Occupational Hearing Loss Surveillance
Facts and Definitions
Scope of the Problem
- In the United States, hearing loss is the third-most common chronic physical condition among adults after hypertension and arthritis.
- About 12% of the U.S. working population has hearing difficulty.
- About 24% of the hearing difficulty among U.S. workers is caused by occupational exposures.
- About 8% of the U.S. working population has tinnitus (‘ringing in the ears’) and 4% has both hearing difficulty and tinnitus.
What causes Occupational Hearing Loss (OHL)?
- OHL can occur when workers are exposed to loud noise or ototoxic chemicals.
- Noise is considered loud (hazardous) when it reaches 85 decibels or higher, or if a person has to raise his/her voice to speak with someone 3 feet away (arm’s length).
- Ototoxic chemicals can cause OHL, make the ear more susceptible to the damaging effects of hazardous noise, or both. For example, a person taking certain ototoxic pharmaceuticals may lose hearing, become more susceptible to noise, or both. Ototoxic chemicals (and examples) include:
- solvents (styrene, trichloroethylene, toluene)
- metals and compounds (mercury compounds, lead, organic tin compounds)
- asphyxiants (carbon monoxide, hydrogen cyanide)
- nitriles (3-Butenenitrile, cis-2-pentenenitrile, acrylonitrile)
- pharmaceuticals (certain antineoplastic agents)
How Many Workers are Exposed?
- About 22 million workers are exposed to hazardous noise each year.
- About 10 million workers are exposed to solvents and an unknown number are exposed to other ototoxicants.
What is OHL Surveillance?
OHL surveillance includes:
- Collecting worker hearing data, exposure data and related information for analysis;
- Estimating how many workers have hearing loss or related health outcomes and how many workers are exposed;
- Examining these estimates by industry and occupation; and
- Monitoring trends over time.
The NIOSH OHL Surveillance Project commenced to establish a national repository for OHL data, and to conduct surveillance and research of this common occupational illness.
Motivation, Description, Status
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