Health risk assessment of construction workers from trace metals in PM2.5 from Kolkata, India.

Construction activities have long been recognized as a pertinent source of PM2.5 though limited information exists regarding chemical characteristics of aerosols generated during building demolition/construction. A comprehensive investigation was carried out to assess the physical (SEM analysis) and chemical (ICP MS analysis) properties of PM2.5 in a building demolition and construction site and compared with background. Average concentrations of PM2.5 at both the sites exceeded the National Ambient Air Quality Standards (NAAQS). Overall trend of the total metal concentrations of PM2.5 followed the order of (Na, Ca, Al, Mg, Fe, Zn) > (Ti, Sr, Cd, Ba, Pb, V, Cr, Mn, Co, Ni, Cu) in both the sites. Sr, Ba, Mg, Zn, Ti, Cd, Al, Cr, Fe, Co, Mn, V, Ni, Ca, and Zn showed a ∼1.3-3.0 fold increase, and Pb showed the highest increase of almost >3.5 times when compared to the background concentrations. Health risk estimates based on the bio-available concentration of metals indicated that hazard quotient (HQ) values for non-carcinogenic metals were within the prescribed limit (HQ ≤ 1). However, the excess lifetime cancer risk (ELCR) for the carcinogenic metals Pb, Ni, Cd, and Cr(VI) were higher than the guideline limits of USEPA.