Environmental exposure to lead and cadmium and hearing loss in Chinese adults: A case-control study

• Published in: PloS one Vol. 15; no. 5; p. e0233165
• Main Authors: Wang, Da-Hui, Xu, Hui, Zheng, Yi-Hua, Gu, Dong-Sheng, Zhu, Ya-Jun, Ren, Ying, Wang, Shi-Chang, Yang, Lei, Xu, Liang-Wen
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 20.05.2020; Public Library of Science (PLoS)
• Subjects: Adults; Alcohol; Alcohol use; Anemia; Atomic absorption analysis; Background noise; Biology and Life Sciences; Blood; Blood levels; Cadmium; Cadmium content; Causes of; Chronic diseases; Chronic illnesses; Demographics; Demography; Diabetes; Diseases; Ear diseases; Ears & hearing; EDTA; Environmental aspects; Environmental toxicology; Epidemiology; Exposure; Health aspects; Hearing; Hearing loss; Hearing protection; Heavy metals; Hypertension; Lead (Metal); Male identity; Marital status; Medical schools; Medicine and Health Sciences; Metals (Materials); Migraine; Noise; Noise pollution; Physical Sciences; Population; Population studies; Quality of life; Questionnaires; Risk analysis; Risk factors; Social Sciences; Spectral analysis; Studies; China; Beijing China; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0233165

Hearing loss is the second most common nonfatal problem affecting the Chinese population. Historical studies have suggested an association between exposure to heavy metals, such as cadmium and lead, and hearing loss. Few studies have investigated this relationship in the general population in China. We conducted a case-control study with 1008 pairs of participants from a cross-sectional epidemiological survey conducted in Zhejiang Province. A self-designed questionnaire was adopted to collect information on demographics, chronic diseases, lifestyles and environmental noise. Pure-tone averages of hearing thresholds at frequencies of 0.5, 1, 2, and 4 kHz were computed. Blood lead and cadmium levels were analyzed with an atomic absorption spectrometer. After adjusting for all other potential confounding factors, compared with the lowest blood cadmium quartile (0.00-0.53 μg/L), blood cadmium quartile 2 (0.54-0.92 μg/L), quartile 3 (0.93-1.62 μg/L) and quartile 4 (1.63-57.81 μg/L) exhibited significantly elevated risks for hearing loss, with odds ratios of 1.932 (95% CI: 1.356-2.751), 2.036 (95% CI: 1.423-2.914) and 1.495 (95% CI: 1.048-2.133), respectively (P-trend<0.001). However, an association of lead with hearing loss was not found. Young age (less than 60 years), male sex and current smoking were associated with increased blood cadmium concentration. Additionally, a positive association between blood cadmium and lead concentrations was found. Therefore, we conclude that exposure to environmental cadmium may be a risk factor for hearing loss among the general population in China.