Immune cells and cardiovascular health in premenopausal women of rural India chronically exposed to biomass smoke during daily household cooking.

Changes in cells of the immune system are important indicators of systemic response of the body to air pollution. The aim of this study was to investigate the immunological changes in rural women who have been cooking exclusively with biomass for the past 5 years or more and compare the findings with women cooking exclusively with liquefied petroleum gas (LPG). We conducted a cross-sectional analysis of the associations between indices of indoor air pollution (IAP) and a set of immune assays. Biomass users illustrated marked suppression in the total number of T-helper (CD4+) cells and B (CD19+) cells while appreciable rise was documented in the number of CD8+ T-cytotoxic cells and CD16+CD56+ natural killer (NK) cells. A consistent finding among biomass users was rise in regulatory T (Treg) cells. Among biomass users, peripheral lymphocyte subpopulations, Treg cells, and the number of typical monocytes (CD16-CD64+ cells), antigen presenting types (CD16+CD64- cells) and plasmacytoid cells (CD16-CD64- cells) were found to be significantly altered in those who daily cooked with dung in comparison to wood and crop residue users (p<0.05). Biomass users who cooked in kitchens adjacent to their living areas had significant changes in peripheral lymphocyte subpopulations, typical monocytes (CD16-CD64+) with high phagocytic activity and antigen presenting monocytes (CD16+CD64-) against women who cooked in separate kitchens (p<0.01). This study has shown that women who cooked exclusively with biomass fuel had alterations in immune defense compared with their neighbors who cooked with LPG.