Safety Training - Hearing loss from chemicals

Noise is the workplace hazard normally associated with occupational hearing loss. But health and safety researchers are giving increased attention to a lesser-known threat to normal hearing – ototoxins.

Industrial Hygiene News reports that ototoxins are chemicals that can damage the auditory nerve and cochlear hair cells in the inner ear, with routes of exposure through inhalation, ingestion, and skin absorption. When ototoxic chemicals enter the bloodstream, they can be circulated to the ear and lead to mild hearing loss or profound deafness.

The work activities where noise and ototoxins combine include painting, printing, construction, manufacturing of metal, leather, and petroleum products and fueling vehicles and aircraft.

The following control strategies have been recommended by various U.S. agencies:

* Perform task-based assessments of individual worker exposure to ototoxic chemicals using personal air sampling devices and/or skin and surface samplers.
* Take steps to reduce potential ototoxin exposures through inhalation, ingestion, or skin absorption.
* Conduct yearly audiograms for workers exposed to ototoxins when Airborne and dermal exposure levels are high.

For more information on the combined effects of chemicals and noise, see the NIOSH Topic Page at NIOSH.