This article possibly contains original research. (February 2010) |
Many gases have toxic properties, which are often assessed using the LC50 (median lethal concentration) measure. In the United States, many of these gases have been assigned an NFPA 704 health rating of 4 (may be fatal) or 3 (may cause serious or permanent injury), and/or exposure limits (TLV, TWA/PEL, STEL, or REL) determined by the ACGIH professional association. Some, but by no means all, toxic gases are detectable by odor, which can serve as a warning. Among the best known toxic gases are carbon monoxide, chlorine, nitrogen dioxide and phosgene.
Definitions
edit- Toxic: a chemical that has a median lethal concentration (LC50) in air of more than 200 parts per million (ppm) but not more than 2,000 parts per million by volume of gas or vapor, or more than 2 milligrams per liter but not more than 20 milligrams per liter of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 300 grams each.[1][2]
- Highly Toxic: a gas that has a LC50 in air of 200 ppm or less.[2]
- NFPA 704: Materials that, under emergency conditions, can cause serious or permanent injury are given a Health Hazard rating of 3. Their acute inhalation toxicity corresponds to those vapors or gases having LC50 values greater than 1,000 ppm but less than or equal to 3,000 ppm. Materials that, under emergency conditions, can be lethal are given a Health Hazard rating of 4. Their acute inhalation toxicity corresponds to those vapors or gases having LC50 values less than or equal to 1,000 ppm.
List
edit| Chemical name[3] | Chemical formula |
CAS number | NIOSH IDLH (ppm) |
OSHA PEL / NIOSH REL / ACGIH TLV[4] | NFPA 704 Ratings | LC50 (ppm)[5] | Odor threshold (ppm)[5] | |
|---|---|---|---|---|---|---|---|---|
| Health | Special Hazard | |||||||
| Arsenic pentafluoride | AsF5 | 7784-36-3 | 5 | NIOSH PEL TWA 0.001 ppm; REL Ceiling 0.0002 ppm (15 min) |
4 | |||
| Arsine[4] | AsH3 | 7784-42-1 | 3 | NIOSH REL (C) (15 min): 0.002 mg/m3; OSHA PEL: 0.05 ppm; ACGIH (2006) TWA-TLV 0.05 ppm |
4 | 120 (rat, 10 min) | ||
| Bis(trifluoromethyl)peroxide | C2F6O2 | 927-84-4 | 10 | |||||
| Boron tribromide[6] | BBr3 | 10294-33-4 | 50 | ACGIH (1990) / PEL Ceiling limit 1 ppm; AEGL-1: 0.33 ppm, AEGL-2: 1.7 ppm, AEGL-3: 5 ppm |
3 | |||
| Boron trichloride[7] | BCl3 | 10294-34-5 | 25 | No exposure limits have established; 2500 (TQ) |
4 | 2541 (rat, 1 h)[8] | ||
| Boron trifluoride | BF3 | 7637-07-2 | 25 | OSHA, ACGIH (1962) 1 ppm ceiling | 4 | 436 (4 h)[8] | ||
| Bromine | Br2 | 7726-95-6 | 3 | OSHA PEL 8-hr TWA: 0.1 ppm; ACGIH (1991) STEL-TLV 0.3 ppm |
3 | OX | 174 (mice) | <0.01 |
| Bromine chloride | BrCl | 13863-41-7 | 1500 (TQ) | 3 | OX | |||
| Bromomethane | CH3Br | 74-83-9 | 250 | NIOSH PEL 20 ppm | 3 | 302 (Rat, 8 h)[9] | ||
| Carbon monoxide | CO | 630-08-0 | 1,200 (moderately toxic) |
ACGIH (1989) TWA TLV 25 ppm; NIOSH 35 ppm; NIOSH 200 ppm Ceiling limit |
3 | 4600/5000[10] | ||
| Chlorine | Cl2 | 7782-50-5 | 10 | ACGIH (1986) STEL-TLV 1 ppm | 3 | OX | 433 (10 min), 250 (30 min) |
1 |
| Chlorine pentafluoride | ClF5 | 13637-63-3 | AEGL-2: 0.33 ppm, AEGL-3: 2.7 ppm |
194 (Rat) | ||||
| Chlorine trifluoride | ClF3 | 7790-91-2 | 12 | ACGIH (1979) Ceiling limit 0.1 ppm | 4 | 95 (Rat, 4 h) | Inadequate odor | |
| Chloropicrin[note 1] | CCl3NO2 | 76-06-2 | 2 | ACGIH (1990) TWA-TLV 0.1 ppm | 4 | 9.7 (Mouse, 4 h) | ||
| Cyanogen | C2N2 | 460-19-5 | ACGIH (1966) TWA-TLV 10 ppm | 4 | ||||
| Cyanogen chloride | CNCl | 506-77-4 | ACGIH (1977) ceiling limit 0.3 ppm | 4 | ||||
| Diazomethane | CH2N2 | 334-88-3 | 2 | ACGIH (1970) TWA-TLV 0.2 ppm | 4 | 175 (Cat, 10 min) | ||
| Diborane | B2H6 | 19287-45-7 | 15 | ACGIH (1990) TWA-TLV 0.1 ppm | 4 | 40 (Rat, 4 h) | Inadequate odor | |
| Dichloroacetylene[note 2] | C2Cl2 | 7572-29-4 | NIOSH REL 0.1 ppm Ceiling | |||||
| Dichlorosilane | H2Cl2Si | 4109-96-0 | 2500 (TQ) | 4 | 1785-2092 | |||
| Dimethylmercury | HgC2H6 | 593-74-8 | 4 | |||||
| Ethylene oxide (anhydrous) | C2H4O | 75-21-8 | 800 | REL TWA <0.1 ppm, 5 ppm Ceiling | 3 | 90 mg/L (fish, 24 h) | ||
| Fluorine | F2 | 7782-41-4 | ACGIH (1970) STEL-TLV 2 ppm | 4 | OX | 20 ppb | ||
| Formaldehyde (anhydrous) | CH2O | 50-00-0 | 20 | NIOSH REL 0.016 ppm, Ceiling limit 0.1 ppm | 3 | 333 (mouse, 2 h) | ||
| Germane | GeH4 | 7782-65-2 | NIOSH REL 0.2 ppm | 4 | 440 (mice 2 h) | |||
| Hydrogen azide | HN3 | 7782-79-8 | NIOSH REL: 0.1 ppm Ceiling | 4 | ||||
| Hydrogen cyanide | HCN | 74-90-8 | 50 | PEL TWA 10 ppm; REL ST 4.7 ppm |
4 | 503 (Rat, 5 min) | ||
| Hydrogen fluoride | HF | 7664-39-3 | 30 | PEL TWA 3 ppm; REL TWA 3 ppm (2.5 mg/m³); TWA 3 ppm |
4 | POI | LCLo 313 (rabbit, 7 hr) | |
| Hydrogen selenide | H2Se | 7783-07-5 | 1 | ACGIH (1990) TWA-TLV 0.05 ppm | 4 | 1.8 (G.Pig, 47 h) | ||
| Hydrogen sulfide | H2S | 7783-06-4 | 100 | NIOSH PEL: Ceiling 20 ppm; REL Ceiling 10 ppm; ACGIH (1990) STEL-TLV 15 ppm |
4 | 444 | 0.3 | |
| Hydrogen telluride | H2Te | 7783-09-7 | 4 | |||||
| Nickel tetracarbonyl | Ni(CO)4 | 13463-39-3 | 2 | NIOSH TWA PEL 0.001 ppm; ACGIH (1980) TWA-TLV 0.05 ppm |
4 | 9.642[11] | ||
| Nitrogen dioxide | NO2 | 10102-44-0 | 13 | NIOSH PEL Ceiling 5 ppm; REL ST 1 ppm |
3 | OX | 99 (mice, 1 h) | 4 |
| Osmium tetroxide | OsO4 | 20816-12-0 | 0.001 | NIOSH PEL TWA 0.0002 ppm; REL TWA 0.0002 ppm, ST 0.0006 ppm |
3 | OX | 40 (rat, 4 h) | 0.0019 |
| Oxygen difluoride | OF2 | 7783-41-7 | 0.5 | NIOSH PEL TWA 0.05 ppm; REL Ceiling 0.05 ppm; ACGIH (1983) ceiling limit 0.05 ppm |
4 | OX | 26.067 (Rhesus monkeys, 1 h) | 0.5 |
| Perchloryl fluoride | ClFO3 | 7616-94-6 | 100 | NIOSH PEL TWA 3 ppm; REL TWA 3 ppm, ST 6 ppm; ACGIH (1962) STEL-TLV 6 ppm |
3 | OX | 385 (Rat, 4 h) | |
| Perfluoroisobutylene | C4F8 | 382-21-8 | 1.2 ppm | 17 (Rat, 10 min) | ||||
| Phosgene | CCl2O | 75-44-5 | 2 | NIOSH PEL TWA 0.1 ppm; REL TWA 0.1 ppm, Ceiling 0.2 ppm; ACGIH (1992) TWA-TLV 0.1 ppm |
4 | 0.5 to 1.5 | ||
| Phosphine | PH3 | 7803-51-2 | 50 | NIOSH 0.3 ppm time weighted average; ACGIH (1992) STEL-TLV 1 ppm |
4 | 0.44 (Rat, 4 h) | ||
| Phosphorus pentafluoride[12] | PF5 | 7647-19-0 | 25 | TLV - TWA 0.25 ppm ACGIH & OSHA | 4 | |||
| Selenium hexafluoride | SeF6 | 7783-79-1 | 2 | OSHA PEL, NIOSH REL, ACGIH (1992) TWA-TLV 0.05 ppm | 3 | |||
| Silicon tetrachloride[13] | SiCl4 | 10026-04-7 | OSHA PEL, NIOSH REL 5 ppm; ACGIH TLV 2 ppm |
3 | 8000 (Rat, 4 h) | 1 - 5 | ||
| Silicon tetrafluoride | SiF4 | 7783-61-1 | 3 | 922 (Rat, 1 h) | ||||
| Stibine[14] | H3Sb | 7803-52-3 | 5 | OSHA PEL/NIOSH REL/ACGIH TLV: 0.1 ppm | 4 | |||
| Disulfur decafluoride | S2F10 | 5714-22-7 | 1 | ACGIH (1962) ceiling limit 0.01 ppm | 4 | OX | 2 (Rat, 10 min) | |
| Sulfur tetrafluoride | SF4 | 7783-60-0 | OSHA PEL/NIOSH REL/ACGIH (1992) ceiling limit 0.1 ppm[15] | 3 | 40 (Rat, 1 h)[15] | |||
| Tellurium hexafluoride | TeF6 | 7783-80-4 | 1 | NIOSH REL/ACGIH (1992) TWA-TLV 0.02 ppm | ||||
| Tetraethyl pyrophosphate[note 1] | C8H20O7P2 | 107-49-3 | 5 | ACGIH (2006) TWA-TLV 0.01 mg/m3 | 4 | |||
| Sulfotep | C8H20O5P2S2 | 3689-24-5 | 10 | NIOSH PEL TWA 0.2 ppm | 4 | 38 (Rat, 4 h) | ||
| Trifluoroacetyl chloride | C2ClF3O | 354-32-5 | ||||||
| Tungsten hexafluoride[16] | WF6 | 7783-82-6 | OSHA PEL TWA 2.5 ppm; ACGIH TLV TWA 3 ppm |
3 | 218 (Rat, 1 h) | |||
See also
editNotes
editReferences
edit- ^ "California Fire Code California Code of Regulations,Title 24, Part 9, Chapter 2 - Definitions" (PDF).
- ^ a b "Environmental Health and Radiation Safety Department at the University of Pennsylvania".
- ^ "Chemical Name Search". webbook.nist.gov. Retrieved 2021-11-10.
- ^ a b "CDC - NIOSH Pocket Guide to Chemical Hazards - Arsenic (inorganic compounds, as As)". www.cdc.gov. Retrieved 2021-11-10.
- ^ a b "Principles for the safe handling and distribution of highly toxic gases and mixtures" (PDF). Asia Industrial Gases Association. 2011-07-16. AIGA 026/06. Archived from the original (PDF) on 2011-07-16. Retrieved 2021-09-22.
- ^ "1988 OSHA PEL Project - Boron Tribromide | NIOSH | CDC". www.cdc.gov. 2020-02-25. Retrieved 2021-11-10.
- ^ PubChem. "Boron trichloride". pubchem.ncbi.nlm.nih.gov. Retrieved 2021-11-10.
- ^ a b "Boron Tribromide". Acute Exposure Guideline Levels for Selected Airborne Chemicals: Volume 17. 2014. doi:10.17226/18796. ISBN 978-0-309-30476-4.
- ^ Methyl bromide - OECD HPVMETHYL BROMIDE CAS N°: 74-83-9
- ^ Levin, B. C.; Paabo, M.; Gurman, J. L.; Harris, S. E.; Braun, E. (1987-12-01). "Toxicological interactions between carbon monoxide and carbon dioxide". Toxicology. 47 (1–2): 135–164. doi:10.1016/0300-483x(87)90165-x. ISSN 0300-483X. PMID 3120355.
- ^ Acute Exposure Guideline Levels for Selected Airborne Chemicals: Volume 6 (PDF). Environmental Protection Agency. 2007. ISBN 978-0-309-11214-7.
- ^ "Phosphorus(V) fluoride Safety Data Sheet". ThermoFisher Scientific. January 6, 2023.
- ^ "Silicon Tetrachloride Hazardous Substance Fact Sheet" (PDF). New Jersey Department of Health. October 2010.
- ^ "Stibine Hazardous Substance Fact Sheet" (PDF). New Jersey Department of Health and Senior Services. August 2001.
- ^ a b "Sulfur Tetrafluoride Safety Data Sheet" (PDF). Airgas.
- ^ "Tungsten Hexafluoride Safety Data Sheet" (PDF). Airgas.