Chlorine

Agent Name
Chlorine
CAS Number
7782-50-5
Formula
Cl2
Major Category
Toxic Gases & Vapors
Synonyms
Molecular chlorine; [NIOSH] Bertholite; [ChemIDplus] UN1017
Category
Oxidizers
Description
Greenish-yellow gas with a pungent, irritating odor; Note: Shipped as a liquefied compressed gas; [NIOSH] Vapor density = 2.48 (heavier than air); [HSDB]
Sources/Uses
Used in water purification, paper manufacturing, and the synthesis of chlorinated hydrocarbons; [Levy, p. 409] Also used in shrink-proofing wool; [ACGIH]
Comments
“The TLV-STEL is based on D’Alessandro et al. (1996) findings of significant pulmonary function changes in 10 human volunteers, 5 with airway hyper-reactivity (AHR) and 5 without AHR after 60-minute exposures to 1 ppm Cl2. Lung function changes did not persist when measured after 24 hours.” [ACGIH] Liquid causes first degree burns on short exposure; [CHRIS] Listed as one of "major irritant airborne toxicants"; [LaDou, p. 563] Possible frostbite from contact with liquid; [NIOSH] When spilled in water “Chlorine dioxide, hydrate, frozen” can release large amounts of Chlorine. [ERG 2016] A lachrymator; [CHEMINFO] Causes lachrymation; [ICSC] Chlorine is fibrogenic to the lungs in the context of an acute inhalation exposure complicated by bronchiolitis obliterans.
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
Insufficient data
TIH
Yes
TLV (ACGIH)
0.1 ppm
STEL (ACGIH)
0.4 ppm
PEL (OSHA)
Ceiling(OSHA) = 1 ppm
MAK
0.5 ppm
IDLH (NIOSH)
10 ppm
Excerpts from Documentation for IDLHs
Exposures to 30 ppm have been reported to cause intense coughing fits and exposure to 40 to 60 ppm for 30 to 60 minutes or more may cause serious damage [ILO 1971]. A concentration of 34 to 51 ppm has been reported to be lethal in 1 to 1.5 hours [Freitag 1941] while 14 to 21 ppm has been suggested as being dangerous within 0.5 to 1 hour [NPIRI 1983].
Odor Threshold Low
0.2 ppm
Odor Threshold High
0.4 ppm
RD50
9 ppm
Lethal Concentration
LC50 (rat) = 293 ppm/1 hr
Explanatory Notes
Mean detection odor threshold = 0.080 ppm; [AIHA]; Odor threshold = 0.2 to 0.4 ppm; [ACGIH]
Half Life
No reports found; [TDR, p. 308]
Reference Link #2
NFPA
will not burn
ERPG-1
1 ppm
ERPG-2
3 ppm
ERPG-3
20 ppm

Adverse Effects

Chronic Bronchitis
Yes
Lachrymator
Yes
Toxic Pneumonitis
Yes
Fibrogenic
Yes
Dermatotoxin
Skin burns
ACGIH Carcinogen
Not Classifiable

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent:

Activities

Activities with risk of exposure: