1,3­Dichloro­5,5­dimethylhydantoin

IDLH Documentation

CAS number: 118­52­5

NIOSH REL: 0.2 mg/m3 TWA, 0.4 mg/m3 STEL

Current OSHA PEL: 0.2 mg/m3 TWA

1989 OSHA PEL: 0.2 mg/m3 TWA, 0.4 mg/m3 STEL

1993-1994 ACGIH TLV: 0.2 mg/m3 TWA, 0.4 mg/m3 STEL

Description of Substance: White powder with a chlorine­like odor.

LEL:. . Unknown

Original (SCP) IDLH*: Unknown [*Note: "Effective" IDLH = 5 mg/m3 -- see discussion below.]

Basis for original (SCP) IDLH: Very little data are available on which to base an IDLH for 1,3­dichloro­5,5­dimethylhydantoin. For this draft technical standard, therefore, the respirators have been selected on the basis of the assigned protection factor afforded by each device up to 25 × the OSHA PEL of 0.2 mg/m3 (i.e., 5 mg/m3); only the "most protective" respirators are permitted for use in concentrations exceeding 5 mg/m3.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:


Species

Reference

LC50

LCLo

Time
Adjusted 0.5-hr

LC (CF)
Derived

value
Rat
Glyco 1981
-----
20,000 mg/m3
1 hr
25,000 mg/m3 (1.25)
2,500 mg/m3


Lethal dose data:


Species

Reference

Route
LD50

(mg/kg)
LDLo

(mg/kg)

Adjusted LD
Derived value
Rat

Rabbit

G. pig
Kay 1961/1962

Korolev et al. 1982

Korolev et al. 1982
oral

oral

oral
542

1,520

1,350
-----

-----

-----
3,794 mg/m3

10,640 mg/m3

9,450 mg/m3
379 mg/m3

1,064 mg/m3

945 mg/m3


Human data: None relevant for use in determining the revised IDLH.

Revised IDLH: 5 mg/m3

Basis for revised IDLH: 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).


REFERENCES:

1. Chrostek WJ, Cromer JW [1975]. Health hazard evaluation report HHE 73­160­206, Glyco Chemicals, Inc., Williamsport, PA. Cincinnati, OH: National Institute for Occupational Safety and Health, Division of Surveillance, Hazard Evaluations, and Field Studies.

2. Glyco Chemicals [1981]. 1,3­Dichloro­5,5­dimethyl­2,4­imidazolidinedione. In: TSCA 8(e) Submission to the U.S. Environmental Protection Agency (8EHQ­0281­0382). Williamsport,PA: Glyco® Chemicals, Inc.

3. Kay JH [1961/1962]. Unpublished technical reports. Northbrook, IL: Industrial Bio­Test Laboratories. (August 28, 1961; May 1, 1962).

4. Korolev AA, Vasilenko VE, et al. [1982]. Hygienic standard of dichloantine and the product of its transforation with dimethylhydantoin in water. Gig Sanit 47(6):76­78 (in Russian).
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