*** CHEMICAL IDENTIFICATION ***
RTECS NUMBER : NI8615000
CHEMICAL NAME : Imidazole-2-thiol, 1-methyl-
CAS REGISTRY NUMBER : 60-56-0
LAST UPDATED : 199710
DATA ITEMS CITED : 29
MOLECULAR FORMULA : C4-H6-N2-S
MOLECULAR WEIGHT : 114.18
WISWESSER LINE NOTATION : T5N CNJ A BSH
COMPOUND DESCRIPTOR : Tumorigen
Drug
Mutagen
Reproductive Effector
Human
SYNONYMS/TRADE NAMES :
* Basolan
* Danantizol
* Favistan
* Frentirox
* Imidazole, 1-methyl-2-mercapto-
* Imidazole-2-thio, 1-methyl-
* Mercaptazole
* 2-Mercapto-1-methylimidazole
* Mercasolyl
* Mercazole
* Mercazolyl
* Merkazolil
* Metazolo
* Methiamazole
* Methimazol
* Methimazole
* 1-Methylimidazole-2-thiol
* Methylmercaptoimidazole
* 1-Methyl-2-mercaptoimidazole
* Metizol
* Metothyrine
* 1-Metylo 2 merkaptoimidazolem
* Strumazole
* Tapazole
* Thacapzol
* Thiamazole
* Thycapzol
* USAF EL-30
*** HEALTH HAZARD DATA ***
** ACUTE TOXICITY DATA **
TYPE OF TEST : LD50 - Lethal dose, 50 percent kill
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 2250 mg/kg
TOXIC EFFECTS :
Peripheral Nerve and Sensation - spastic paralysis with or without sensory
change
Behavioral - somnolence (general depressed activity)
Behavioral - tremor
REFERENCE :
ARZNAD Arzneimittel-Forschung. Drug Research. (Editio Cantor Verlag,
Postfach 1255, W-7960 Aulendorf, Fed. Rep. Ger.) V.1- 1951-
Volume(issue)/page/year: 4,20,1954
TYPE OF TEST : LD50 - Lethal dose, 50 percent kill
ROUTE OF EXPOSURE : Subcutaneous
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 1050 mg/kg
TOXIC EFFECTS :
Details of toxic effects not reported other than lethal dose value
REFERENCE :
FRPSAX Farmaco, Edizione Scientifica. (Casella Postale 227, 27100 Pavia,
Italy) V.8-43 1953-88 For publisher information, see FRMCE8
Volume(issue)/page/year: 14,54,1959
TYPE OF TEST : LD50 - Lethal dose, 50 percent kill
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - mouse
DOSE/DURATION : 860 mg/kg
TOXIC EFFECTS :
Peripheral Nerve and Sensation - spastic paralysis with or without sensory
change
Behavioral - somnolence (general depressed activity)
Behavioral - tremor
REFERENCE :
ARZNAD Arzneimittel-Forschung. Drug Research. (Editio Cantor Verlag,
Postfach 1255, W-7960 Aulendorf, Fed. Rep. Ger.) V.1- 1951-
Volume(issue)/page/year: 4,20,1954
TYPE OF TEST : LD50 - Lethal dose, 50 percent kill
ROUTE OF EXPOSURE : Intraperitoneal
SPECIES OBSERVED : Rodent - mouse
DOSE/DURATION : 500 mg/kg
TOXIC EFFECTS :
Details of toxic effects not reported other than lethal dose value
REFERENCE :
NTIS** National Technical Information Service. (Springfield, VA 22161)
Formerly U.S. Clearinghouse for Scientific & Technical Information.
Volume(issue)/page/year: AD277-689
TYPE OF TEST : LD50 - Lethal dose, 50 percent kill
ROUTE OF EXPOSURE : Subcutaneous
SPECIES OBSERVED : Rodent - mouse
DOSE/DURATION : 345 mg/kg
TOXIC EFFECTS :
Peripheral Nerve and Sensation - spastic paralysis with or without sensory
change
Behavioral - somnolence (general depressed activity)
Behavioral - tremor
REFERENCE :
ARZNAD Arzneimittel-Forschung. Drug Research. (Editio Cantor Verlag,
Postfach 1255, W-7960 Aulendorf, Fed. Rep. Ger.) V.1- 1951-
Volume(issue)/page/year: 4,20,1954
** OTHER MULTIPLE DOSE TOXICITY DATA **
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 580 mg/kg/1W-C
TOXIC EFFECTS :
Endocrine - evidence of thyroid hypofunction
Endocrine - changes in thyroid weight
Nutritional and Gross Metabolic - weight loss or decreased weight gain
REFERENCE :
JCEMAZ Journal of Clinical Endocrinology and Metabolism. (Williams &
Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.12- 1952-
Volume(issue)/page/year: 32,659,1971
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 2400 mg/kg/12D-I
TOXIC EFFECTS :
Related to Chronic Data - death
REFERENCE :
ARZNAD Arzneimittel-Forschung. Drug Research. (Editio Cantor Verlag,
Postfach 1255, W-7960 Aulendorf, Fed. Rep. Ger.) V.1- 1951-
Volume(issue)/page/year: 4,20,1954
** TUMORIGENIC DATA **
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 1100 mg/kg/2Y-C
TOXIC EFFECTS :
Tumorigenic - neoplastic by RTECS criteria
Lungs, Thorax, or Respiration - tumors
Endocrine - thyroid tumors
REFERENCE :
FCTXAV Food and Cosmetics Toxicology. (London, UK) V.1-19, 1963-81. For
publisher information, see FCTOD7. Volume(issue)/page/year: 11,649,1973
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - mouse
DOSE/DURATION : 33 gm/kg/1Y-C
TOXIC EFFECTS :
Tumorigenic - neoplastic by RTECS criteria
Lungs, Thorax, or Respiration - tumors
Endocrine - thyroid tumors
REFERENCE :
CANCAR Cancer (Philadelphia). (Lippincott/Harper, Journal Fulfillment
Dept., 2350 Virginia Ave., Hagerstown, MD 21740) V.1- 1948-
Volume(issue)/page/year: 40,2188,1977
TYPE OF TEST : TD - Toxic dose (other than lowest)
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE/DURATION : 2700 mg/kg/26W-C
TOXIC EFFECTS :
Tumorigenic - neoplastic by RTECS criteria
Endocrine - thyroid tumors
REFERENCE :
CRSBAW Comptes Rendus des Seances de la Societe de Biologie et de Ses
Filiales. (SPPIF, B.P.22, F-41353 Vineuil, France) V.1- 1849-
Volume(issue)/page/year: 174,268,1980
** REPRODUCTIVE DATA **
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Unreported
SPECIES OBSERVED : Human - woman
DOSE : 145 mg/kg
SEX/DURATION : female 1-34 week(s) after conception
TOXIC EFFECTS :
Reproductive - Specific Developmental Abnormalities - other developmental
abnormalities
REFERENCE :
ZEGYAX Zentralblatt fuer Gynaekologie. (Johann Ambrosius Barth Verlag,
Postfach 109, DDR-7010, Leipzig, Ger. Dem. Rep.) V.1- 1877-
Volume(issue)/page/year: 88,218,1966
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 80 mg/kg
SEX/DURATION : female 17-22 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - behavioral
REFERENCE :
TJADAB Teratology, The International Journal of Abnormal Development. (Alan
R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.1- 1968-
Volume(issue)/page/year: 31,64A,1985
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 600 mg/kg
SEX/DURATION : female 15-22 day(s) after conception
lactating female 7 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - biochemical and metabolic
REFERENCE :
TJADAB Teratology, The International Journal of Abnormal Development. (Alan
R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.1- 1968-
Volume(issue)/page/year: 29(2),4B,1984
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 320 mg/kg
SEX/DURATION : female 17-22 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Specific Developmental Abnormalities - Central Nervous System
Reproductive - Specific Developmental Abnormalities - endocrine system
REFERENCE :
APTOD9 Abstracts of Papers, Society of Toxicology. Annual Meetings.
(Academic Press, Inc., 1 E. First St., Duluth, MN 55802)
Volume(issue)/page/year: 19,A30,1980
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 1100 mg/kg
SEX/DURATION : female 1-22 day(s) after conception
TOXIC EFFECTS :
Reproductive - Maternal Effects - parturition
Reproductive - Effects on Newborn - stillbirth
Reproductive - Effects on Newborn - live birth index (measured after birth)
REFERENCE :
PIAIA9 Proceedings of the Iowa Academy of Science. (Iowa Academy of
Science, Exec. Dir., Univ. of Northern Iowa, Cedar Falls, IA 50613) V.1-
1887/93- Volume(issue)/page/year: 72,462,1965
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 160 mg/kg
SEX/DURATION : female 17-22 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - growth statistics (e.g.%, reduced weight
gain)
Reproductive - Effects on Newborn - behavioral
REFERENCE :
TJADAB Teratology, The International Journal of Abnormal Development. (Alan
R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.1- 1968-
Volume(issue)/page/year: 27,79A,1983
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - rat
DOSE : 567 mg/kg
SEX/DURATION : female 17-22 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - physical
REFERENCE :
TXAPA9 Toxicology and Applied Pharmacology. (Academic Press, Inc., 1 E.
First St., Duluth, MN 55802) V.1- 1959- Volume(issue)/page/year:
63,133,1982
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Subcutaneous
SPECIES OBSERVED : Rodent - rat
DOSE : 1530 ug/kg
SEX/DURATION : female 18-20 day(s) after conception
TOXIC EFFECTS :
Reproductive - Effects on Embryo or Fetus - other effects to embryo
REFERENCE :
AJPHAP American Journal of Physiology. (American Physiological Soc., 9650
Rockville Pike, Bethesda, MD 20814) V.1- 1898- Volume(issue)/page/year:
257,L94,1989
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - mouse
DOSE : 320 mg/kg
SEX/DURATION : female 16-21 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - growth statistics (e.g.%, reduced weight
gain)
Reproductive - Effects on Newborn - behavioral
REFERENCE :
TJADAB Teratology, The International Journal of Abnormal Development. (Alan
R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.1- 1968-
Volume(issue)/page/year: 27,71A,1983
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - mouse
DOSE : 320 mg/kg
SEX/DURATION : female 16-21 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Newborn - behavioral
REFERENCE :
NTOTDY Neurobehavioral Toxicology and Teratology. (Fayetteville, NY) V.3-8,
1981-86. For publisher information, see NETEEC. Volume(issue)/page/year:
8,69,1986
TYPE OF TEST : TDLo - Lowest published toxic dose
ROUTE OF EXPOSURE : Oral
SPECIES OBSERVED : Rodent - mouse
DOSE : 1152 mg/kg
SEX/DURATION : female 16-21 day(s) after conception
lactating female 10 day(s) post-birth
TOXIC EFFECTS :
Reproductive - Effects on Embryo or Fetus - fetotoxicity (except death,
e.g., stunted fetus)
Reproductive - Effects on Newborn - behavioral
REFERENCE :
FAATDF Fundamental and Applied Toxicology. (Academic Press, Inc., 1 E.
First St., Duluth, MN 55802) V.1- 1981- Volume(issue)/page/year:
8,531,1987
** MUTATION DATA **
TYPE OF TEST : Mutation test systems - not otherwise specified
TEST SYSTEM : Human Lymphocyte
DOSE/DURATION : 2500 ug/L
REFERENCE :
HUMAA7 Humangenetik. (Heidelberg, Fed. Rep. Ger.) V.1-30, 1964-75. For
publisher information, see HUGEDQ. Volume(issue)/page/year: 26,155,1975
TYPE OF TEST : Cytogenetic analysis
TEST SYSTEM : Rodent - mouse Mammary gland
DOSE/DURATION : 3200 umol/L/24H (Continuous)
REFERENCE :
JTSCDR Journal of Toxicological Sciences. (Japanese Soc. of Toxicological
Sciences, 4th Floor, Gakkai Center Bldg., 4-16, Yayoi 2-chome, Bunkyo-ku,
Tokyo 113, Japan) V.1- 1976- Volume(issue)/page/year: 5,141,1980
TYPE OF TEST : Sister chromatid exchange
ROUTE OF EXPOSURE : Oral
TEST SYSTEM : Rodent - mouse
DOSE/DURATION : 28 mg/kg/2W (Continuous)
REFERENCE :
MUREAV Mutation Research. (Elsevier Science Pub. B.V., POB 211, 1000 AE
Amsterdam, Netherlands) V.1- 1964- Volume(issue)/page/year: 326,193,1995
*** REVIEWS ***
TOXICOLOGY REVIEW
PCNAA8 Pediatric Clinics of North America. (W.B. Saunders Co., W.
Washington Sq., Philadelphia, PA 19105) V.1- 1954-
Volume(issue)/page/year: 8,413,1961
*** NIOSH STANDARDS DEVELOPMENT AND SURVEILLANCE DATA ***
NIOSH OCCUPATIONAL EXPOSURE SURVEY DATA :
NOHS - National Occupational Hazard Survey (1974)
NOHS Hazard Code - 83970
No. of Facilities: 33 (estimated)
No. of Industries: 1
No. of Occupations: 1
No. of Employees: 297 (estimated)
NOES - National Occupational Exposure Survey (1983)
NOES Hazard Code - 83970
No. of Facilities: 23 (estimated)
No. of Industries: 2
No. of Occupations: 4
No. of Employees: 707 (estimated)
No. of Female Employees: 239 (estimated)
*** STATUS IN U.S. ***
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JUNE 1998
*** END OF RECORD ***