Technology Transfer Network - Air Toxics Web Site
Hazard Summary-Created in April 1992; Revised in January 2000
Exposure to phenol may occur from the use of some medicinal products (including
throat lozenges and ointments). Phenol is highly irritating
to the skin, eyes, and mucous membranes in humans after acute (short-term)
inhalation or dermal exposures. Phenol is considered to be quite
toxic to humans via oral exposure. Anorexia, progressive weight
loss, diarrhea, vertigo, salivation, a dark coloration of the urine, and
blood and liver effects have been reported in chronically (long-term)
exposed humans. Animal studies have reported reduced fetal body
weights, growth retardation, and abnormal development in the offspring
of animals exposed to phenol by the oral route. EPA has classified
phenol as a Group D, not classifiable as to human carcinogenicity.
Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS), which contains information on oral chronic toxicity and the RfD and the carcinogenic effects of phenol, and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profile for Phenol.
- The primary use of phenol is in the production of phenolic resins, which are used in the plywood, construction, automotive, and appliance industries. (1)
- Phenol is also used in the production of caprolactam and bisphenol A, which are intermediates in the manufacture of nylon and epoxy resins, respectively. (1)
- Other uses of phenol include as a slimicide, as a disinfectant, and in medicinal products such as ear and nose drops, throat lozenges, and mouthwashes. (1)
Sources and Potential Exposure
- Individuals may be exposed to phenol through breathing contaminated air or through skin contact in the workplace. (1)
- Other exposures to phenol may occur through the use of phenol-containing medicinal products (including mouthwashes, toothache drops, throat lozenges, analgesic rubs, and antiseptic lotions) or smoking tobacco. (1)
Assessing Personal Exposure
- Phenol can be detected in urine; this test can be used to determine whether a person has recently been exposed to phenol or to substances that are changed to phenol in the body. However, no test will tell whether a person has been exposed only to phenol, because many substances are changed to phenol in the body. (1)
Health Hazard InformationAcute Effects:
- Inhalation and dermal exposure to phenol is highly irritating to the skin, eyes, and mucous membranes in humans. (1-3)
- Symptoms of acute toxicity in humans include irregular breathing, muscle weakness and tremors, loss of coordination, convulsions, coma, and respiratory arrest at lethal doses. (1-3)
- Acute animal tests in rats, mice, and rabbits have shown phenol to have high acute toxicity from oral exposure. (4)
- Anorexia, progressive weight loss, diarrhea, vertigo, salivation, and a dark coloration of the urine have been reported in chronically exposed humans. Gastrointestinal irritation and blood and liver effects have also been reported. (1)
- In one study, muscle pain, weakness, enlarged liver and elevated levels of liver enzymes were found in an individual after inhalation and dermal exposure to phenol and a few other chemicals. (1)
- Application of phenol to the skin results in dermal inflammation and necrosis. Cardiac arrhythmias have also been reported in humans exposed to high concentrations of phenol. (1)
- Chronic inhalation exposure of animals to phenol has shown central nervous systems (CNS), kidney, liver, respiratory, and cardiovascular effects. (1)
- The Reference Dose (RfD) for phenol is 0.6 milligrams per kilogram body weight per day (mg/kg/d) based on reduced fetal body weights in rats. The RfD is an estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to the human population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious noncancer effects during a lifetime. It is not a direct estimator of risk but rather a reference point to gauge the potential effects. At exposures increasingly greater than the RfD, the potential for adverse health effects increases. Lifetime exposure above the RfD does not imply that an adverse health effect would necessarily occur. (5)
- EPA has low confidence in the study on which the RfD was based because the dose was administered by gavage; medium confidence in the database because it contains several supporting studies (subchronic, chronic, and reproductive/ developmental); and, consequently, low-to-medium confidence in the RfD. (5)
- EPA has established a provisional Reference Concentration (RfC) for phenol of 0.006 milligrams per cubic meter (mg/m3) based on no effects in rats, mice, or monkeys. The provisional RfC is a value that has had some form of Agency review, but it does not appear on IRIS. (13)
- No studies were located concerning the developmental or reproductive effects of phenol in humans.
- Animal studies have reported reduced fetal body weights, growth retardation, and abnormal development in the offspring of animals exposed to phenol by the oral route. Decreased maternal weight gain and increased maternal mortality were also observed. (1,3,5)
- Small, non-significant excesses in certain types of cancers were reported in occupationally exposed workers; however, these effects were not clearly related to phenol exposure. (1)
- Animal studies have not seen tumors resulting from oral exposure to phenol, while dermal studies have reported that phenol applied to the skin may be a tumor promotor and/or a weak skin carcinogen in mice. (1,2,5)
- EPA has classified phenol as a Group D, not classifiable as to human carcinogenicity, based on a lack of data concerning carcinogenic effects in humans and animals. (5)
- Phenol is a colorless or white solid when it is pure; however, it is usually sold and used as a liquid. (1)
- The odor threshold for phenol is 0.04 parts per million (ppm), with a strong very sweet odor reported. (1,7)
- Phenol is very soluble in water and is quite flammable. (2)
- The chemical formula for phenol is C6H6O and the molecular weight is 94.1 g/mol. (8,9)
- The vapor pressure for phenol is 0.3513 mm Hg at 25 °C, and it has a log octanol/water partition coefficient (log Kow) of 1.46. (1)
Conversion Factors (only for the gaseous form):
To convert concentrations in air (at 25 °C) from ppm to mg/m3: mg/m3 = (ppm) × (molecular weight of the compound)/(24.45). For phenol: 1 ppm = 3.85 mg/m3.
Health Data from Inhalation Exposure
AIHA ERPG--American Industrial Hygiene Association's emergency
response planning guidelines. ERPG 1 is the maximum airborne concentration
below which it is believed nearly all individuals could be exposed up
to one hour without experiencing other than mild transient adverse health
effects or perceiving a clearly defined objectionable odor; ERPG 2 is
the maximum airborne concentration below which it is believed nearly all
individuals could be exposed up to one hour without experiencing or developing
irreversible or other serious health effects that could impair their abilities
to take protective action.
ACGIH TLV--American Conference of Governmental and Industrial Hygienists' threshold limit value expressed as a time-weighted average; the concentration of a substance to which most workers can be exposed without adverse effects.
NIOSH ceiling--National Institute of Occupational Safety and Health's recommended exposure limit ceiling; the concentration that should not be exceeded at any time.
NIOSH IDLH -- NIOSH's immediately dangerous to life or health concentration; NIOSH recommended exposure limit to ensure that a worker can escape from an exposure condition that is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from the environment.
NIOSH REL--NIOSH's recommended exposure limit; NIOSH-recommended exposure limit for an 8- or 10-h time-weighted-average exposure and/or ceiling.
OSHA PEL--Occupational Safety and Health Administration's permissible exposure limit expressed as a time-weighted average; the concentration of a substance to which most workers can be exposed without adverse effect averaged over a normal 8-h workday or a 40-h workweek.
The health and regulatory values cited in this factsheet were obtained
in December 1999.
a Health numbers are toxicological numbers from animal testing or risk assessment values developed by EPA.
b Regulatory numbers are values that have been incorporated in Government regulations, while advisory numbers are nonregulatory values provided by the Government or other groups as advice. OSHA numbers are regulatory, whereas NIOSH, ACGIH, and AIHA numbers are advisory.
- Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for Phenol (Update). Public Health Service, U.S. Department of Health and Human Services, Atlanta, GA. 1998.
- E.J. Calabrese and E.M. Kenyon. Air Toxics and Risk Assessment. Lewis Publishers, Chelsea, MI. 1991.
- U.S. Department of Health and Human Services. Hazardous Substances Data Bank (HSDB, online database). National Toxicology Information Program, National Library of Medicine, Bethesda, MD. 1993.
- U.S. Department of Health and Human Services. Registry of Toxic Effects of Chemical Substances (RTECS, online database). National Toxicology Information Program, National Library of Medicine, Bethesda, MD. 1993.
- U.S. Environmental Protection Agency. Integrated Risk Information System (IRIS) on Phenol. National Center for Environmental Assessment, Office of Research and Development, Washington, DC. 1999.
- American Industrial Hygiene Association (AIHA). The AIHA 1998 Emergency Response Planning Guidelines and Workplace Environmental Exposure Level Guides Handbook. 1998.
- J.E. Amoore and E. Hautala. Odor as an aid to chemical safety: Odor thresholds compared with threshold limit values and volatilities for 214 industrial chemicals in air and water dilution. Journal of Applied Toxicology, 3(6):272-290. 1983.
- U.S. Environmental Protection Agency. Drinking Water Health Advisory on Phenol. Office of Drinking Water, Washington, DC. 1990.
- U.S. Environmental Protection Agency. Health and Environmental Effects Profile for Phenol. EPA/600/x-87/121. Environmental Criteria and Assessment Office, Office of Health and Environmental Assessment, Office of Research and Development, Cincinnati, OH. 1987.
- American Conference of Governmental Industrial Hygienists (ACGIH). 1999 TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents. Biological Exposure Indices. Cincinnati, OH. 1999.
- National Institute for Occupational Safety and Health (NIOSH). Pocket Guide to Chemical Hazards. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention. Cincinnati, OH. 1997.
- Occupational Safety and Health Administration (OSHA). Occupational Safety and Health Standards, Toxic and Hazardous Substances. Code of Federal Regulations 29 CFR 1910.1000. 1998.
- U.S. EPA (Environmental Protection Agency). Hazardous waste management system; identification and listing of hazardous waste; solvents; final rule. Federal Register 63 FR 64371- 402. 1998.