In the past 5 years, several studies and advances have
improved understanding of the causes and factors
affecting susceptibility to noise-induced hearing loss.
Noise-induced hearing loss is widely accepted to be a
symptom of a complex disease that results from the
interaction of genetic and environmental factors.
Heritability might explain up to 50% of hearing loss
variability in individuals after exposure to noise, but
definitive studies are needed. Identification of susceptibility
genes might help to identify the population at high
risk and improve targeted hearing protection in predisposed
individuals. Much progress has been made in
the understanding of molecular mechanisms involved in
hair-cell and nerve damage. Recent research from investigators
using stem cells to recover the damaged sensory
circuits in the cochlea is at a very early stage, but could
lead to potential therapeutic strategies.33 Attention is
increasing on the risks of combined exposure to high-level