AMBIENT AEROSOL INDUCED CARDIOVASCULAR DISEASE AMONG SUBJECTS IN MONSOON AND WINTER SEASON

Background: Air pollution is being increasingly linked to cardiovascular diseases (CVD) worldwide. This present study compares the potential of ambient aerosol in inducing CVD among security guards at IIT Delhi campus during two contrasting seasons, namely Monsoon (least polluted) & Winter (most polluted). Methods: A novel methodology for case crossover sampling has been developed for this health study. Both personal and ambient exposure of aerosol has been studied. Healthy and susceptible subjects (security guards) were recruited using a detailed health questionnaire. 6-8 Hours ECG (Electrocardiogram) of subjects was obtained using holter system and activity chart with a data generation frequency of 1 minute interval along with health parameters like blood pressure, Saturation of Peripheral Oxygen (SpO₂), pulse, Body Mass Index (BMI), etc. Ambient and personal air monitoring was done for number and mass concentrations using GRIMM Mini-WRAS 1371 (Wide Range Aerosol Spectrometer), OPC (Optical Particle Counter), 4-stage Sioutas personal cascade impactor and PM_2.5 sampler simultaneous to ECG. The Mini-WRAS readings were obtained at 1 minute intervals to match ECG data for the exact same durations. The same subjects were repeated 2-3 times each season to get consistency in results and removal of any ambiguity in ECG data. The subjects that were identified as potentially susceptible by questionnaire and first round of health monitoring data were repeated more frequently and followed closely. The ECG data was correlated with aerosol concentration in consultation with a cardiologist to identify for CVD. Results: Monsoon season had the lesser aerosol concentration and its effects in inducing CVD were less as was evident by arrhythmia patterns of ECG reports. Winter season had a higher aerosol concentration and a corresponding high relative risk in inducing CVD. Conclusions: The variation in CVD potential due to aerosol varies seasonally. More number of such studies in case crossover mode for longer durations are required to be done to further validate the results and help in minimizing such effects by restricting exposure in high risk seasons and during high ambient aerosol concentrations.