Assessment of
PM2.5 bound Heavy Metals and Associated Health impact- A case study in Warangal
City, India
Selvetikar Ashok and Matli Chandra Sekhar
Res. J. Chem. Environ; Vol. 27(5); 27-41;
doi: https://doi.org/10.25303/2705rjce027041; (2023)
Abstract
PM2.5 in the atmosphere is widely reported, but few studies have focussed on the
metal-bound particle concentration of PM2.5 in urban areas. The present study aims
to quantify Heavy Metals (HM) concentration associated with PM2.5 for the urban
region of Warangal in the State of Telangana, India. A Respirable Dust sampler was
used to collect the air samples during the study period and the samples were analysed
for specific heavy metals [Iron (Fe), Zinc (Zn), Nickel (Ni), Cadmium (Cd) and Copper
(Cu)] using Microwave Plasma Atomic Emission Spectroscopy (MP-AES). Average PM2.5
values were found to be above the annual limit (40 μg/m3) set by the National Ambient
Air Quality Standard (NAQS) of India and range from 41.58 to 58.21 μg/m3for the
region studied. Slightly higher concentrations of Zn and Fe were observed as compared
to Cu, Ni and Cd. The order of heavy metal based on the concentration levels was
as follows: Zn>Fe>Cu>Ni>Cd (higher to lower concentration). Analysis of enrichment
factor showed that the Zn, Cu and Cd fall in the highly enriched element category.
Based on health risk assessment for intake pathways, the risk of exposure was found
to be in the following order: Ingestion>Dermal>Inhalation. Non-carcinogenic and
carcinogenic risks for children and adults were found to be negligible. Source identification
studies based on Concentration Weighted Trajectory (CWT), Potential Source Contribution
Function (PSCF) and cluster analysis results showed that the western and north-western
regions of India are more dominant contributors. Furthermore, cluster 4 was reported
to have high significance (27.11%) and dominant contributions of trajectories were
observed from the regions of Maharashtra, Chhattisgarh, Rajasthan and Madhya Pradesh.
The results of the study can help policy makers implement mitigation measures and
formulate suitable regulations to reduce the health risk associated with PM2.5 and
heavy metals in the atmosphere.
