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CAS No. 7803-51-2

Phosphine (PH₃) is a colorless, flammable, and explosive gas at room temperature that smells like garlic or decaying fish.  Exposure to phosphine may cause, nausea, vomiting, stomach pain, diarrhea, thirst, muscle pain, difficulty breathing, and fluid in the lungs. Higher exposures and long-term exposure may cause serious harm. Workers may be harmed from exposure to phosphine. The level of exposure depends upon the dose, duration, and work being done.

Phosphine is used in many industries. It’s used to kill insects and rodents in stored grain and tobacco. Some examples of workers at risk of being exposed to phosphine include the following:

  • Factory workers that make electronics
  • Workers in plants that make rat poison
  • Pest control workers who use it to control for rats

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses phosphine, 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 phosphine. Useful search terms for phosphine include “hydrogen phosphide,” “phosphorated hydrogen,” “phosphorus hydride,” and “phosphorus trihydride.”

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