IMPACT OF AIR POLLUTION ON RESPIRATORY SYMPTOMS AND LUNG FUNCTION IN CHILDREN LIVING IN INDUSTRIAL ZONES OF LAHORE: A CROSS-SECTIONAL ENVIRONMENTAL HEALTH STUDY

Abstract

BACKGROUND: Air pollution has become a major environmental health threat in Pakistan, particularly in Lahore’s industrialized zones where children are chronically exposed to high pollutant levels. Industrial emissions containing particulate matter (PM₂.₅, PM₁₀), nitrogen dioxide (NO₂), and sulfur dioxide (SO₂) have been linked to respiratory morbidity and impaired lung development in children, yet limited local evidence exists integrating environmental exposure with clinical lung function data.

OBJECTIVE: To assess the impact of industrial air pollution on respiratory symptoms and lung function among school-aged children living in industrial zones of Lahore through environmental exposure mapping and spirometric evaluation.

 METHODOLOGY: A cross-sectional study was conducted from March to November 2023 among 400 children aged 6–14 years (200 from industrial areas and 200 from control areas). Ambient air pollutants were monitored using portable air quality monitors, and geographic mapping was performed to estimate exposure gradients. Respiratory symptoms were assessed via standardized questionnaires, while lung function was measured using calibrated spirometry, recording FVC, FEV₁, FEV₁/FVC ratio, and PEF. Statistical analyses included t-tests, chi-square tests, and multivariate linear regression, with significance set at p<0.05.

 RESULTS: Mean PM₂.₅ levels were significantly higher in industrial zones (85.6 ± 19.4 µg/m³) compared to control areas (46.7 ± 13.2 µg/m³, p<0.001). Children from industrial areas showed higher prevalence of chronic cough (31%), wheezing (27%), and allergic rhinitis (34%). Spirometry revealed reduced FVC (1.62 ± 0.41 L vs 1.89 ± 0.38 L, p<0.001) and FEV₁ (1.38 ± 0.36 L vs 1.67 ± 0.33 L, p<0.001). PM₂.₅ concentration was inversely correlated with FEV₁ (r = –0.41, p<0.001).

CONCLUSION: Industrial air pollution in Lahore is associated with significant respiratory symptoms and measurable declines in lung function among children. Urgent air quality regulation and child-centered health monitoring are needed to prevent long-term respiratory consequences.

 KEY TERMS: Air Pollution; Child Health; Environmental Exposure; Industrial Emissions; Lahore; Lung Function Tests; Particulate Matter