Ambient Air Quality Evaluation: A Comparative Study in China and Pakistan

Vehicle and industrial emissions are responsible for a considerable share of urban air pollution concentrations. We conducted a comparative study in Dalian, China and Faisalabad, Pakistan to reevaluate NO 2 , SO 2 , and CO concentrations. Our study was conducted over the course of one year at different stations in both cities, and measured values were compared with ambient air quality standards such as NEQS-Pakistan, NAAQS-USEPA, CNAAQS-China, and global standard WHO. The NO 2 concentrations in Faisalabad varied from 185-262 g/m 3 , whereas it was in the range of 44-133 g/m 3 in Dalian. The SO 2 concentration was found in the range of 66-190 g/m 3 and 56-128 g/m 3 , while CO varied from 5.4-22.3 mg/m 3 and 0.3-2.8 mg/m 3 , respectively, in Faisalabad and Dalian. The annual average NO 2 , SO 2 , and CO concentrations were below the permissible limits in Dalian; however, the measured values were considerably higher in Faisalabad. Our results are the first to compare air quality of two countries at different stations and highlight the possibility of reducing air pollution by comparing conditions.