by Neil Bauman, Ph.D.

 In December of 2006 I wrote about smoking and hearing loss and pointed out that smoking in the presence of loud noise makes your ears even more susceptible to hearing loss than either smoking or loud noise alone.

Now, researchers have published the results of a study on workers in one manufacturing plant showing just how severely noise combined with smoking can affect hearing loss. Here are the shocking results. Workers who were exposed to noise above 85 dB and who smoked had an incidence of significant hearing loss 442% greater than those who worked in the same noisy environment but didn’t smoke.

The researchers next compared the incidence of workers who had hearing loss greater than 30 dB between 4000 Hz and 10,000 Hz in both ears. The incidence of hearing loss was only 11.2% in non-smokers, but was a whopping 49.5% in smokers.

When looking at these same workers, but just considering hearing loss greater than 25 dB at 4,000 Hz in their better ear, the results were even more pronounced. Non-smokers had an incidence of hearing loss of 18.4%, but that figure sky-rocketed to 63.6% in smokers.1

Therefore, if you value your hearing, you need to do two things. First, if you smoke, stop smoking. Second, wear ear protectors when around noise louder than about 80 dB for extended periods.

Note: smoking isn’t the only agent that has this synergistic effect when combined with loud noise. A number of drugs, chemicals (particularly the organic solvents) and heavy metals also have this property. “Ototoxic Drugs Exposed” (chapters 8 and 14) explains this in much more detail and lists the specific drugs, chemicals and heavy metals that have this nasty property.

1 Extracted from “Interaction of smoking and occupational noise exposure on hearing loss: a cross-sectional study” Gholamreza Pouryaghoub, et. al. Dept of Occupational Medicine, Tehran University of Medical Sciences, Tehran, Iran published in BMC Public Health 2007, 7:137. http://www.biomedcentral.com/1471-2458/7/137.