Glossary

ACGIH (American Conference of Governmental Industrial Hygienists). ACGIH is a member-based organization and community of professionals that advances worker health and safety through education and the development and dissemination of scientific and technical knowledge. ACGIH publishes exposure guidance values called Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs). Exposures at or below TLVs or BEIs do not create an unreasonable risk of disease or injury. TLVs and BEIs are designed for use by industrial hygienists in making decisions regarding safe levels of exposure to various chemical substances and physical agents found in the workplace.1

Acute exposure. An exposure lasting 24 hours or less.2

Acute exposure guideline levels (AEGLs). AEGLs “represent threshold exposure limits for the general public and are applicable to emergency exposures ranging from 10 min to 8 h. Three levels—AEGL-1, AEGL-2, and AEGL-3—are developed for each of five exposure periods (10 min, 30 min, 1 h, 4 h, and 8 h) and are distinguished by varying degrees of severity of toxic effects. AEGL-1 is the airborne concentration (expressed as ppm (parts per million) or mg/m3 (milligrams per cubic meter)) of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure. AEGL-2 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including susceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape. AEGL-3 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which

1

See http://www.acgih.org for more information.

2

EPA (U.S. Environmental Protection Agency). 2009. Glossary of IRIS Terms. Integrated Risk Information System, U.S. Environmental Protection Agency. [online]. Available: http://www.epa.gov/IRIS/help_gloss.htm [accessed May 5, 2009].



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 165
Glossary ACGIH (American Conference of Governmental Industrial Hygienists). ACGIH is a member-based organization and community of professionals that advances worker health and safety through education and the development and dissemination of scientific and technical knowledge. ACGIH publishes exposure guidance values called Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs). Exposures at or below TLVs or BEIs do not create an unreason- able risk of disease or injury. TLVs and BEIs are designed for use by industrial hygienists in making decisions regarding safe levels of exposure to various chemical substances and physical agents found in the workplace.1 Acute exposure. An exposure lasting 24 hours or less.2 Acute exposure guideline levels (AEGLs). AEGLs “represent threshold expo- sure limits for the general public and are applicable to emergency exposures ranging from 10 min to 8 h. Three levels—AEGL-1, AEGL-2, and AEGL-3— are developed for each of five exposure periods (10 min, 30 min, 1 h, 4 h, and 8 h) and are distinguished by varying degrees of severity of toxic effects. AEGL-1 is the airborne concentration (expressed as ppm (parts per million) or mg/m3 (milligrams per cubic meter)) of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of expo- sure. AEGL-2 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including sus- ceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape. AEGL-3 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which 1 See http://www.acgih.org for more information. 2 EPA (U.S. Environmental Protection Agency). 2009. Glossary of IRIS Terms. Inte- grated Risk Information System, U.S. Environmental Protection Agency. [online]. Avail- able: http://www.epa.gov/IRIS/help_gloss.htm [accessed May 5, 2009]. 165

OCR for page 165
166 Exposure Guidance Levels for Selected Submarine Contaminants it is predicted that the general population, including susceptible individuals, could experience life-threatening health effects or death.”3 AEGL. See acute exposure guideline levels. Aerosol. “A suspension of liquid or solid particles in a gas.”4 Alveolar macrophage. “One of the rounded, granular, mononuclear phagocytes within the alveoli of the lungs that ingest inhaled particulate matter.”5 ATSDR (Agency for Toxic Substances and Disease Registry). The ATSDR is an agency of the Department of Health and Human Services that was created by Congress under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), commonly known as the Superfund Act. Its mission is to serve the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harm- ful exposures and disease related to toxic substances. ATSDR defines minimal risk levels (MRLs) for hazardous substances.6 CAMS. See central atmosphere monitoring system. CEGL. See continuous exposure guidance level. Ceiling concentration. A concentration that shall not be exceeded during any part of a working day.7 Central atmosphere monitoring system (CAMS). CAMS monitors the subma- rine atmosphere by using an infrared spectrometer to measure carbon monoxide and a fixed-collector mass spectrometer to measure oxygen, nitrogen, carbon dioxide, hydrogen, water vapor, and fluorocarbons 11, 12, and 114.8 Chronic exposure. A repeated exposure lasting more than approximately 10% 3 NRC (National Research Council). 2001. Standing Operating Procedures for Devel- oping Acute Exposure Guideline Levels for Hazardous Chemicals. Washington, DC: National Academy Press. 4 Hawley, G.G. 1981. The Condensed Chemical Dictionary, 10th Ed. New York: Van Nostrand Reinhold Company. 5 Dorland, N. 1988. Dorland’s Illustrated Medical Dictionary, 28th ed. Philadelphia, MD: W.B. Saunders Company. 6 See http://www.atsdr.cdc.gov/ for more information. 7 29 CFR 1910.1000(a)(1) [online]. Available: http://www.osha.gov/pls/oshaweb/ owadisp.show_document?p_id=9991&p_table=STANDARDS [accessed May 5, 2009]. 8 NRC (National Research Council). 1988. Submarine Air Quality. Washington, DC: National Academy Press.

OCR for page 165
167 Appendix A of the lifespan in humans or approximately 90 days to 2 years in laboratory ani- mals.2 Continuous exposure guidance level (CEGL). A CEGL is defined as a ceiling concentration designed to prevent any immediate or delayed adverse health ef- fect or degradation in crew performance resulting from a continuous exposure lasting up to 90 days.9 EEGL. See emergency exposure guidance level. Electrostatic precipitator. A system to clear particles and aerosols from air.8 Emergency exposure guidance level (EEGL). An EEGL is defined as a ceiling concentration that will not cause irreversible harm or prevent performance of essential tasks, such as closing a hatch or using a fire extinguisher, during a rare emergency situation usually lasting 1-24 hours.9 EPA (U.S. Environmental Protection Agency). “The mission of [EPA] is to protect human health and the environment.” The agency is responsible for de- veloping and enforcing pertinent environmental regulations, providing grants, studying environmental issues, sponsoring partnerships, and teaching the public about the environment.10 Forced expiratory volume at 1 second (FEV1). FEV1 is a standard test of lung function. It is the “volume of air that can be forcibly exhaled during the first second of expiration following a maximal inspiration.”2 Forced vital capacity (FVC). FVC is a standard test of lung function. It is “the maximal volume of air that can be exhaled as forcibly and rapidly as possible after a maximal inspiration.”2 Fumes. “The particulate, smoke-like emanation from the surface of heated met- als. Also, the vapor evolved from concentrated acids (sulfuric, nitric); from evaporating solvents; or as a result of combustion or other decomposition reac- tions (exhaust fume).”4 FVC. See forced vital capacity. Gas. One of the three states of matter, “characterized by very low density and 9 NRC (National Research Council). 1986. Criteria and Methods for Preparing Emer- gency Exposure Guidance Level (EEGL), Short-Term Public Emergency Guidance Level (SPEGL), and Continuous Exposure Guidance Level (CEGL) Documents. Washington, DC: National Academy Press. 10 See http://www.epa.gov/ for more information.

OCR for page 165
168 Exposure Guidance Levels for Selected Submarine Contaminants viscosity (relative to liquids and solids); comparatively great expansion and con- traction with changes in pressure and temperature; ability to diffuse readily into other gases; and ability to occupy with almost complete uniformity the whole of any container.”4 IARC (International Agency for Research on Cancer). IARC is an agency of the World Health Organization. IARC’s carcinogenicity classifications are as follows:11 Group 1. “The agent is carcinogenic to humans. This category is used when there is sufficient evidence of carcinogenicity in humans.” Group 2A. “The agent is probably carcinogenic to humans. This category is used when there is limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals.” Group 2B. “The agent is possibly carcinogenic to humans. This category is used for agents for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimen- tal animals.” Group 3. “The agent is not classifiable as to its carcinogenicity in humans. This category is used most commonly for agents for which the evidence of carcinogenicity is inadequate in humans and inadequate or limited in ex- perimental animals.” Group 4. “The agent is probably not carcinogenic to humans. This cate- gory is used for agents for which there is evidence suggesting lack of car- cinogenicity in humans and in experimental animals” Irritant. A toxicant that exerts deleterious effects by causing inflammation of tissues on contact. Irritants can act on the respiratory system and cause pulmo- nary edema at high concentrations. At low concentrations, most effects are re- versible with cessation of exposure.12 Irreversible harm. Permanent damage or injury to health. Emergency exposure guidance levels (EEGLs) are designed to avoid or prevent irreversible harm.9 LC01. Statistical determination of the lethal concentration for 1% of the sample population.12 LC50. Statistical determination of the lethal concentration for 50% of the sample population.12 11 IARC (International Agency for Research on Cancer). 2006. Preamble to the IARC Monographs on the Evaluation of Carcinogenic Risk to Humans [online]. Available: http://monographs.iarc.fr/ENG/Preamble/index.php [accessed July 8, 2009]. 12 Hodgson, E., R.B. Mailman, and J.E. Chambers, eds. 1988. Dictionary of Toxicol- ogy. New York: Van Nostrand Reinhold Company.

OCR for page 165
169 Appendix A LOAEL. See lowest observed-adverse-effect level. Lowest observed-adverse-effect level (LOAEL). A LOAEL is the “lowest exposure level at which there are [statistically or] biologically significant in- creases in frequency or severity of adverse effects between the exposed popula- tion and its appropriate control group.”2 Minimal risk level (MRL). ATSDR’s “estimate of daily human exposure to a hazardous substance at or below which that substance is unlikely to pose a measurable risk of harmful (adverse), noncancerous effects. MRLs are calcu- lated for a route of exposure (inhalation or oral) over a specified time period (acute, intermediate, or chronic).”13 MRL. See minimal risk level. NIOSH (National Institute for Occupational Safety and Health). The Occu- pational Safety and Health Act of 1970 created NIOSH and the Occupational Safety and Health Administration (OSHA). NIOSH is the “federal agency re- sponsible for conducting research and making recommendations for the preven- tion of work-related injury and illness.” It is part of the Centers for Disease Con- trol and Prevention and the Department of Health and Human Services.14 NOAEL. See no-observed-adverse-effect level. NOEL. See no-observed-effect level. No-observed-adverse-effect level (NOAEL). A NOAEL is “the highest expo- sure level at which there are no [statistically or] biologically significant in- creases in the frequency or severity of adverse effects between the exposed population and its appropriate control; some effects may be produced at this level, but they are not considered as adverse or precursors of adverse effects.”2 No-observed-effect level (NOEL). “An exposure level at which there are no statistically or biologically significant increases in the frequency or severity of any effect between the exposed population and its appropriate control.”2 OSHA (Occupational Safety and Health Administration). OSHA is an agency of the U.S. Department of Labor. It is authorized to set workplace health and safety standards for a wide variety of physical and chemical hazards and occupational situations. OSHA establishes permissible exposure limits (PELs) 13 ATSDR (Agency for Toxic Substances and Disease Registry). 2003. ATSDR Glos- sary of Terms [online]. Available: http://www.atsdr.cdc.gov/glossary.html [accessed May 5, 2009]. 14 See http://www.cdc.gov/niosh/about.html for more information.

OCR for page 165
170 Exposure Guidance Levels for Selected Submarine Contaminants for a typical 8-hour workday within a 40-hour workweek and short-term expo- sure limits (STELs) applicable to a 15-min period within a workday.15 PEL. See permissible exposure limit. PEL-TWA. See permissible exposure limit. Permissible exposure limit (PEL). A PEL is a regulatory limit on the amount or concentration of a substance to which a worker may be exposed.16 The per- missible exposure limit–time-weighted average (PEL-TWA) “must not be ex- ceeded during any 8-hour workshift of a 40-hour workweek.”17 RD50. A statistically estimated concentration resulting in 50% reduction in respi- ratory rate.18 Recommended exposure limit (REL). For NIOSH, a REL is “a time-weighted average concentration [TWA] for up to a 10-hour workday during a 40-hour workweek… ceiling REL should not be exceeded at anytime.”17 Reference concentration (RfC). “An estimate…of a continuous inhalation ex- posure to the human population…that is likely to be without an appreciable risk of deleterious effects during a lifetime. It can be derived from a NOAEL, LOAEL, or a benchmark concentration, with uncertainty factors generally ap- plied to reflect limitations of the data used. Generally used in EPA’s non-cancer health assessments.”2 REL. See recommended exposure limit. Relative risk. The “ratio of the risk of a disease or death among the exposed to that among the unexposed” or the “ratio of the cumulative incidence rate in the exposed to the cumulative incidence rate in the unexposed.”19 15 See http://www.osha.gov/ for more information. 16 OSHA (Occupational Safety and Health Administration). 2006. Permissible Expo- sure Limits (PELs) [online]. Available: http://www.osha.gov/SLTC/pel/ [accessed May 5, 2009]. 17 NIOSH (National Institute for Occupational Safety and Health). 2005. NIOSH Pocket Guide to Chemical Hazards. [online]. Available: http://www.cdc.gov/niosh/npg/ pgintrod.html [accessed May 5, 2009]. 18 Kuwabara, Y., G. Alexeeff, R. Broadwin, and A. Salmon. 2007. Evaluation and ap- plication of the RD50 for determining acceptable exposure levels of airborne sensory irri- tants for the general public. Environ. Health Perspect. 115(11):1609-1616. 19 IUPAC (International Union of Pure and Applied Chemistry). 1993. Glossary for Chemists of Terms Used in Toxicology. [online]. Available: http://www.sis.nlm.nih.gov/ enviro/glossarymain.html [accessed May 5, 2009].

OCR for page 165
171 Appendix A Reversible effect. An injury from which a target tissue or organ can recover or regenerate.20 RfC. See reference concentration. SEAL. See submarine escape action levels. Sensory Irritation. Stimulation of trigeminal nerves causing sensations of tick- ling, itching, or pain in the nose of humans and changes in specific breathing patterns in rodents that consist of a pause at the onset of each expiration.21 Short-term exposure limit (STEL). “A 15-minute TWA exposure that should not be exceeded at any time during a workday.”17 Short-term public emergency guidance levels (SPEGLs). ”A suitable concen- tration for unpredicted, single, short-term, emergency exposures, of the general public.”9 SMAC. See spacecraft maximum allowable concentrations. Spacecraft maximum allowable concentrations (SMACs). “Short-term SMACs refer to concentrations of airborne substances (such as gas, vapor, or aerosol) that will not compromise the performance of specific tasks during emergency conditions lasting up to 24 hr. Exposure to 1- or 24-hr SMACs will not cause serious or permanent effects but may cause reversible effects that do not impair judgment or interfere with proper responses to emergencies such as fires or accidental releases. Long-term SMACs are intended to avoid adverse health effects (either immediate or delayed) and to avoid degradation in crew performance with continuous exposure in a closed space-station environment for as long as 180 days.” SMACs were developed for astronauts (healthy individu- als)22 SMR. See standardized mortality ratio. SPEGL. See short-term public emergency guidance levels. Standardized mortality ratio (SMR). SMR is a measure of population health. 20 Stedman, L.S. 1982. Stedman’s Medical Dictionary, 24th Ed. Baltimore, MD: Wil- liams and Wilkins. 21 Alarie, Y. 1973. Sensory irritation of the upper airways by airborne chemicals. Toxi- col. Appl. Pharmacol. 24(2): 279-297. 22 NRC (National Research Council). 1994. Spacecraft Maximum Allowable Concen- trations for Selected Airborne Contaminants, Vol.1. Washington, DC: National Academy Press.

OCR for page 165
172 Exposure Guidance Levels for Selected Submarine Contaminants It is “the relative measure of the difference in risk between the exposed and un- exposed populations in a cohort study. . .This measure is usually standardized to control for any differences in age, sex, and/or race between the exposed and reference populations.”2 STEL. See short-term exposure limit. Subchronic exposure. Repeated exposures over an intermediate period of time (about 1 to 3 months).12 Submarine escape action levels (SEALs). “SEAL 1 is defined as the maximum concentration of a gas in a disabled submarine below which healthy submariners can be exposed for up to 10 days without experiencing reversible health effects. SEAL 2 is defined as the maximum concentration of a gas in a disabled subma- rine below which healthy submariners can be exposed for up to 24 hours without experiencing irreversible heath effects.”23 Threshold Limit Value (TLV). A TLV is the “recommended guidelines for occupational exposure to airborne contaminants published by the American Conference of Governmental Industrial Hygienists (ACGIH). TLVs represent the average concentration in mg/m3 for an 8-hour work day and a 40-hour work week to which nearly all workers may be repeatedly exposed, day after day, without adverse reaction.”2 Time-weighted average (TWA). A TWA is the average concentration of a regulated chemical to which a worker may be repeatedly exposed during a con- ventional 8-hour workday and a 40-hour workweek without adverse effect.17 TLV. See Threshold Limit Value. TWA. See time-weighted average. UF. See uncertainty factor. Uncertainty factor (UF). A UF (for example, 1, 2, 3, or 10) can be used when deriving human health risk reference values from experimental data to account for inter- or intraspecies differences, database gaps, extrapolations from high to low dose, or other adjustments required. Multiple UFs can be used in a calcula- tion. A UF of 10 is considered to be a health-protective default value to be em- ployed when little is known about a particular source of variability or uncer- tainty, such as intraspecies differences or lack of information on a relevant 23 NRC (National Research Council). 2002. Review of Submarine Escape Action Levels for Selected Chemicals. Washington, DC: National Academy Press.

OCR for page 165
173 Appendix A health effect. As additional research becomes available, UFs change as indicated by the new information.2 Vent fog precipitator. A system used in the submarine engine room to clear the air of oil mists.8 Volatile organic compounds. Volatile organic compounds are “organic com- pounds that evaporate readily into the air. [They] include substances such as benzene, toluene, methylene chloride, and methyl chloroform.”13

OCR for page 165