Associations of dermal diethyl phthalate level with changes in lung function test value mediated by absolute eosinophil count: A panel study of adults in southern Taiwan

Chih-Wen Wang; Da-Wei Wu; Szu-Chia Chen; Huang-Chi Chen; Hung-Hsun Lin; Hung Su; Jen-Taie Shiea; Wen-Yi Lin; Chih-Hsing Hung; Chao-Hung Kuo

doi:10.1016/j.envres.2020.110613

Associations of dermal diethyl phthalate level with changes in lung function test value mediated by absolute eosinophil count: A panel study of adults in southern Taiwan

Environ Res. 2021 Mar:194:110613. doi: 10.1016/j.envres.2020.110613. Epub 2020 Dec 24.

Authors

Chih-Wen Wang¹, Da-Wei Wu², Szu-Chia Chen³, Huang-Chi Chen², Hung-Hsun Lin⁴, Hung Su⁵, Jen-Taie Shiea⁶, Wen-Yi Lin⁷, Chih-Hsing Hung⁸, Chao-Hung Kuo⁹

Affiliations

¹ Division of Hepatobiliary, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Center for Cancer Research, Kaohsiung Medical University, Kaohsiung, Taiwan.
² Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
³ Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. Electronic address: scarchenone@yahoo.com.tw.
⁴ Department of Laboratory Technology, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan.
⁵ Department of Chemistry, National Sun Yat-Sen University Kaohsiung, Taiwan.
⁶ Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Chemistry, National Sun Yat-Sen University Kaohsiung, Taiwan; Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁷ Department of Occupational Medicine, Health Management Center, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung City, Taiwan.
⁸ Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Pediatrics, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. Electronic address: pedhung@gmail.com.
⁹ Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.

PMID: 33345897
DOI: 10.1016/j.envres.2020.110613

Abstract

Phthalate concentrations in indoor and outdoor dust are associated with respiratory disease. Both immunoglobulin E (IgE) and eosinophil count are associated with airway inflammation from exposure to environmental allergens. Dermal phthalate level can be used as a matrix for assessing personal exposure through direct absorption from the air, particle deposition, or contact with contaminated products. However, the association between dermal phthalate level and changes in lung function test values, as mediated by immunological response, remains unclear. In total, 237 adults in southern Taiwan were recruited. Spirometry measurements (in L) of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were taken on visits 1 (2016-2018) and 2 (2019). Dermal phthalate level, absolute eosinophil count, and IgE level were recorded on visit 1. Mean changes in FVC and FEV1 decrease pear year, as determined through pairwise comparisons, were significant (^diffFVC_{per year}: -0.46, 95% CI: -0.51, -0.41; p < 0.001; ^diffFEV1_{per year}: -0.37, 95% confidence interval [CI]: -0.41, -0.34; p < 0.001). For FEV1 decrease, log-unit increases in dermal diethyl phthalate (DEP) were positively associated with ^diffFEV1_{per year} (β = 0.096; 95% CI: 0.042, 0.150; p = 0.001) and negatively associated with absolute eosinophil count (β= -0.201; 95% CI: -0.380, -0.023; p= 0.027). Log-unit increases in absolute eosinophil count were negatively associated with ^diffFEV1_{per year} (β= -0.109; 95% CI: -0.150, -0.068; p < 0.001). Absolute eosinophil count mediated 19.70% of the association between dermal DEP level and ^diffFEV1_{per year}. For FVC decrease, log-unit increases in dermal DEP were positively associated with ^diffFVC_{per year} (β = 0.095; 95% CI: 0.035, 0.155; p = 0.002) and negatively associated with absolute eosinophil count (β = -0.243; 95% CI: -0.427, -0.060; p = 0.010). Log-unit increases in absolute eosinophil count were negatively associated with ^diffFVC_{per year} (β= -0.122; 95% CI: -0.168, -0.076; p < 0.001). Absolute eosinophil count mediated 29.98% of the association between dermal DEP level and ^diffFVC_{per year}. The results suggest that dermal DEP level is positively associated with changes in lung function test values and is mediated by absolute eosinophil count.

Keywords: Absolute eosinophil count; Dermal phthalate; Diethyl phthalate; Forced expiratory volume in 1 s; Forced vital capacity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Eosinophils*
Forced Expiratory Volume
Lung*
Phthalic Acids
Respiratory Function Tests
Taiwan
Vital Capacity

Substances

Phthalic Acids
diethyl phthalate