A Korean study has found that high cadmium levels in the body are associated with increased hearing thresholds and hearing loss among the Korean adult population.
The study used the data from the 2010–2012 Korean National Health and Nutrition Examination Survey (KNHANES). 3,228 participants were included in the study. The participants were divided into quartiles based on their blood cadmium levels: first quartile (1Q), second quartile (2Q), third quartile (3Q), and fourth quartile (4Q) groups. All the groups had 807 participants. The hearing thresholds were measured using an automatic audiometer at 0.5, 1, 2, 3, 4, and 6 kHz. Hearing loss was defined as higher than 25 dB average hearing threshold.
The participants in the 4Q group had a higher frequency of low-to-mid frequency hearing loss, high-frequency hearing loss and average hearing threshold than those in the other groups. The participants in the 4Q group exhibited 1.59-, 1.38-, and 1.41-fold higher odds for hearing loss than those in the 1Q, 2Q, and 3Q groups of low-to-mid frequency hearing loss, high-frequency hearing loss and average hearing threshold, respectively.
Cadmium is a silver-white metal that is found in the earth's crust. It is extracted during the production of metals such as copper, lead and zinc. Cadmium is found in some foods and is emitted by using fossil fuels such as coal and oil, smoking cigarettes and burning waste.
The study, “Association between cadmium exposure and hearing impairment: a population-based study in Korean adults”, was published in Yeungnam University Journal of Medicine.
Source: Yeungnam University Journal of Medicine.