Blood lead (Pb) is associated with lung fibrotic changes in non-smokers living in the vicinity of petrochemical complex: a population-based study

Abstract

Abstract Background: Lead (Pb) is a toxic metal that was used in many industrial processes and it does not go away over time and remains in the environment. This makes human exposure to lead and the poisonous effects of lead may affect our organ of body. We wonder whether lead which intake from inhalation, ingestion, and skin could do harm to our respiratory system and ultimately induce lung fibrosis. Methods: This study examines the blood lead levels from each of the participants who lived more than two years in Dalinpu and older than 20 years old from 2016 to 2018 in Kaohsiung Municipal Siaogang Hospital. The blood samples were analyzed for lead levels by graphite furnace atomic absorption spectrometry. LDCT (Low-Dose computed tomography) scans were performed and were interpreted by experienced radiologists. Blood lead levels were categorized into quartiles (Q1: ≤1.10; Q2: >1.11 and ≤ 1.60; Q3: >1.61 and ≤2.30, and Q4: >2.31 µg/dL). Results: Individuals with lung fibrotic changes had significantly higher (mean ± SD) blood lead levels (1.88±1.27vs. 1.72±1.53 µg/dl, p< 0.001) than those with non-lung fibrotic changes. In multivariate analysis, we found that the highest quartile (Q4: >2.31 µg/dL) lead levels (OR: 1.35, 95% CI: 1.01-1.81; p= 0.045) and the higher quartile (Q3: >1.61 and ≤2.30 µg/dL) (OR: 1.32, 95% CI: 1.01-1.73; p= 0.045) was significantly associated with lung fibrotic changes compared with the lowest quartile (Q1: ≤1.10 µg/dL). The dose-response trend was significant (Ptrend= 0.037). Conclusions: Lead exposure was significantly associated lung fibrotic change. The blood lead level should be lower than current reference value to prevent lung toxicity.