover other airborne materials. ITRI has in place an extensive radiological and nonradiological environmental monitoring program which monitors air emissions, groundwater, soil and ambient air around the facility. ITRI is in compliance with air quality and hazardous waste regulations; however, sewage lagoons remain from previous operations. Remediation activities have been begun or are scheduled to begin on these lagoons and on low-level radioactive liquid waste evaporation ponds. Except for the issues mentioned, ITRI is in compliance with all other federal, state, and local regulations.
Date: May 1, 1995
Partner: UNT Libraries Government Documents Department

NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

Description: This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and coal. The objective is to determine the relationship between (1) fraction sludge in the sludge/coal mixture, and (2) combustion conditions on (a) NOx concentrations in the exhaust, (b) the size segregated fine and ultra-fine particle composition in the exhaust, and (c) the partitioning of toxic metals between vapor and condenses phases, within the process. The proposed study will be conducted in concert with an existing ongoing research on toxic metal partitioning mechanisms for very well characterized pulverized coals alone. Both high NOx and low NOx combustion conditions will be investigated (unstaged and staged combustion). Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. Previous research results have demonstrated that the inhalation of coal/MSS ash particles cause an increase in lung permeability than coal ash particles alone. Elemental analysis of the coal/MSS ash particles showed that Zn was more abundant in these ash particles than the ash particles of coal ash alone.
Date: January 31, 2003
Creator: Wendt, Jost O. L.
Partner: UNT Libraries Government Documents Department

Aspiration tests in aqueous foam using a breathing simulator

Description: Non-toxic aqueous foams are being developed by Sandia National Laboratories (SNL) for the National Institute of Justice (NIJ) for use in crowd control, cell extractions, and group disturbances in the criminal justice prison systems. The potential for aspiration of aqueous foam during its use and the resulting adverse effects associated with complete immersion in aqueous foam is of major concern to the NIJ when examining the effectiveness and safety of using this technology as a Less-Than-Lethal weapon. This preliminary study was designed to evaluate the maximum quantity of foam that might be aspirated by an individual following total immersion in an SNL-developed aqueous foam. A.T.W. Reed Breathing simulator equipped with a 622 Silverman cam was used to simulate the aspiration of an ammonium laureth sulfate aqueous foam developed by SNL and generated at expansion ratios in the range of 500:1 to 1000:1. Although the natural instinct of an individual immersed in foam is to cover their nose and mouth with a hand or cloth, thus breaking the bubbles and decreasing the potential for aspiration, this study was performed to examine a worst case scenario where mouth breathing only was examined, and no attempt was made to block foam entry into the breathing port. Two breathing rates were examined: one that simulated a sedentary individual with a mean breathing rate of 6.27 breaths/minute, and one that simulated an agitated or heavily breathing individual with a mean breathing rate of 23.7 breaths/minute. The results of this study indicate that, if breathing in aqueous foam without movement, an air pocket forms around the nose and mouth within one minute of immersion.
Date: December 1, 1995
Creator: Archuleta, M.M.
Partner: UNT Libraries Government Documents Department

Validation of protection provided by one brand of filtering facepiece respirator

Description: A previous laboratory study of a widely used disposable dust / mist (D/M) respirator (3M{trademark}8710) utilized a challenge agent that had high penetration values for D/M filter media. Therefore, measured protection factors (PFs) reflected both filter and faceseal penetration, and would be lower than that expected for faceseal penetration only. The purpose of this study was to determine a PF for this brand of disposable D/M respirator using a challenge agent that has low filter penetration for this type of filter. Methodology involved qualitatively (QLFT) and quantitatively (QNFT) fit testing 15 males and 15 females while wearing the respirator. One QLFT was done per subject using the saccharin method. Three QNFTs were performed on each subject utilizing a 2.5 {mu}m mass median aerodynamic diameter (MMAD) monodisperse challenge aerosol. Measured PF`s were corrected for lung deposition of this size aerosol. The average fit for each subject was the arithmetic mean of the three PFs. The PFs were found to be approximately log-normally distributed, so logs of PFs were used in the statistical analysis. The exponent of the 95% lower tolerance level (LTL) of the fifth percentile of the log PFs was 50. This compares to an exponent of the 95% LTL of the fifth percentile of the log PFs of two determined in a previous study and to the American National Standards Institute (ANSI) Assigned Protection Factor (APF) of ten. No significant difference of average fit between males and females was found. The sensitivity of the saccharin QLFT was 42.9%, and specificity could not be evaluated.
Date: May 1, 1995
Creator: Peacock, J.R.
Partner: UNT Libraries Government Documents Department

Assessing inhalation exposure from airborne soil contaminants

Description: A method of estimation of inhalation exposure to airborne soil contaminants is presented. this method is derived from studies of airborne soil particles with radioactive tags. The concentration of contaminants in air (g/m{sup 3}) can be derived from the product of M, the suspended respirable dust mass concentration (g/m{sup 3}), S, the concentration of contaminant in the soil (g/g), and E{sub f}, an enhancement factor. Typical measurement methods and values of M, and E{sub f} are given along with highlights of experiences with this method.
Date: April 1, 1998
Creator: Shinn, J.H.
Partner: UNT Libraries Government Documents Department

Silica exposure to excavation workers during the excavation of a low level radiological waste pit and tritium disposal shafts

Description: This study evaluated the task-length average (TLA) respirable dust and respirable silica airborne concentrations to which construction workers excavating volcanic tuff at Los Alamos National Laboratory (LANL) were exposed. These workers were excavating a low level radiological waste disposal pit of final dimensions 720 feet long, 132 feet wide and 60 feet deep. The objectives of this study were as follows: (1) evaluate exposures; (2) determine if the type of machinery used affects the respirable dust concentration in the breathing zone of the worker; (3) evaluate the efficacy of wetting the pit to reduce the respirable dust exposure; and (4) determine if exposure increases with increasing depth of pit due to the walls of the pit blocking the cross wind ventilation.
Date: January 1, 1995
Creator: Wilson, K.M.
Partner: UNT Libraries Government Documents Department

Tank Waste Remediation System Resolution of Potentially Hazardous Tank Vapor Issues

Description: This report documents the resolution of industrial health and safety issues regarding potentially hazardous tank vapors in the Hanford 200 Area Tank Farms. It also summarizes the tasks and controls which have been implemented and demonstrates that with the present work controls in place, an unacceptable inhalation risk to workers from tank farm vapors does not exist.
Date: July 10, 1996
Creator: Hewitt, E.R., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Y-12 Uranium Exposure Study

Description: Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.
Date: August 5, 1999
Creator: Eckerman, K.F. & Kerr, G.D.
Partner: UNT Libraries Government Documents Department

Classification of poison inhalation hazard materials into severity groups

Description: Approximately 1.5 billion tons of hazardous materials (hazmat) are transported in the US annually, and most reach their destinations safely. However, there are infrequent transportation accidents in which hazmat is released from its packaging. These accidental releases can potentially affect the health of the exposed population and damage the surrounding environment. Although these events are rare, they cause genuine public concern. Therefore, the US Department of Transportation Research & Special Programs Administration (DOT- RSPA) has sponsored a project to evaluate the protection provided by the current bulk (defined as larger than 118 gallons) packagings used to transport materials that have been classified as Poison Inhalation Hazards (PIH) and recommend performance standards for these PIH packagings. This project was limited to evaluating bulk packagings larger than 2000 gallons. This project involved classifying the PIH into severity categories so that only one set of packaging performance criteria would be needed for each severity category rather than a separate set of performance criteria for each individual PIH. By grouping the PIH into Hazard Zones, Packaging Groups and performance standards for these Hazard Zones can be defined. Each Hazard Zone can correspond to a Packaging Group or, as in 49CFR173 for non-bulk packagings, one Packaging Group may cover more than one Hazard Zone. If the packaging groups are chosen to correspond to the classification categories presented in this report, then the maximum allowable leak rates used to define these categories could be used as the maximum allowable leak rates for the performance oriented packaging standards. The results discussed in this report are intended to provide quantitative guidance for the appropriate authorities to use in making these decisions.
Date: February 1, 1996
Creator: Griego, N.R. & Weiner, R.F.
Partner: UNT Libraries Government Documents Department