Epidemiological analysis of the association between hearing and barium in humans

• Published in: Journal of exposure science & environmental epidemiology Vol. 26; no. 5; pp. 488 - 493
• Main Authors: Ohgami, Nobutaka, Mitsumatsu, Yuji, Ahsan, Nazmul, Akhand, Anwarul Azim, Li, Xiang, Iida, Machiko, Yajima, Ichiro, Naito, Mariko, Wakai, Kenji, Ohnuma, Shoko, Kato, Masashi
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.09.2016; Nature Publishing Group
• Subjects: 692/699/375; 692/700/1750; 692/700/478/174; 704/172/169/895; Adolescent; Adult; Analysis; Arsenic; Bangladesh; Barium; Barium - adverse effects; Barium - analysis; Barium - urine; Body Mass Index; Body size; Child; Epidemiology; Female; Hair; Hair - chemistry; Health aspects; Hearing; Hearing loss; Hearing Loss - chemically induced; Hearing protection; Hearing Tests; Humans; Logistic Models; Male; Medicine; Medicine & Public Health; Middle Aged; Nails - chemistry; original-article; Ototoxicity; Regression analysis; Risk analysis; Risk Factors; Sex Distribution; Smoking; Surveys and Questionnaires; Toenail; Young Adult; barium; hair; hearing loss; ICP-MS; ototoxicity; toenail
• ISSN: 1559-0631; 1559-064X
• DOI: 10.1038/jes.2015.62

Our previous study experimentally showed barium (Ba)-mediated hearing loss in mice. To our knowledge, however, it remains unknown whether Ba affects hearing in humans. This epidemiological study aimed at investigating ototoxicity of Ba in humans. Associations of Ba levels in hair, toenails and urine with hearing levels (1, 4, 8 and 12 kHz) were analyzed in 145 Bangladeshi subjects. Binary logistic regression analysis with adjustment for age, sex, body mass index (BMI) and smoking showed that Ba levels in hair had significant associations with hearing loss at 8 kHz (OR=4.75; 95% CI: 1.44, 17.68) and 12 kHz (OR=15.48; 95% CI: 4.04, 79.45). Ba levels in toenails were also associated with hearing loss at 8 kHz (OR=3.20; 95% CI: 1.35, 7.85) and 12 kHz (OR=3.63; 95% CI: 1.58, 8.55), whereas there was no correlation between Ba level in urinary samples and hearing. There was a significant correlation between hearing loss and Ba levels in hair and toenails in the model adjusted with arsenic levels as the confounder. In conclusion, this study suggested that Ba levels could be a new risk factor for hearing loss, especially at high frequencies of 8 and 12 kHz, in humans.