Spatial Heterogeneity in Health Risk Assessment of Heavy Metals During North-East Monsoon and South-West Monsoon over India

The present study reports the health risk assessment in heavy metals (Cr, Cd, Pb, As, Mn, and Ni) in particulate matter (< 2.5 µm) measured at 18 different sites of five climatic zones India during the distinct seasons namely the northeast monsoon (NEM) and the southwest monsoon (SWM) in campaign mode for the period of 2014–2019. The concentration of these heavy metals in PM_2.5 was determined using WD-X-ray fluorescence (XRF). Health risk assessment of heavy metals was performed estimating Hazard quotient (HQ) and carcinogenic risk (CR) assessment for adults and children for the heavy metals. HI < 1 implies no health hazard, and HI > 1 indicates that adverse health impacts may occur. Exposure to harmful toxic metals for adults and children, the total excess cancer risk higher than the threshold range (10^–4–10^–6) of heavy metals is considered significant. Since airmass movement during the two seasons (NEM and SWM) is completely different, a variation is expected in the concentration of heavy metals and associated health risk factors. During NEM the CR for children (2–4 × 10^–6) is more observed at several sites namely Patiala, Lucknow, Varanasi, Bhuvneshwar, Jaisalmer, and Rajkot, whereas, for adults, the moderate CR (1–9 × 10^–6) is at sites Darjeeling, Jorhat, Giridh, Delhi, Udaipur, Jaisalmer, and Bikaner. CR value for children and adults is comparatively lower during SWM than NEM.