Occupational hearing loss is common across a wide range of industries. Most often, the damage is caused by excessive exposure to noise. But hearing loss can also be caused by exposure to chemicals referred to as “ototoxic chemicals.”
Contact with skin, inhalation, and ingestion are all possible exposure routes.
There are five general categories of ototoxic chemicals:
- Pharmaceuticals such as antibiotics (i.e., streptomycin, tetracycline)
- Solvents such as toluene and xylene
- Asphyxiants such as carbon monoxide and tobacco smoke
- Nitriles such as acrylonitrile
- Metal compounds such as mercury and lead.
Hearing loss can come from damage to different parts of the ear depending on the chemical. Some chemicals damage nerve fibers, causing hearing and balance problems. Others damage cochlear hair cells to cause hearing loss. Still others damage different hair cells leading to spatial disorientation and balance problems.
Where Exposure Can Occur
Industries where exposure to ototoxic chemicals can occur include agriculture, construction, mining, and utilities.
Occupations where exposure to both ototoxic chemicals and noise are common include:
- Pesticide spraying.
OSHA Requirements for Protecting Against Hearing Loss
The Occupational Safety and Health Administration (OSHA) sets exposure limits to known hazards and requires employers to take precautions to prevent their employees from being overexposed. If an employer cannot reduce the noise level to acceptable levels, they must provide ear plugs or muffs, training on their use, and hearing tests.
OSHA also requires employers to make safety data sheets on chemicals available to workers, in order to inform them of the dangers. Although OSHA has a long-standing standard for exposure to noise, below which hearing loss is not expected to occur, there are no such standards for the combined effect of ototoxic chemicals combined with noise.
Unfortunately, little information is available on safe levels of ototoxic chemical exposure. In addition, it has been found that combined exposure to ototoxic chemicals with noise has a synergistic effect – and can cause more hearing damage than exposure to either one alone.
Impact on Hearing
Hearing damage from exposure to ototoxic chemicals can affect hearing sensitivity, result in a standard threshold shift (loss of 10 decibels compared to a normal baseline for frequencies at 2,000, 3,000 and 4,000 hertz), or both. The damage can be temporary or permanent.
If nerve damage happens as a result of exposure to ototoxic chemicals, then not only do sounds need to be louder to be detected, they also need to be clearer. The latter type of damage involves “speech discrimination dysfunction,” where the ability to distinguish voices separately from background noise is impaired. This can involve:
- Sound distortion
- Inability to tell difference between two sounds having similar frequencies
- Inability to detect time gaps between sounds
- Inability to localize sounds
This type of impairment can make working in noisy environments difficult. It can also increase the risk of workplace injuries due to an inability to hear co-workers and warning signals.
Hearing loss can also impair activities of daily life, including appreciating music, conversations with friends and loved ones, or being able to drive safely.
Delaware Workers’ Compensation Lawyers at McCann Dillon Jaffe & Lamb, LLC Represent Workers with Hearing Loss Issues
If you have experienced hearing loss and work with chemicals and/or noise, you may be entitled to recover for damages from your employer. Call McCann Dillon Jaffe & Lamb, LLC at 302-888-1221 or contact us online to arrange for a free consultation. Our experienced Delaware Workers’ Compensation lawyers can evaluate your case and advise you on how to proceed. From our offices in Wilmington and Philadelphia we represent injured workers in Delaware, Pennsylvania and New Jersey.