Priyanka Prasad, Bidisha Mukherjee, Hirak Saha and Dona Sinha*
Background: Groundwater arsenic (As) contamination is an alarming public health concern in West Bengal, India.
Methods: The effect of chronic low dose (11-50 μg/L) As ingestion on airway cells has been investigated in 605 never-smoking women (mean age 40 yr) in Nadia and North 24-Parganas district of West Bengal. Another 512 age-matched neversmoking women from control areas (As<10 μg/L) of these districts were enrolled as control. Cytology of spontaneously expectorated sputum was done following Pap staining, elastase enzyme in sputum cells was localized cyto chemically, and iron-laden macrophages (siderophages) were detected after Perl’s Prussian blue staining. Plasma levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8) and C-reactive protein (CRP) were measured by ELISA.
Results: Groundwater (As) was 28.3 ± 13.51 μg/L in exposed and 2.72 ± 1.18 μg/L in control areas. Sputa of As-exposed women were 42% more cellular and contained significantly increased (p<0.001) numbers of neutrophils, eosinophils, lymphocytes and alveolar macrophages (AM) than control. In addition, they showed goblet cell hyperplasia, mucus hypersecretion, and sputum cell atypia such as multinucleated cells, and metaplasia of airway epithelial cells. As-exposure was associated with abundance of siderophages, excess production of elastase in sputum neutrophils and AM, and elevated plasma levels of TNF-α, IL-6, IL-8 and CRP (p<0.001).The observed changes were positively associated with As levels in ground water after controlling age, body mass index, education, occupation and family income as potential confounders.
Conclusion: Chronic exposure to even low level As (11-50 μg/L) may cause airway inflammation and sputum cytological alterations which in the long run may provoke respiratory diseases including lung cancer.
