- Synonyms: Destriol; 1,3,5-Estratriene-3-beta,16-alpha, 17-beta-triol; trihydroxyestrin
- OSHA IMIS Code Number: E321
- Chemical Abstracts Service (CAS) Registry Number: 50-27-1
- NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: KG8225000
- Chemical Description and Physical Properties:
- odorless white crystals
- molecular formula: C18H24O3
- molecular weight: 288.39
- melting point: 282°C
- Carcinogenic Classification:
- National Toxicology Program (NTP): Known to be a human carcinogen (estrogens, steroidal) (PDF)
- Potential Symptoms: IN MEN: Possible anorexia, nausea, vomiting, edema; feminization (gynecomastia, erectile dysfunction, hypogonadism, oligospermia); IN WOMEN: Breast tension or pain; cervical hypersecretion; menstrual disorders (menorrhagia, metrorrhagia); nausea, headache; fluid retention, hypertension, leg cramps, vision disturbances; endometriosis pain; possible decrease in milk production by lactating mothers
- Health Effects: Known human carcinogen (endometrial cancer) (HE2)
- Affected Organs: Male and female reproductive systems
- Estriol is an endogenous estrogenic hormone and is marketed in some countries as a treatment for climacteric symptoms (e.g., hot flashes, night sweating) in post-menopausal women.
- Estriol is synthesized from estradiol and estrone via the enzymes 17-hydroxysteroid dehydrogenase and 16α-hydroxylase. The mean production rates of estriol in 13 normal pre-menopausal women during the follicular and luteal phases of their cycle and in four post-menopausal women were reported to be 14, 23, and 11 µg/day, respectively. The mean (±SE) terminal half-life of estriol in plasma was 64±11 minutes.
- Affinities of estriol for the two known estrogen receptors, α and β, are only about 1/7 and 1/5, respectively, of the affinities of these receptors for estradiol-17β.
- Literature Basis:
- No Author: Estrogens, Steroidal (PDF). Report on Carcinogens (latest edition); U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program.
- No Author: Synapause-E3® 2 mg (tablets). South African Electronic Package Inserts.
- Kuiper, G.G.J.M., et al.: Comparison of the ligand binding specificity and transcript tissue distribution of estrogen receptors α and β. Endocrinology 138(3): 863-870, 1997.
- Longcope, C.: Estriol production and metabolism in normal women. J. Steroid Biochem. 20(4B): 959-962, 1984.
- Loose-Mitchell, D.S. and Stancel, G.M.: Estrogens and Progestins (Chapter 58). In, Goodman & Gilman's The Pharmacological Basis of Therapeutics, 10th Ed. J.G. Hardman, L.E. Limbird and A.G. Gilman, eds. New York: McGraw-Hill, 2001, pp. 1597-1634.
- Weiderpass, E., et al.: Low-potency oestrogen and risk of endometrial cancer: a case-control study. Lancet 353(9167): 1824-1828, 1999.
- Date Last Revised: 03/10/2006
Monitoring Methods used by OSHA
Primary Laboratory Sampling/Analytical Method (SLC1):
- Glass Fiber Filter (37 mm) in 3-piece cassette
- maximum volume: 240 Liters
- maximum flow rate: 1.0 L/min
- maximum time: 240 Minutes
- current analytical method: High Performance Liquid Chromatography; HPLC/UV at 280nm
- analytical solvent: Methanol
- method reference: OSHA Analytical Method (OSHA PV2001)
- method classification: Partially Validated
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