Personal Exposure to PM2.5, Black Carbon and Carbon Monoxide and Their Effects on Atherosclerosis: A Cross Sectional Assessment in Bangladesh

Abstract

About 40% of the world’s population are exposed to hazardous particles from biomass fuel use at households. Effects of such exposures on preclinical markers of cardiovascular diseases (CVD) are practically challenging to measure and mostly unexplored in low- and middle-income countries. GEOHealth study is examining the effect of individual level exposures to PM 2.5, black carbon (BC) and carbon monoxide (CO) on atherosclerosis among 600 biomass fuel users in rural Bangladesh.We are measuring PM 2.5 by gravimetric method using personal air samplers (RTI MicroPEM™). BC is being determined by reflectance measurement using an EEL-type smoke stain Reflectometer. CO is measured by Lasker EL-USB CO data logger. We assessed Carotid intima thickness (cIMT), a marker of atherosclerosis, using the SonoSite MicroMaxx ultrasound machine equipped with a L38e/10-5 MHz transducer. We are using the mean of the near and far walls of the maximum common carotid artery (CCA) IMT from both sides of the neck as the outcome variable. Structured questionnaire is used to record important co-variates.The primary analysis was conducted among 100 women (mean age 40±8 years), who has been using biomass fuel in traditional stoves for 20±9 years. They were all non-smoker with low (<5 µg/L) exposure to water arsenic and not known to have any CVD. Average 48 hour exposure to PM2.5, BC and CO was 124µg/m3 (SD 108), 4.8 µg/m3 (SD 2.1) and 1.2 ppm (SD 0.9) respectively. Mean cIMT is 740.9µm (SD 78). We will construct a multiple linear regression model and strength of association adjusted for important co-variates will be reported. We plan to complete data analysis on 200 samples by June 2018 and expect to present the finding at the ISEE meeting.Findings will help establish effects of HAP on atherosclerosis providing insights into magnitude, underlying mechanism and prevention strategies of the problem.