Description

Three types (or isomers) of cresols exist: ortho-cresol, meta -cresol, and para-cresol; abbreviated as o-cresol, m-cresol, and p-cresol.

Pure cresols are solid, while mixtures tend to be liquid.

Cresols have a medicinal smell.

Uses

• Manufacturing

Cresols are both manufactured chemicals and natural components in many foods. Large amounts of cresols are produced in the United States.

Cresols are used to manufacture other chemicals and as solvents.

• Consumer products

Cresols kill microorganisms and are added to soaps as disinfectants.

Sources

Cresols are released to the environment during the burning of wood, coal, and fossil fuels, as well as from their manufacture and the use of products containing cresols.

Break down

• Air

Cresols are quickly broken down in the air, usually within 1–2 days. They can also be removed from the air by rain.

• Water

Cresols in water are degraded within days by microorganisms.

• Soil

Cresols are degraded rapidly in soil by microorganisms, but a portion may move into groundwater.

Air—primary source of exposure

The primary way you can be exposed to cresols is by breathing air containing them. Releases of cresols into the air occur from:

• industries using or manufacturing cresols
• automobile exhaust
• cigarette smoke
• wood and trash burning

A national emissions study conducted from 1990 to 1998 reported an average county-level concentration of 31.7 nanograms per cubic meter (ng/m³) for all cresol isomers combined.

Water

Cresols have been detected in surface waters and groundwater, but generally at low levels (approximately 1 microgram per liter [µg/L] or less).

Higher levels have been detected:

• where petroleum spills have occurred
• near hazardous waste sites
• in industrial effluents

Workplace

A large number of workers are potentially exposed to cresols. Potential exposures occur in:

• manufacture of cresols
• chemical laboratories
• coal gasification facilities
• paint and varnish application
• application of insulation lacquers to copper wires
• wood-preserving facilities

Exposure may occur through breathing and dermal contact with contaminated air and/or liquid cresols or products containing cresols.

Food

Low levels of cresols have been found in some foods such as tomatoes, tomato ketchup, asparagus, cheeses, butter, bacon, and smoked foods.

Some drinks also contain cresols (coffee, black tea, wine, Scotch whisky, brandy, and rum).

Consumer products

Exposure may occur through accidental or intentional ingestion or contact of the skin with cleaners or disinfectants containing cresols.

Enter your body

• Inhalation

There is no information to determine whether cresols can enter the bloodstream through your lungs if you breathe air contaminated with these substances.

• Ingestion

Cresols in food or water may rapidly enter your body through the digestive tract.

• Dermal Contact

Cresols may enter through your skin when you come into contact with liquids containing cresols.

Leave your body

Once in your body, cresols are transformed into other chemicals called metabolites. Most of these metabolites leave your body in the urine within 1 day.

Humans

• Inhalation

Brief exposures to 6 mg/m³ o-cresol in the air caused nose and throat irritation.

• Oral

Ingestion of liquid products containing cresols can cause serious gastrointestinal damage and even death.

• Dermal

Application of concentrated cresols to the skin can cause severe skin damage and even death.

Laboratory animals

• Inhalation

Short-term exposure to cresols in air has caused irritation of the respiratory tract and muscle twitching.

• Oral

Placing cresols in the stomach of animals by means of a feeding tube has caused muscle twitching and loss of coordination.

Eating food contaminated mostly with p-cresol or with a mixture of m- and p-cresol for 28 days or longer has caused lesions inside the nose of rats and mice; mice also developed lesions in the lungs and in the thyroid gland.

• Dermal

Short-term application of cresols to the skin of animals has produced skin irritation.

Cancer

The EPA has determined that cresols are possible human carcinogens. The International Agency for Research on Cancer (IARC) has not classified cresols as to their carcinogenicity.

Effects in children

There are no studies of children exposed to cresols, but it is expected that children exposed to cresols will suffer the same effects observed in exposed adults.

There is a report of a baby who suffered serious damage to the skin, liver, and kidneys, went into a coma, and eventually died 4 hours after liquid cresol was accidentally spilled on his head.

Birth defects

Fetal toxicity and birth defects have been reported in animals given cresols. This generally occurred with doses that were also toxic to the mothers.

Breast milk

There is no information on levels of cresols in breast milk.

Tobacco smoke

Cresols are components of tobacco smoke. Avoid smoking in enclosed spaces like inside the home or car in order to limit exposure to children and other family members.

Consumer products

Household cleaners and disinfectants containing cresols should be stored out of the reach of young children to prevent accidental poisonings and skin burns and follow manufacturer's directions on the label.

Detecting exposure

Cresols can be measured in blood and urine. Cresols are normal constituents of human urine.

Measuring exposure

A higher-than-normal concentration of cresols in the urine may suggest recent exposure to these substances or to substances that are converted to cresols in the body.

The detection of cresol and/or its metabolites in your urine cannot be used to predict the kind of health effects that might develop from that exposure.

Drinking water

EPA has not established drinking water standards and health advisories for cresols.

Workplace air

OSHA set a legal limit of 5 parts per million (ppm) cresols (all isomers) in air averaged over an 8-hour work day.