O-169 Longitudinal changes of oxidative and methylated DNA damage among workers handling engineered metal oxides nanoparticles. (14th March 2023)

• Record Type: Journal Article
• Authors: Su, Ting-Yao; Lai, Ching-Huang; Liou, Saou-Hsing; Wu, Wei-Te
• Is Part Of: Occupational and environmental medicine. Volume 80(2023)Supplement 1
• Page Start: A13
• Page End: A13
• Publication Date: 2023-03-14
• Subjects: Medicine, Industrial -- Periodicals; Environmental health -- Periodicals; 616.980305
• DOI: 10.1136/OEM-2023-EPICOH.32
• Languages: English
• ISSNs: 1351-0711

Abstract

Abstract : Introduction: Due to the increasing demand of engineered nanomaterials (ENMs) in industrial application, the health of engineered nanoparticle (ENPs) exposed workers is engaging more attention. Metal and metal oxide nanoparticles are often used as industrial catalysts which can generate reactive oxygen species leading to increased oxidative stress in humans after inhaling. However, more understanding is needed to clarify the physiological effects and plausible biological mechanisms associated with ENPs. This study aimed to assess long-term changes in oxidative stress and DNA methylation damage in workers exposed to metal oxides nanoparticles. Material and Methods: 376 participants from 15 factories completed a questionnaire interview, blood and urine samples donation during their annual physical examinations from 2010 to 2012. Urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) and N7-methylguanine (N7-MeG) were identified as biomarkers of oxidative and methylated DNA damage, respectively. Plasma superoxide dismutase (SOD) and glutathione peroxidase-1 (GPx-1) were identified as biomarkers of antioxidants. Based on the ENMs handled by the participants, they were divided into four groups: nano-titanium dioxide (nano-TiO2) and nano-silver (nano-Ag) co-exposed, nano-Ag exposed, nano-TiO2 exposed, and reference group. Results: After adjusting for confounders in generalized estimating equation (GEE) model, a significant increase in log N7-MeG of 112.4% (β = 0.327, 95% C.I. = 0.171 to 0.484) and a significant decrease in log GPx-1 of 6.6% (β = -0.030, 95% C.I. = -0.052 to -0.007) were found in the nano-Ag exposed group compared with the reference group. A significant decrease in log SOD of 13.4% (β = -0.062, 95% C.I. = -0.122 to -0.003) was found in the nano-TiO2 and nano-Ag co-exposed group compared with the reference group. Conclusion: Elevated methylated DNA damage and reduced enzymatic antioxidant activity were observed in workers exposed to Nano-Ag. Notably, this study also observed a reduced enzymatic antioxidant activity in the nano-TiO2 and nano-Ag co-exposed workers.