The association of bone and blood manganese with motor function in Chinese workers

• Type of Material: Article
• Authors: Danelle Rolle-McFarland, Purdue University; Yingzi Liu, Emory University; Farshad Mostafaei, Purdue University; Elizabeth S Zauber, Indiana University; Yuanzhong Zhou, Zunyi Medical University; Yan Li, Zunyi Medical University; Quiyan Fan, Zunyi Med & Pharmaceut Coll; Wei Zheng, Purdue University; Linda H Nie, Purdue University; Ellen M Wells, Purdue University
• Language: English
• Date: 2022-01-01
• Publisher: ELSEVIER
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2021 Elsevier B.V. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.neuro.2021.12.005
• Title of Journal or Parent Work: NEUROTOXICOLOGY
• Volume: 88
• Start Page: 224
• End Page: 230
• Grant/Funding Information: This work was supported by the Natural Science Foundation of Guizhou Provincial Scientific and Technology Department Grant [2017-1215 (Li)]; the International Scientific and Technology cooperation project of Guizhou Province [G2014-7012 (Li and Zheng)]; the Innovative Talent Team Training Project of Zunyi City [2015-42 (Li)]; the National Natural Science Foundation of China 81860568 (Fan); the U.S. Centers for Disease Control and Prevention/NIOSH R21-OH010700 (Nie) and T03-OH008615 (Wells)]; and the U.S. NIH/National Institute of Environmental Health Sciences grants R01-ES027078 (Zheng).
• Keywords: Toxicology; Pharmacology & Pharmacy; IVNAA; TEST-RETEST RELIABILITY; QUANTIFY MANGANESE; NEUROMOTOR FUNCTION; BIOMARKERS; Biomarkers; Metal workers; SYSTEM; HEALTH; Life Sciences & Biomedicine; WELDERS; motor skills; DIAGNOSIS; Science & Technology; Movement disorders; OCCUPATIONAL-EXPOSURE; LEAD-EXPOSURE; Neurosciences; Neurosciences & Neurology; Manganese

Abstract

Manganese (Mn) is an essential element. However, Mn overexposure is associated with motor dysfunction. This cross-sectional study assessed the association between bone Mn (BnMn) and whole blood Mn (BMn) with motor function in 59 Chinese workers. BnMn and BMn were measured using a transportable in vivo neutron activation analysis system and inductively coupled plasma mass spectrometry, respectively. Motor function (manual coordination, postural sway, postural hand tremor, and fine motor function) was assessed using the Coordination Ability Test System (CATSYS) and the Purdue Pegboard. Relationships between Mn biomarkers and motor test scores were analyzed with linear regression models adjusted for age, education, current employment, and current alcohol consumption. BMn was significantly inversely associated with hand tremor intensity (dominant hand (β=-0.04, 95 % confidence interval (CI):-0.07, -0.01; non-dominant hand β=-0.05, 95 % CI:-0.08, -0.01) hand tremor center frequency (non-dominant hand β=-1.61, 95 % CI:-3.03, -0.19) and positively associated with the Purdue Pegboard Assembly Score (β = 4.58, 95 % CI:1.08, 8.07). BnMn was significantly inversely associated with finger-tapping performance (non-dominant hand β=-0.02, 95 % CI:-0.04,-0.004), mean sway (eyes closed and foam β=-0.68, 95 % CI:-1.31,-0.04), and positively associated with hand tremor center frequency (dominant hand, β = 0.40, 95 % CI:0.002, 0.80). These results suggest BMn is related to better postural hand tremor and fine motor control and BnMn is related to worse motor coordination and postural hand tremor but better (i.e., less) postural sway. The unexpected positive results might be explained by choice of biomarker or confounding by work-related motor activities. Larger, longitudinal studies in this area are recommended.