Introduction
Phenol is a colorless or white solid when it is pure. It is usually sold and used, however, as a liquid. It has a strong odor that is sickeningly sweet and irritating. It evaporates more slowly than water and dissolves fairly well in water. Phenol can catch on fire.
Phenol is mainly a man-made chemical, although it is found in nature in animal wastes and organic material. The largest single use of phenol is to make plastics, but it also is used to make caprolactam (used to make nylon 6 and other man-made fibers) and bisphenol A (used to make epoxy and other resins). It also is used as a slimicide (a chemical that kills bacteria and fungi found in watery slimes), as a disinfectant, and in medical products.
Fate & Transport
Small, single releases of phenol do not stay long in the air (usually half is removed in less than 1 day), and usually do not stay in the soil for long periods (usually completely gone in 2-5 days), but can stay in water for longer than 9 days. Phenol will stay in the air, soil, and water for much longer times if a large amount of it is released at one time, or if a steady amount is released over a long time. More phenol than is usually found in the environment has been found in surface waters and surrounding air that were contaminated when phenol was released from industries and commercial products that contain phenol. Phenol has been found in materials released from landfills and hazardous waste sites, and it has been found in the groundwater near these sites. Phenol is usually found in the environment below 100 parts per billion (ppb), although much higher levels have been reported. One ppb or less of phenol has been found in relatively unpolluted surface and ground waters.
Exposure Pathways
Because phenol is used in many manufacturing processes and in many products, exposure to phenol may take place where you work or in very low amounts at home. Phenol is present in a number of consumer products which are swallowed, rubbed on, or added to various parts of the body. These include ointments, ear and nose drops, cold sore lotions, mouthwashes, gargles, toothache drops, analgesic rubs, throat lozenges, and antiseptic lotions. Phenol has been found in drinking water, air, automobile exhaust, tobacco smoke, marijuana smoke, and certain foods including smoked summer sausage, fried chicken, mountain cheese, and some species of fish.
Phenol has not been reported in soil except at hazardous waste sites; this is probably due to the fact that phenol does not remain in soil for very long, rather than the fact that it never occurs there. At this time, phenol has been found at at least 184 of 1177 hazardous waste sites on the National Priorities List (NPL) in the United States.
Exposure to phenol at the workplace may occur through breathing contaminated air or through skin contact with phenol when it is made and used. Exposures may be higher than outside the workplace.
In addition to workplace exposures, other possible exposures include breathing contaminated air, tobacco smoking or environmental tobacco smoke exposure, drinking water from contaminated surface or groundwater supplies, swallowing products containing phenol, and coming into contact with contaminated water and products containing phenol when bathing or putting lotions on the skin. The use of medical products and other consumer products that contain phenol usually accounts for much more of your total exposure to phenol than releases in the workplace and outdoors. These exposures, however, may not occur often and are usually over short periods of time. Populations living near phenol spills, waste disposal, or landfill sites may be at risk for higher exposures to phenol than other populations. If phenol is at a waste site near homes that use wells as a source of water, the well water could be contaminated. If phenol is spilled at a waste site, people, such as children playing in dirt containing phenol, may have skin contact or swallow soil or water contaminated with phenol. Skin contact with phenol or swallowing products containing phenol may lead to increased exposure, but this exposure may not occur often and is usually over short periods of time.
Metabolism
Phenol can enter the body when a person drinks contaminated water, eats contaminated food, or swallows products that have phenol in them. Phenol spilled on the skin easily enters the body through the skin. Phenol also enters the body through the lungs when a person smokes or breathes in air or smoke that contains phenol.
The amount of phenol that will enter the body from skin contact with water that contains phenol depends on how much phenol is in the water, how long it touches the skin, and how much skin touches the contaminated water. If a person is exposed to air that contains phenol, phenol can enter the body through the skin and lungs. The skin may take in as much as one-half the phenol that enters the body when a person is exposed to phenol in air. Studies in humans and animals show that most phenol that enters the body through the skin, by breathing contaminated air, or eating food, drinking water, or taking products that contain phenol leaves the body in the urine within 24 hours.
Health Effects
The serious effects of a harmful substance usually increase as both the level and length of exposure increase. Repeated exposure to low levels of phenol in drinking water has been linked with diarrhea and mouth sores in humans; eating very large amounts of phenol has resulted in death. Laboratory animals that drank very large amounts of phenol in water had muscle tremors and loss of coordination.
The effects on humans of breathing phenol in air are unknown. Exposure of animals to high levels of phenol in air for a few minutes is irritating to the lungs, and repeated exposure for several days causes muscle tremors and loss of coordination. Exposure to high levels of phenol for several weeks results in paralysis and severe injury to the heart, kidneys, liver, and lungs, followed by death in some cases.
When exposures involve the skin surface, the size of the total exposed skin can influence the severity of the toxic effects. Small amounts of phenol put on the skin of animals for short times can cause blisters and burns on the exposed area, and spilling weak phenol solutions on large parts of the body (more than 25% of the body surface) can result in death.
The effects of exposure to phenol on human reproduction and the developing fetus are unknown. Pregnant animals that drank water containing high amounts of phenol gave birth to offspring that had low birth weights and birth defects. We do not know whether phenol causes cancer in humans, but cancer occurs in mice when phenol is put on the skin. When phenol is combined with other chemicals that cause cancer and put on the skin, more cancer may occur than when the other chemicals are put on alone.
Phenol can have positive effects when used for medical reasons. It is an antiseptic (kills germs) when put on the skin and may also have antiseptic properties when gargled as a mouthwash. It is an anesthetic (relieves pain) and is a part of some sore-throat remedies (lozenges and formulas). Small amounts of phenol in water have been injected into nerves to reduce pain caused by some nerve disorders. Phenol will kill the outer layers of skin if it remains on the skin, and small amounts of strong solutions of phenol are sometimes put on the skin to remove warts and to treat other skin spots and disorders.
Regulations
The Environmental Protection Agency (EPA) has decided that waters (lakes, streams) should be limited to 0.3 milligrams phenol per liter of water (0.3 mg/L) to protect human health from the possible harmful effects of exposure to phenol by drinking water and eating contaminated water plants and animals. The Occupational Safety and Health Administration (OSHA) has set a limit of 5 parts of phenol per million parts of workroom air (5 ppm) to protect workers during 8-hour workshifts in a 40-hour workweek. The National Institute for Occupational Safety and Health (NIOSH) recommends that the amount of phenol in workroom air be limited to 5 ppm over a 10-hour workshift, and that the workroom air should not contain more than 16 ppm during a 15-minute period.