ToxFAQsTM for HMX
Spanish: HMX
CAS#: 2691-41-0 
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This fact sheet answers the most frequently asked health questions about HMX.    For more information, you may call the ATSDR Information Center at 1-888-422-8737.  This fact sheet is one in a series of summaries about hazardous substances and their health effects.  It is important you understand this information 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.
         
            
Highlights
HMX is an explosive. People who work at facilities that make HMX may be exposed to it. In one human study, no adverse effects were reported in workers exposed to unknown concentrations of HMX. Animal studies indicate that HMX may be harmful to the liver and central nervous system if it is swallowed or gets on the skin. HMX has been found in at least 10 of the 1,416 National Priorities List sites identified by the Environmental Protection Agency (EPA).
                    
What is HMX?
                 HMX is an acronym for High Melting 
                   eXplosive. It is also known as octogen and cyclotetramethylene-tetranitramine, 
                   as well as by other names. It is a colorless solid that dissolves 
                   slightly in water. Only a small amount of HMX will evaporate 
                   into the air; however, it can occur in air attached to suspended 
                   particles or dust. The taste and smell of HMX are not known.
HMX does not occur naturally in the environment. 
                   It is made from other chemicals known as hexamine, ammonium 
                   nitrate, nitric acid, and acetic acid. HMX explodes violently 
                   at high temperatures. Because of this property, HMX is used 
                   in various kinds of explosives, rocket fuels, and burster 
                   chargers. A small amount of HMX is also formed in making cyclotrimethylene-trinitramine 
                   (RDX), another explosive similar in structure to HMX.
What happens to HMX when it enters the environment?
                    
                    
                    - Most of the HMX that entered the environment was released 
                      into waste water from places that made or used HMX.
- A small amount of HMX can be released to the air as dust 
                      or ash from facilities that burn waste contaminated with 
                      HMX.
- Some HMX may be released to soil as a result of accidental 
                      spills, the settling of HMX-containing dust particles from 
                      the air, or the disposal of waste that contains HMX in landfills.
- Dust particles containing HMX may be carried by the wind 
                      for some distance.
- In surface water, HMX does not evaporate or bind to sediments 
                      to any large extent. Sunlight breaks down most of the HMX 
                      in surface water into other compounds, usually in a matter 
                      of days to weeks.
- HMX is likely to move from soil into groundwater, particularly 
                      in sandy soils.
- It is not known if plants, fish, or animals living in 
                      contaminated areas build up levels of HMX in their tissues.
How might I be exposed to HMX?
     There is no information on how often you might be exposed to HMX in the environment or to how much. Most people, however, probably won't be exposed to HMX from the environment.
People who work at facilities that make or use HMX or RDX may be exposed to HMX. These workers may be exposed by inhaling dusts that contain HMX or by getting HMX-containing liquids on their skin.  
People who live near facilities that make or use HMX, or near hazardous waste sites that contain HMX may also be exposed if a release occurs. For these residents, exposure (if any) is most likely to occur from contaminated groundwater. 
How can HMX affect my health?
                 Information on the adverse health effects 
                   of HMX is limited. In one human study, no adverse effects 
                   were reported in workers who breathed HMX. However, the concentrations 
                   of HMX in the workplace air were not reported in this study, 
                   and only a small number of workers and effects were investigated.
Studies in rats, mice, and rabbits indicate 
                   that HMX may be harmful to your liver and central nervous 
                   system if it is swallowed or gets on your skin. It is not 
                   known if HMX can affect the ability to have children, or if 
                   it can cause birth defects.
How likely is HMX to cause cancer?
                  There is no information available as 
                    to whether or not HMX can cause cancer in animals or people. 
                    The Environmental Protection Agency (EPA) has determined that 
                  HMX is not classifiable as to its human carcinogenicity.
 Is there a medical test to show whether I've been exposed to HMX?
                 You can find out if you have been exposed 
                   to HMX by having your blood, urine, or feces tested for HMX. 
                   Since HMX is poorly absorbed after it is swallowed, the levels 
                   of HMX in your blood and urine are likely to be lower than 
                   those in your feces. For best results, tests for HMX should 
                   be done within a few days after you are exposed.
These tests cannot tell you how much 
                   HMX you have been exposed to or predict whether or not you 
                   will have any health effects. This test isn't available at 
                   most doctors' offices, but can be done at special laboratories 
                   that have the right equipment.
Has the federal government made recommendations to protect human health?
                 The EPA recommends that the concentration 
                   of HMX in an adult's drinking water be less than 0.4 milligrams 
                   per liter (0.4 mg/L) for a lifetime. EPA regulates waste containing 
                   HMX as hazardous and has set restrictions on its disposal 
                   in landfills.
                 The Department of State regulates the 
                   exportation of HMX, and the Department of Transportation (DOT) 
                   regulates its transportation.
The Bureau of Alcohol, Tobacco, and Firearms 
                   (ATF) regulates the importation, manufacture, distribution, 
                   and storage of HMX.
Glossary
                 Carcinogenicity: Ability to cause cancer.
                 CAS: Chemical Abstracts Service.
                 Dissolve: To disappear gradually.
Evaporate: To change into a vapor or 
                   a gas.
References
                  Agency for Toxic Substances and Disease 
                    Registry (ATSDR). 1997. Toxicological Profile for HMX. Atlanta, GA: U.S. Department of Health 
                  and Human Services, Public Health Service.
Where can I get more information?
If you have questions or concerns, please contact your community or state health or environmental quality department or:
 
For more information, contact:
Agency for Toxic Substances and Disease Registry 
Office of Innovation and Analytics, Toxicology Section
4770 Buford Highway
Chamblee, GA 30341-3717
Phone: 1-800-CDC-INFO  888-232-6348 (TTY) 
Email: Contact CDC-INFO
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.