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Acronyms and Abbreviations

January 27, 1993

  • (+/-) - plus or minus, as in defining the precision of a number

  • AADI - Adjusted Acceptable Daily Intake

  • AChE - acetylcholinesterase

  • ACGIH - American Conference of Governmental Industrial Hygienists

  • ADI - Acceptable Daily Intake

  • AHFS - American Hospital Formulary Service

  • a.i. - active ingredient

  • AIHA - American Industrial Health Association

  • AMA - American Medical Association

  • AOAC - Association of Official Analytical Chemists

  • APA - American Pharmaceutical Association

  • ASCII - American Standard Code for Information Exchange

  • ASHP - American Society of Hospital Pharmacists

  • AUR - Air Unit Risk

  • b:a lambda(a) - Blood-to-air partition coefficient of the chemical for the experimental animal species used in the HEC derivation of an RfC

  • b:a lambda(h) - Blood-to-air partition coefficient of the chemical for the human used in the HEC derivation of an RfC

  • BHP - biodegradation, hydrolysis, and photolysis

  • BOD5 - biochemical oxygen demand as measured in the standard 5-day test

  • BUN - blood urea nitrogen

  • Bw - body weight

  • BWa - Body weight (kg) for experimental animal species used in the HEC derivation of an RfC.

  • BWh - Body weight (kg) for human used in the HEC derivation of an RfC.

  • CAG - Carcinogen Assessment Group, U.S. EPA

  • CAS - Chemical Abstracts Service

  • CBI - Confidential business information

  • cc - cubic centimeters

  • CC - closed cup

  • CDC - Centers for Disease Control

  • CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act of 1980

  • CFR - Code of Federal Regulations

  • CF - Conversion factor based on PBPK modeling used in the HEC derivation of an RfC for gases. Note: The CF is specific for the experimental animal species and the exposure regimen and concentration simulated.

  • ChE - cholinesterase

  • CHO - Chinese hamster ovary

  • CIIT - Chemical Industry Institute of Toxicology

  • CNS - central nervous system

  • CPK - creatine phosphokinase

  • CRAVE - Carcinogen Risk Assessment Verification Endeavor

  • cu.m - cubic meter

  • CWA - Clean Water Act

  • DASE - Dutch Association of Safety Experts

  • DHEW - U.S. Department of Health, Education, and Welfare (now U.S. Department of Health and Human Services)

  • DNA - deoxyribonucleic acid

  • DOT - U.S. Department of Transportation

  • DW - drinking water

  • DWEL - Drinking Water Equivalent Level

  • E - exponent (e.g., 1.5E-6 = 1.5 x 10 to the power of -6)

  • EED - estimated exposure dose

  • EEG - electroencephalogram

  • EKG - electrocardiogram

  • ELISA - enzyme-linked immunosorbent assay

  • EMTD - estimated maximum tolerated dose

  • EP - Extraction Procedure

  • ER - Extrarespiratory. Refers to effects peripheral to the respiratory system as the portal-of-entry, or systemic effects.

  • ET - Extrathoracic region of the respiratory tract

  • EPA - U.S. Environmental Protection Agency

  • FEL - frank-effect level

  • FIFRA - Federal Insecticide, Fungicide, and Rodenticide Act

  • FOI - Freedom of Information

  • F1 - first filial generation (in experimental animals)

  • FR - Federal Register

  • FRC - functional reserve capacity

  • FTS - Federal Telecommunications System

  • FWS - U.S. Fish and Wildlife Service

  • g - grams

  • GI - gastrointestinal

  • GPT - glutamic-pyruvic transaminase

  • HA - Health Advisory

  • HAPPS - Hazardous Air Pollution Prioritization System

  • HAS - Health Assessment Summary

  • HCT - hematocrit

  • HDT - highest dose tested

  • HEC - human equivalent concentration

  • HEEP - Health and Environmental Effects Profile

  • Hgb - hemoglobin

  • HHS - U.S. Department of Health and Human Services

  • HSDB - Hazardous Substance Data Base

  • IARC - International Agency for Research on Cancer

  • ICR - Institute of Cancer Research

  • ICRP - International Commission for Radiological Protection

  • i.m. - intramuscular

  • i.p. - intraperitoneal

  • i.v. - intravenous

  • IRIS - Integrated Risk Information System

  • ITII - International Technical Information Institute

  • kg - kilogram

  • L - liter

  • LCLO - Lethal Concentration Low; the lowest concentration at which death occurred

  • LC50 - Lethal Concentration 50; concentration lethal to 50% of the animals LDLO

  • LD50 - Lethal Dose 50; dose lethal to 50% of the animals

  • LDH - lactic-acid dehydrogenase

  • LDT - lowest dose tested

  • LEL - lower explosive limit

  • LEL - lowest-effect level

  • Lethal Dose Low - the lowest dose at which death occurred

  • LOAEL - lowest-observed-adverse-effect level

  • LOAEL(ADJ) - LOAEL adjusted to continuous exposure duration from an intermittent regimen by hour/day and days/7 days.

  • LOAEL(HEC) - LOAEL adjusted for dosimetric differences across species to a human equivalent concentration.

  • m - meter

  • MCL - maximum contaminant level

  • MCLG - maximum contaminant level goal

  • MED - minimum effective dose

  • MEFV - maximum expiratory flow volume

  • MF - modifying factor

  • mg - milligram

  • mg/kg - milligrams per kilogram

  • mg/L - milligrams per liter

  • mmHg - millimeters of mercury; a measure of pressure

  • MMAD - mass median aerodynamic diameter

  • MOE - margin of exposure

  • MOS - margin of safety

  • MTD - maximum tolerated dose

  • MTL - median threshold limit

  • MVa - Minute ventilatory volume for experimental animal species (composite value expressed in cu.m/day) used in the HEC derivation of an RfC.

  • MVh - Minute ventilatory volume for human (composite value expressed in cu.m/day) used in the HEC derivation of an RfC.

  • MVho - Minute ventilatory volume for human in an occupational environment, assuming 8 hour/day exposure (composite value expressed in cu.m/day), used in the HEC derivation of an RfC.

  • NAAQS - National Ambient Air Quality Standards

  • NAS - National Academy of Sciences

  • NESHAP - National Emission Standards for Hazardous Air Pollutants

  • NFPA - National Fire Prevention Association

  • ng - nanogram

  • NIH - National Institutes of Health

  • NIOSH - National Institute for Occupational Safety and Health

  • NLM - National Library of Medicine

  • NOAEL - no-observed-adverse-effect level

  • NOAEL(ADJ) - NOAEL adjusted to continuous exposure duration from an intermittent regimen by hour/day and days/7 days.

  • NOAEL(HEC) - NOAEL adjusted for dosimetric differences across species to a human equivalent concentration.

  • NOEL - no-observed-effect level

  • n.a. - not available

  • n.o.s. - not otherwise specified

  • NRC - National Research Council

  • NSPS - New Source Performance Standards

  • NTIS - National Technical Information Service

  • NTP - National Toxicology Program

  • OAQPS - Office of Air Quality Planning and Standards, U.S. EPA

  • OAR - Office of Air and Radiation, U.S. EPA

  • OARM - Office of Administration and Resources Management, U.S. EPA

  • OC - open cup

  • OW - Office of Water, U.S. EPA

  • OHEA - Office of Health and Environmental Assessment, U.S. EPA

  • OHM/TADS - Oil and Hazardous Materials Technical Assistance Data Systems

  • OPP - Office of Pesticide Programs, U.S. EPA

  • OPPE - Office of Policy Planning and Evaluation, U.S. EPA

  • OPTS - Office of Pesticides and Toxic Substances, U.S. EPA

  • ORD - Office of Research and Development, U.S. EPA

  • OSHA - U.S. Occupational Safety and Health Administration

  • OST - Office of Science and Technology, U.S. EPA

  • OSWER - Office of Solid Waste and Emergency Response, U.S. EPA

  • OTS - Office of Toxic Substances, U.S. EPA

  • OWRS - Office of Water Regulations and Standards, U.S. EPA

  • P - probit dose extrapolation model

  • PBPK - physiologically based pharmacokinetic

  • pCi - picocurie

  • PD - Position Document

  • PEL - permissible exposure limit

  • PHS - U.S. Public Health Service

  • p.o. - per os (by mouth)

  • ppb - parts per billion

  • ppm - parts per million

  • PU - pulmonary region of the respiratory tract

  • RA - risk assessment

  • RBC - red blood cell(s)

  • RCRA - Resource Conservation and Recovery Act

  • RDDR - Regional deposited dose ratio used in derivation of an HEC for particles.

  • RDDR(ER) - Regional deposited dose ratio used in the HEC derivation of an RfC for an observed extrarespiratory effect of particles.

  • RDDR(ET) - Regional deposited dose ratio used in the HEC derivation of an RfC for an observed effect of particles in the extrathoracic region of the respiratory tract.

  • RDDR(PU) - Regional deposited dose ratio used in the HEC derivation of an RfC for an observed effect of particles in the pulmonary region of the respiratory tract.

  • RDDR(TB) - Regional deposited dose ratio used in the HEC derivation of an RfC for an observed effect of particles in the tracheobronchial region of the respiratory tract.

  • RDDR(TH) - Regional deposited dose ratio used in the HEC derivation of an RfC for an observed effect of particles in the thoracic region of the respiratory tract.

  • RDDR(TOTAL) - Regional deposited dose ratio used the HEC derivation of an RfC for an observed effect of particles in the total respiratory tract.

  • RGDR - Regional gas dose ratio used in derivation of an HEC for gases.

  • RGDR(ET) - Regional gas dose ratio used in the HEC derivation of an RfC for an observed effect of a gas in the extrathoracic region of the respiratory tract.

  • RGDR(PU) - Regional gas dose ratio used in the HEC derivation of an RfC for an observed effect of a gas in the pulmonary region of the respiratory tract.

  • RGDR(TB) - Regional gas dose ratio used in the HEC derivation of an RfC for an observed effect of a gas in the tracheobronchial region of the respiratory tract.

  • RGDR(TH) - Regional gas dose ratio used in the HEC derivation of an RfC for an observed effect of a gas in the thoracic region of the respiratory tract.

  • RGDR(TOTAL) - Regional gas dose ratio used in the HEC derivation of an RfC for an observed effect of a gas in the total respiratory tract.

  • RfD - Oral Reference Dose

  • RfC - Inhalation Reference Concentration

  • RgD - Regulatory Dose

  • RM - risk management

  • RPAR - rebuttable presumption against registration

  • RQ - Reportable Quantity

  • RTECS - Registry of Toxic Effects of Chemical Substances

  • RV - residual volume

  • Sa - Surface area (in sq.cm) for respiratory tract region for experimental animal species used in the HEC derivation of an RfC.

  • Sa(ET) - Surface area (in sq.cm) of extrathoracic region for experimental animal species used in the HEC derivation of an RfC.

  • Sa(TB) - Surface area (in sq.cm) of tracheobronchial region for experimental animal species used in the HEC derivation of an RfC.

  • Sa(TH) - Surface area (in sq.cm) of thoracic region for experimental animal species used in the HEC derivation of an RfC.

  • Sa(PU) - Surface area (in sq.cm) of pulmonary region for experimental animal species used in the HEC derivation of an RfC.

  • Sa(TOTAL) - Surface area (in sq.cm) of total respiratory system for experimental animal species used in the HEC derivation of an RfC.

  • SAB - Science Advisory Board

  • SANSS - Structure and Nomenclature Search System

  • SAP - serum alkaline phosphatase

  • SARA - Superfund Amendments and Reauthorization Act of 1986 s.c. subcutaneous

  • SCE - sister-chromatid exchange

  • SDWA - Safe Drinking Water Act

  • SF - safety factor

  • SGOT - serum glutamic-oxaloacetic transaminase

  • SGPT - serum glutamic-pyruvic transaminase

  • Sh - Surface area (in sq.cm) of respiratory tract for human used in the HEC derivation of an RfC.

  • Sh(ET) - Surface area (in sq.cm) of extrathoracic region for human used in the HEC derivation of an RfC.

  • Sh(TB) - Surface area (in sq.cm) of tracheobronchial region for human used in the HEC derivation of an RfC.

  • Sh(TH) - Surface area (in sq.cm) of thoracic region for human used in the HEC derivation of an RfC.

  • Sh(PU) - Surface area (in sq.cm) of pulmonary region for human used in the HEC derivation of an RfC.

  • Sh(TOTAL) - Surface area (in sq.cm) of total respiratory system for human used in the HEC derivation of an RfC.

  • sigma g - geometric standard deviation

  • SMCL - secondary maximum contaminant level

  • SMR - standard mortality ratio

  • sq.cm. - square centimeters

  • SRI - Stanford Research Institute

  • STEL - short-term exposure limit

  • TB - tracheobronchial region of the respiratory tract

  • TCC - Tagliabue closed cup, a standard method of determining flash points

  • TDB - Toxicology Data Base

  • TH - thoracic (TB + PU) region of the respiratory tract

  • TLV - Threshold Limit Value

  • TOC - Tagliabue open cup, a standard method of determining flash points

  • TOTAL - total respiratory tract

  • TSCA - Toxic Substances Control Act

  • TWA - time-weighted averageý

  • UCL - upper confidence limit

  • UEL - upper explosive limit

  • UF - uncertainty factor

  • ug - microgram

  • umol - micromoles

  • VAa - Alveolar ventilation rate (cu.m/day) for experimental animal species used in HEC derivation of an RfC.

  • VAh - Alveolar ventilation rate (cu.m/day) for human used in HEC derivation of an RfC.

  • VOC - volatile organic compound

  • v/v - volume for volume

  • WBC - white blood cell(s)

  • WQC - Water Quality Criteria


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Last updated: 20 February 1998
URL: http:/www.epa.gov/iris/GLOSSARY.HTM