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CAS No. 123-91-1

1,4-Dioxane (CHO) is a colorless liquid or solid at cool temperatures (below 53°F). It can harm the eyes, skin, lungs, liver, and kidneys. 1,4-Dioxane may cause cancer. Workers may be harmed from exposure to 1,4-dioxane. The level of exposure depends upon the dose, duration, and work being done.

1,4-Dioxane is used in many industries. It is used as an industrial solvent, a laboratory reagent, and in the manufacture of other chemicals. Some examples of workers at risk of being exposed to 1,4-dioxane include the following:

  • Employees working in scientific laboratories
  • Workers exposed to certain types of industrial solvents
  • Factory workers involved in producing some cosmetics
  • Workers in paper pulping industries

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses 1,4-dioxane, please read chemical labels and the accompanying Safety Data Sheets for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.

The following resources provide information about occupational exposure to 1,4-dioxane. Useful search terms for 1,4-dioxane include “diethylene dioxide,” “diethylene ether,” “dioxane,” “1,4-dioxane,” and “p-dioxane.”

NIOSH Chemical Resources

Related NIOSH Resources

  • NIOSHTIC-2 search results on 1,4-dioxane—NIOSHTIC-2 is a searchable database of worker safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.
  • NIOSH Worker Health Study Summaries—NIOSH conducts research to prevent illnesses and injuries in the workplace. The NIOSH Worker Notification Program notifies workers and other stakeholders about the findings of these research studies.

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