__________________________________________________________________________________________ 

 

 

______________________________________ 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

This Public Health Statement is the summary 

chapter from the Toxicological Profile for nHexane. It is one in a series of Public Health 

Statements about hazardous substances and their 

health effects. A shorter version, the ToxFAQsTM, is 

also available. This information is important 

because this substance may harm you. The effects 

of exposure to any hazardous substance depend on 

the dose, the duration, how you are exposed, 

personal traits and habits, and whether other 

chemicals are present. For more information, call 

the ATSDR Information Center at 1-888-422-8737. 

This public health statement tells you about nhexane and the effects of exposure. 

The Environmental Protection Agency (EPA) 

identifies the most serious hazardous waste sites in 

the nation. These sites make up the National 

Priorities List (NPL) and are the sites targeted for 

long-term federal cleanup activities. n-Hexane has 

been found in at least 60 of the 1,467 current or 

former NPL sites. However, the total number of 

NPL sites evaluated for this substance is not known. 

As more sites are evaluated, the sites at which nhexane is found may increase. This information is 

important because exposure to this substance may 

harm you and because these sites may be sources of 

exposure. 

When a substance is released from a large area, 

such as an industrial plant, or from a container, such 

as a drum or bottle, it enters the environment. This 

release does not always lead to exposure. You are 

exposed to a substance only when you come in 

contact with it. You may be exposed by breathing, 

eating, or drinking the substance or by skin contact. 

If you are exposed to n-hexane, many factors 

determine whether you'll be harmed. These factors 

include the dose (how much), the duration (how 

long), and how you come in contact with it. You 

must also consider the other chemicals you're 

exposed to and your age, sex, diet, family traits, 

lifestyle, and state of health. 

1.1 WHAT IS n-HEXANE? 

n-Hexane is a chemical made from crude oil. Pure 

n-hexane is a colorless liquid with a slightly 

disagreeable odor. It evaporates very easily into the 

air and dissolves only slightly in water. n-Hexane is 

highly flammable, and its vapors can be explosive. 

Pure n-hexane is used in laboratories. Most of the 

n-hexane used in industry is mixed with similar 

chemicals in products known as solvents. Common 

names for some of these solvents are "commercial 

hexane," "mixed hexanes," "petroleum ether," and 

"petroleum naphtha." An older name for these 

types of solvents is "petroleum benzine." Several 

hundred million pounds of n-hexane are produced 

in the United States each year in the form of these 

solvents. The major use for solvents containing nhexane is to extract vegetable oils from crops such 

as soybeans. They are also used as cleaning agents 

in the printing, textile, furniture, and shoemaking 

industries. Certain kinds of special glues used in 

the roofing and the shoe and leather industries also 

contain n-hexane. Several consumer products 

contain n-hexane. For example, gasoline contains 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

about 1–3% n-hexane. n-Hexane is also present in 

rubber cement. 

1.2 WHAT HAPPENS TO n-HEXANE WHEN 

IT ENTERS THE ENVIRONMENT? 

n-Hexane enters the air, water, and soil during its 

manufacture and use. Wastes containing n-hexane 

are sometimes disposed of in landfills. n-Hexane 

can enter the environment from these landfills. nHexane also enters the environment from accidental 

spills during transport and leaks from storage 

containers. 

n-Hexane evaporates very easily into the air. Once 

in the air, n-hexane can react with oxygen and be 

broken down. n-Hexane released into the air is 

broken down in a few days. 

If n-hexane is spilled into a lake or river, a very 

small portion will dissolve in the water, but most 

will float on the surface. The n-hexane will then 

evaporate into the air. The n-hexane dissolved in 

the water can be broken down by certain types of 

bacteria, although it is not known how long this 

takes. 

If n-hexane is spilled on the ground, much of it will 

evaporate into the air before it penetrates the soil. 

Any n-hexane that penetrated the soil would 

probably be broken down by bacteria. If n-hexane 

leaks from an underground storage tank, it will float 

on the groundwater, rather than mixing with it since 

n-hexane is lighter than water. 

n-Hexane is not stored or concentrated by plants, 

fish, or animals. 

1.3 HOW MIGHT I BE EXPOSED TO nHEXANE? 

Since gasoline contains n-hexane, almost everyone 

is exposed to small amounts of n-hexane in the air. 

The n-hexane in gasoline is released into the air at 

service stations and in automobile exhaust. Some 

people may also be exposed by spilling gasoline on 

their skin. The concentration of n-hexane in the air 

in Chicago was recently measured and contained 2 

parts n-hexane per 1 billion parts air (2 ppb). nHexane has generally not been found in most foods 

or drinking water, so you are not likely to be 

exposed by eating or drinking. Because cooking 

oils are processed with solvents containing nhexane, very small amounts may be present in these 

products. However, the amounts in cooking oil are 

too low to have any effect on people. 

People living near hazardous waste sites containing 

n-hexane or near its manufacturing, processing, or 

storage facilities could potentially be exposed. 

Because of the chemical properties of n-hexane, the 

most likely way a person would be exposed is by 

breathing in air contaminated with n-hexane. A less 

likely way for a person to be exposed is by drinking 

contaminated private well water. 

You may be exposed to n-hexane if you use 

products containing it at work. This exposure will 

mainly be by breathing in air containing n-hexane, 

but you can also be exposed through your skin by 

contact with substances containing n-hexane. Some 

occupational groups that may be exposed to nhexane include refinery workers, shoe and footwear 

assembly workers, laboratory technicians, workers 

operating or repairing typesetting and printing 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

machinery, construction workers, carpet layers, 

carpenters, auto mechanics and gas station 

employees, workers in plants manufacturing tires or 

inner tubes, and workers in air transport and air 

freight operations. Exposure can also occur in the 

home if products containing n-hexane are used 

without proper ventilation. 

1.4 HOW CAN n-HEXANE ENTER AND 

LEAVE MY BODY? 

n-Hexane can enter your body through your lungs if 

it is in the air you breathe. It can also enter your 

body through your stomach and intestines if it is in 

your drinking water or food, or through your skin if 

you come into contact with it. How much n-hexane 

enters your body depends on how long you are 

exposed and the amount to which you are exposed. 

Once you inhale n-hexane, it goes into your 

bloodstream and is carried to all the organs in your 

body. Enzymes in your liver break down n-hexane. 

If you are exposed to high concentrations of nhexane over a long period, one of these breakdown 

products may cause damage to your nervous 

system. Most of these breakdown products leave 

your body in the urine within a day or two. nHexane and its breakdown products are not stored 

in your body. 

1.5 HOW CAN n-HEXANE AFFECT MY 

HEALTH? 

Almost all the people known to have had their 

health affected by exposure to n-hexane used it at 

work. In the 1960s and early 1970s, several 

outbreaks of nerve disorders occurred among shoe 

workers in Japan and Italy. Doctors determined the 

disease was caused by the workers breathing air 

containing high concentrations of n-hexane. The nhexane came from glues and solvents the workers 

used in assembling the shoes. In one group of 

workers in Japan, it was estimated that the workers 

who became ill had been breathing air containing 

500–2,500 parts n-hexane per million parts air 

(500–2,500 ppm) for 8–14 hours a day for 6 months 

to several years. The first symptom that the 

affected workers had was a feeling of numbness in 

their feet and hands. This was followed by muscle 

weakness in the feet and lower legs. If exposure 

continued, the symptoms grew worse. In some 

workers, paralysis of the arms and legs developed. 

When the affected workers were examined by 

doctors, the nerves controlling the muscles in their 

arms and legs were found to be damaged. The 

medical term for this condition is "peripheral 

neuropathy" (peripheral means outside the brain and 

spinal cord; neuropathy means nerve damage). 

Fortunately, once the workers were removed from 

exposure to n-hexane they recovered within 6 

months to a year, although some of the more 

severely affected did not fully recover for 1–2 

years. 

Poor ventilation of the work area was a major factor 

in all of these cases. Workers who became ill 

usually worked in their homes or in very small 

workshops. Since the 1970s, workplace ventilation 

has been improved and levels of n-hexane in the air 

have been lower. There have been very few cases 

of nerve damage from n-hexane since 1980. A few 

people have also suffered nerve damage from 

"sniffing" products containing n-hexane. Like cases 

in the workplace, the number of cases due to 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

sniffing has fallen since the 1970s. 

It is not known if oral or skin exposure to n-hexane 

can cause these effects in people. There have been 

very few documented exposures to n-hexane by 

these routes in people. 

To protect the public from the harmful effects of 

toxic chemicals and to find ways to treat people 

who have been harmed, scientists use many tests. 

One way to see if a chemical will hurt people is to 

learn how the chemical is absorbed, used, and 

released by the body; for some chemicals, animal 

testing may be necessary. Animal testing may also 

be used to identify health effects such as cancer or 

birth defects. Without laboratory animals, scientists 

would lose a basic method to get information 

needed to make wise decisions to protect public 

health. Scientists have the responsibility to treat 

research animals with care and compassion. Laws 

today protect the welfare of research animals, and 

scientists must comply with strict animal care 

guidelines. 

When rats are exposed to n-hexane in the air, they 

show signs of damage to their nervous systems very 

similar to those seen in people who became ill after 

workplace exposure. As in people, these effects in 

rats depend on the concentrations of n-hexane in air 

and how long exposure lasts. Studies in rats 

showed that a breakdown product of n-hexane 

(called 2,5-hexanedione) causes the nerve damage, 

not n-hexane itself. Testing for 2,5-hexanedione in 

the urine can be used to determine if a person has 

been exposed to potentially harmful amounts of nhexane. Studies in rats also showed that n-hexane 

can cause nerve damage when given orally in very 

large doses. 

At very high levels of n-hexane in air (1,000– 

10,000 ppm), signs of damage to sperm-forming 

cells in male rats occurred. Damage to the lungs 

occurred in rabbits and mice. People have rarely 

been exposed to these high levels of n-hexane, so it 

is not known if these effects would occur in people. 

It is not known if exposure to n-hexane can affect 

fertility in people. Experiments done with animals 

that were fed or breathed in n-hexane did not show 

any effect on fertility. 

There is no evidence that exposure to n-hexane 

increases the risk of cancer in people. No reliable 

information is available on whether n-hexane causes 

cancer in animals. In an animal experiment with 

commercial hexane (which contains n-hexane), an 

increase in liver cancer was found in female mice 

after exposure for 2 years. No increase was found in 

male mice or in rats of either sex. Commercial 

hexane is a mixture, and we do not know what parts 

of the mixture caused the cancer in the female mice. 

n-Hexane has not been characterized for 

carcinogenicity by the Department of Health and 

Human Services (DHHS), the International Agency 

for Research on Cancer (IARC), or the 

Environmental Protection Agency (EPA). 

1.6 HOW CAN n-HEXANE AFFECT 

CHILDREN? 

This section discusses potential health effects from 

exposures during the period from conception to 

maturity at 18 years of age in humans. Potential 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

effects on children resulting from exposures of the 

parents are also considered. 

Harmful effects from exposure to n-hexane have 

mainly occurred in adults. This is because most 

known cases have occurred in workers. However, it 

is probable that if children were exposed to nhexane at levels that cause harmful effects in adults, 

similar effects would occur. We do not know 

whether children differ from adults in their 

susceptibility to health effects from n-hexane 

exposure. Only a few animal studies have 

compared the effects of n-hexane between adults 

and young animals. In these studies, the young 

animals were somewhat less likely to have harmful 

effects on their nervous system from breathing nhexane than the adults, but more likely to die from a 

large oral dose. 

Experiments in rats and mice have shown little 

effect of n-hexane exposure on the development of 

the fetus. It is probable that n-hexane and its 

breakdown products can cross the placenta and also 

be excreted in breast milk, but no accurate 

measurements have been made in people. n-Hexane 

and its breakdown products have been detected in 

the fetus when pregnant rats were exposed to nhexane. 

1.7 HOW CAN FAMILIES REDUCE THE 

RISK OF EXPOSURE TO N-HEXANE? 

If your doctor finds that you have been exposed to 

significant amounts of n-hexane, ask whether your 

children might also be exposed. Your doctor might 

need to ask your state public health department to 

investigate. 

Certain products used in the home may contain nhexane, for example, some quick-drying glues and 

cements used in hobbies. These products should be 

kept out of the reach of children and only used with 

proper ventilation. Always store household 

chemicals in their original, labeled containers. 

Never store household chemicals in containers 

children would find attractive to eat or drink from, 

such as old soda bottles. Keep your Poison Control 

Center's number by the phone. 

Sometimes older children sniff household chemicals 

in an attempt to get "high." Your children may be 

exposed to n-hexane by inhaling products 

containing it. Talk with your children about the 

dangers of sniffing chemicals. Sniffing products 

containing n-hexane has caused paralysis of the 

arms and legs in teenagers in the United States and 

Europe. 

1.8 IS THERE A MEDICAL TEST TO 

DETERMINE WHETHER I HAVE BEEN 

EXPOSED TO N-HEXANE? 

If you have been exposed to harmful amounts of nhexane, the amount of one of its breakdown 

products (2,5-hexanedione) will probably be 

increased in your urine. Your doctor will have to 

send a sample to a specialized laboratory. This test 

can only detect n-hexane exposure occurring within 

2–3 days before the test, since 2,5-hexanedione 

leaves the body within a few days after exposure. 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

1.9 WHAT RECOMMENDATIONS HAS THE 

FEDERAL GOVERNMENT MADE TO 

PROTECT HUMAN HEALTH? 

The federal government develops regulations and 

recommendations to protect public health. 

Regulations can be enforced by law. Federal 

agencies that develop regulations for toxic 

substances include the Environmental Protection 

Agency (EPA), the Occupational Safety and Health 

Administration (OSHA), and the Food and Drug 

Administration (FDA). Recommendations provide 

valuable guidelines to protect public health but 

cannot be enforced by law. Federal organizations 

that develop recommendations for toxic substances 

include the Agency for Toxic Substances and 

Disease Registry (ATSDR) and the National 

Institute for Occupational Safety and Health 

(NIOSH). 

Regulations and recommendations can be expressed 

in not-to-exceed levels in air, water, soil, or food 

that are usually based on levels that affect animals; 

then they are adjusted to help protect people. 

Sometimes these not-to-exceed levels differ among 

federal organizations because of different exposure 

times (an 8-hour workday or a 24-hour day), the use 

of different animal studies, or other factors. 

Recommendations and regulations are also 

periodically updated as more information becomes 

available. For the most current information, check 

with the federal agency or organization that 

provides it. Some regulations and 

recommendations for n-hexane include the 

following: 

OSHA has set a Permissible Exposure Limit (PEL) 

of 500 ppm for n-hexane in workplace air. A court 

decision struck down a proposed PEL of 50 ppm. 

Damage to nerves has been found in people at 500 

ppm. The American Conference of Governmental 

Industrial Hygienists (ACGIH) recommends a 

Threshold Limit Value (TLV) of 50 ppm. 

1.10 WHERE CAN I GET MORE 

INFORMATION? 

If you have any more questions or concerns, please 

contact your community or state health or 

environmental quality department or: 

Agency for Toxic Substances and Disease Registry 

Division of Toxicology 

1600 Clifton Road NE, Mailstop F-32 

Atlanta, GA 30333 

Information line and technical assistance: 

Phone: 888-422-8737 

FAX: (770)-488-4178 

ATSDR can also tell you the location of 

occupational and environmental health clinics. 

These clinics specialize in recognizing, evaluating, 

and treating illnesses resulting from exposure to 

hazardous substances. 

To order toxicological profiles, contact: 

National Technical Information Service 

5285 Port Royal Road 

Springfield, VA 22161 

Phone: 800-553-6847 or 703-605-6000 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 
 

 

 

 

__________________________________________________________________________________________ 

 

 

PUBLIC HEALTH STATEMENT 

n-HEXANE 

CAS#: 110-54-3 

Division of Toxicology July 1999 

Reference 

Agency for Toxic Substances and Disease Registry 

(ATSDR). 1999. Toxicological profile for n-hexane. 

Atlanta, GA: U.S. Department of Health and 

Human Services, Public Health Service. 

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service
 

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov