Size distribution and lung-deposition of ambient particulate matter oxidative potential: A contrast between dithiothreitol and ascorbic acid assays

Lord Famiyeh; Chunrong Jia; Ke Chen; Yu-Ting Tang; Dongsheng Ji; Jun He; Qingjun Guo

doi:10.1016/j.envpol.2023.122437

Size distribution and lung-deposition of ambient particulate matter oxidative potential: A contrast between dithiothreitol and ascorbic acid assays

Environ Pollut. 2023 Nov 1:336:122437. doi: 10.1016/j.envpol.2023.122437. Epub 2023 Aug 25.

Authors

Lord Famiyeh¹, Chunrong Jia², Ke Chen³, Yu-Ting Tang⁴, Dongsheng Ji⁵, Jun He⁶, Qingjun Guo⁷

Affiliations

¹ Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China.
² School of Public Health, University of Memphis, Memphis, TN, 38152, USA.
³ Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China.
⁴ School of Geographical Sciences, University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China.
⁵ State Kay Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
⁶ Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China; Nottingham Ningbo China Beacon of Excellence Research and Innovation Institute, Ningbo 315100, China. Electronic address: Jun.He@nottingham.edu.cn.
⁷ Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

PMID: 37634565
DOI: 10.1016/j.envpol.2023.122437

Abstract

Particulate matter (PM) inhaled into human lungs causes oxidative stress and adverse health effects through antioxidant depletion (oxidative potential, OP). However, there is limited knowledge regarding the association between the lung-deposited dose (LDD) of PM and OP in extrathoracic (ET), tracheobronchial (TB), and pulmonary (P) regions of human lungs. Dithiothreitol (DTT) and ascorbic acid (AA) assays were employed to measure the OP of PM size fractions to investigate OP distribution in human lungs and identify the chemical drivers. Quasi-ultrafine particles (quasi-UFP, ≤0.49 μm) exhibited high OP deposition in the TB and P regions, while coarse particles (CP, ≥3.0 μm) dominated in the ET region. A plot of extrinsic (per air volume) and intrinsic (per PM mass) OP versus LDD revealed that the OP for fine and coarse particles was greatest in the ET region, whereas the OP of quasi-UFP was greatest in alveoli. The study also demonstrated that extrinsic OP and PM doses are not strongly related. The decline in OP with increasing PM dose reveals the need for further investigation of the antagonistic effects of the chemical compositions. Overall, the results presented herein help address the gap in knowledge regarding the association between the OP and LDD of ambient particles in specific regions of human lungs.

Keywords: Ascorbic acid; Dithiothreitol; Lung-deposition; MPPD; Oxidative potential; Particulate matter; Size distribution.