A correlation of secondary aerosol (nitrate and sulfate) with respirable particulate matter (RPM) in ambient air at different traffic junctions of Vadodara city.

The correlation study of secondary aerosol (nitrate and sulfate) with RPM in ambient air at different traffic junctions of Vadodara city is reported. RPM was analyzed using Ion Chromatography technique and measured the level of nitrate and sulfate in ambient air. The correlation studies of these particulates with RPM have been established. The average concentration of sulfate and nitrate in ambient air was found 35.74 microg/m3 and 24.22 microg/m3, which ranged of 5.33-84.69 and 1.93-77.86 microg/m3 respectively. The correlation of RPM and SO4 (r = 0.813, P<0.01), RPM-NO3 (r = 0.5549, P<0.01) and SO4-NO3 (r = 0.6133, P<0.01) were found significant. The presence of sulfate and nitrate in RPM is 8.25% and 5.60% . The pH of water extract of RPM averaged 6.81, which ranged 6.17-7.28. Regression analysis result showed that the relationship between RPM-SO4 was significantly (R2=0.66215) correlated. This indicate that probably the secondary aerosols such as nitrate and sulfate in excess may cause irritation and increasing lung disease.

Pulmonary function status of shopkeepers of Ahmedabad exposed to autoexhaust pollutants.

The study deals with evaluation of pulmonary function status (VC, FEV1% and FEF25-75%) in Ahmedabad shopkeepers stationed near different traffic junctions and relating them with the levels of oxides of nitrogen (NOx) near these junctions categorised as Heavy, Medium and Low polluted area junctions. The pulmonary function test (PFT) values of heavy polluted and medium polluted area shopkeepers is compared with low polluted area shopkeepers. The influence of smoking habits and duration of exposure over PFT values was seen. The prevalence of airway obstruction in shopkeepers was compared with USA population. The results indicated significant impairment in FEV1% and FEF25-75% value in high polluted area shopkeepers where NOx level is much higher than TLV value. In medium polluted area, where NOx level is slightly higher than TLV value, shopkeepers demonstrated significant impairment in FEF25-75%. Smoking is found to have an additive effect. A linear increase in the prevalence of pulmonary impairment with increasing duration of exposure was evidenced. Shopkeepers exhibited higher prevalence of impairment in both smokers and non-smokers than USA population attributing it to the effect of autoexhaust pollutants. This study also denoted that FEF25-75% is an early indicator of obstruction in smaller airways which is the primary site of deposition of inhaled pollutants.