Seasonal Variation of Selected Metals in Particulate Matter at an Industrial City Kota, India

Manju Meena,Ashu Rani,Bharat Singh Meena,Uttra Chandrawat

doi:10.4209/aaqr.2015.02.0074

Abstract

This study investigates seasonal variation in concentration of some heavy metals in suspended and respirable particulate matter (SPM and RPM) collected from five different zones situated in Kota city during both summer (March, April, May and October) and winter (January, February, November and December) seasons of 2011–2012. Mean concentrations of anthropogenic origin metals (Pb, Zn, Cu and Cd) were higher in winter and lower in summer with their relative abundance in order: Zn ＞ Pb ＞ Cu ＞ Cd while reverse trend was observed for crustal origin metals (Ca, Mg and Fe) at all zones. Meteorological conditions such as temperature, relative humidity, wind velocity and wind direction during winter and summer were found affecting the metals concentration trends in different seasons. Wind roses indicate that the zones lying in predominant North-east wind direction from point source (KSTPS) in winter (25.74%) and summer (15.31%) faced higher metal burden following zone 1, which is suffering most owing to its closest location to the source. Statistical analysis by Pearson’s correlations, enrichment factor and principal component analysis indicates that coal based Thermal Power Plant is the major source of heavy metals besides other industrial activities in the study area. It is to be noted that because of higher residence time, significant concentration of Pb is found at all the zones in the city which, probably, has its origin in earlier vehicular exhaust as well.

Highlights

Particulate matter (PM) in the atmosphere is a complex mixture of elemental and organic carbon, mineral dust, trace elements and water (Lim et al, 2010)
This study investigates seasonal variation in concentration of some heavy metals in suspended and respirable particulate matter (SPM and RPM) collected from five different zones situated in Kota city during both summer (March, April, May and October) and winter (January, February, November and December) seasons of 2011–2012
The monitoring of particulate matter levels in atmosphere is important as finer particles are related to stronger health effects it is necessary to quantify the metal content adsorbed onto these particles and identify their main sources

Summary

INTRODUCTION

Particulate matter (PM) in the atmosphere is a complex mixture of elemental and organic carbon, mineral dust, trace elements and water (Lim et al, 2010). The present study has been conducted during both summer (March, April, May and October) and winter (January, February, November and December) seasons of 2011–2012 with the main objectives: i) to determine the composition of suspended and respirable particulate matter in terms of crustal (Fe, Ca and Mg) and anthropogenic (Cu, Cd, Zn and Pb) metals at various sampling sites located in five different zones covering entire Kota city area; ii) to identify possible sources of heavy metals associated with SPM and RPM using statistics namely enrichment factor, Pearson’s correlation coefficient and principal component analysis; iii) to study the effect of climate on the concentration levels of heavy metals as a function of sampling sites, distance from KSTPS, seasons and meteorological parameters such as temperature, relative humidity, wind speed and wind direction

BACKGROUND

MATERIALS AND METHODS

AND DISCUSSION

Findings

CONCLUSION