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

Abstract

Lead (Pb) is a toxic metal that has been extensively used in various industrial processes, and it persists in the environment, posing a continuous risk of exposure to humans. This study investigated blood lead levels in participants aged 20 years and older, who resided in Dalinpu for more than two years between 2016 to 2018, at Kaohsiung Municipal Siaogang Hospital. Graphite furnace atomic absorption spectrometry was used to analyze the blood samples for lead levels, and the LDCT (Low-Dose computed tomography) scans were interpreted by experienced radiologists. The blood lead levels were divided into quartiles, with Q1 representing levels of ≤1.10 μg/dL, Q2 representing levels of >1.11 and ≤1.60 μg/dL, Q3 representing levels of >1.61 and ≤2.30 μg/dL, and Q4 representing levels of >2.31 μg/dL. 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: 1.36, 95% CI: 1.01-1.82; p= 0.043) and the higher quartile (Q3: >1.61 and ≤2.30 μg/dL) (OR: 1.33, 95% CI: 1.01-1.75; p= 0.041) was significantly associated with lung fibrotic changes compared with the lowest quartile (Q1: ≤1.10 μg/dL) (Cox and Snell R², 6.1 %; Nagelkerke R², 8.5 %). The dose-response trend was significant (P_trend= 0.030). Blood lead exposure was significantly associated lung fibrotic change. To prevent lung toxicity, it is recommended to maintain blood lead levels lower than the current reference value.

Keywords: Blood lead; Low-dose computed tomography; Lung fibrotic changes; Petrochemical complex.