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IRIS Glossary /Acronyms & Abbreviations
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
- 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
- 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.
C
- 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
D
- 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
- 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
F
- 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
- g - grams
- GI - gastrointestinal
- GPT - glutamic-pyruvic transaminase
H
- 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 Database
I
- 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
K
- kg - kilogram
L
- 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
- 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.
N
- 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
O
- 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
- 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
R
- 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
S
- 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
T
- TB - tracheobronchial region of the respiratory tract
- TCC - Tagliabue closed cup, a standard method of determining flash points
- TDB - Toxicology Database
- 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
U
- UCL - upper confidence limit
- UEL - upper explosive limit
- UF - uncertainty factor
- µg - microgram
- umol - micromoles
V
- 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
W
- WBC - white blood cell(s)
- WQC - Water Quality Criteria