1,3-Dichloro-5,5-dimethylhydantoin
Agent Name
1,3-Dichloro-5,5-dimethylhydantoin
CAS Number
118-52-5
Formula
C5-H6-Cl2-N2-O2
Major Category
Nitrogen Compounds
Synonyms
1,3-Dichloro-5,5'-methylhydantoin; 1,3-Dichloro-5,5-dimethyl hydantoin; 1,3-Dichloro-5,5-dimethyl-2,4-imidazolidinedione; 1,3-Dichloro-5,5-dimethylhydantoin; 1,3-Dwuchloro-5,5-dwumetylohydantoina [Polish]; 2,4-Imidazolidinedione, 1,3-dichloro-5,5-dimethyl-; DDH; Dactin; Daktin; Dantoin; Dichlorantin; Dwuchlorantyny [Polish]; Halane; Hydan; Hydan (antiseptic); Hydantoin, dichlorodimethyl-; Omchlor; [ChemIDplus] UN8027
Category
Other Nitrogen Compounds
Description
White powder with a chlorine-like odor; [NIOSH]
Sources/Uses
Used as a chlorinating agent, for organic synthesis, and to stabilize vinyl chloride polymers; [ACGIH] Used as a disinfectant and industrial deodorant; used in water treatment and laundry bleaches; [HSDB]
Comments
Hypochlorous acid is released upon contact with water. A concentration of 10 ppm is the maximum level recommended to prevent respiratory irritation when used to sanitize swimming pools. A worker exposed to a concentration exceeding 0.2 mg/m3 complained of cough and chest discomfort. [ACGIH] Corrosive to skin and eyes; May cause respiratory sensitization; [Sigma-Aldrich MSDS]
Reference Link #1
Biomedical References
Exposure Assessment
Skin Designation (ACGIH)
Insufficient data
TLV (ACGIH)
0.2 mg/m3
STEL (ACGIH)
0.4 mg/m3
PEL (OSHA)
0.2 mg/m3
IDLH (NIOSH)
5 mg/m3
Excerpts from Documentation for IDLHs
Based on health considerations and acute oral toxicity data in animals [Kay 1961/62; Korolev et al. 1982], a value of about 500 mg/m3 would have been appropriate for 1,3dichloro5,5dimethylhydantoin. However, the revised IDLH for 1,3dichloro5,5dimethylhydantoin is 5 mg/m3 based on being 25 times the NIOSH REL and OSHA PEL of 0.2 mg/m3 (25 is an assigned protection factor for respirators and was used during the Standards Completion Program for deciding when the "most protective" respirators should be used for 1,3dichloro5,5dimethylhydantoin).
Vapor Pressure
2.4E-05 mm Hg
Odor Threshold Low
0.01 ppm
Lethal Concentration
LCLo (rat) = 20,000 mg/m3/1H
Explanatory Notes
Odor threshold from "Quick Guide: The Electronic NIOSH Pocket Guide to Chemical Hazards"; Flash point = 346 deg F;
Adverse Effects
Toxic Pneumonitis
Yes
Dermatotoxin
Skin burns
Diseases, Processes, and Activities Linked to This Agent
Processes
Industrial Processes with risk of exposure: