No abstract

No abstract

Ambient air pollution is emerging environmental problem in major cities of Pakistan. Service sector growth is 8% and there is a rapid development of infrastructure in cities especially in transport sector which causes ambient air pollution issues in mega cities. To estimate the level of pollution in the city of Lahore, ambient air quality mapping procedure was used with the help of Haz Scanner HIM-6000 equipped with different sensors and ArcGIS 10.3 software was used for mapping of these pollutants. This study continued for two months from September to October, 2017 for different pollutants like PM2.5, VOCs, Ozone, NOx, CO2, CO, SO2 and H2S. From the study, it was concluded that ambient air in Lahore has lot of pollutants especially PM2.5, NO, NO2, CO, SO2 where as conc. of VOCs, H2S and Ozone was in limits in relation to NEQs for these pollutants.

This study was conducted to estimate the contribution of vehicular exhaust gases towards ambient air quality in Lahore, Pakistan during 2017. LANDCOM-III flue gas analyzer was used for determination of vehicular exhaust pollutants (CO, SO2, NO2, NO, H2S, HC) for five vehicles groups (motor bikes, Qingqi rickshaw, local cars, imported cars and public transport vans) from April to September, 2017. Major pollutants were compared with their National Environmental Quality Standards (NEQS) for the country. Ambient air quality was monitored using Haz scanner HIM-6000 during smog formation in the city in October and November, 2017. From the study, it was concluded that except local and imported cars, all vehicles groups emit high concentration of pollutants as compared to the standard values. It is also observed that public transport vehicles i.e. Qingqi rickshaw and vans contribute more towards atmospheric pollution as compared to other vehicle groups in the city. During smog formation in the city, PM2.5 and PM10, NO, NO2 (NOx) concentration was decreased whereas concentration of O3, H2S and VOCs increased in November than October. Ozone concentration during the smog was below NEQS indicating that smog was not totally photochemical smog but mainly originated from vehicular and industrial exhaust gases.

Punjab is the leading province of Pakistan in the production of bovine milk and its consumption. Rapid industrialization, high energy demand and production of waste have increased the risk of PCB toxicity in the environment. This research work was designed to assess human dietary exposure of polychlorinated biphenyls (∑PCBs17 congeners) through ingestion of buffalo and cow's milk from eight main districts of Punjab, Pakistan. The average concentration of ∑DL-PCBs (8.74 ng g -1 and 14.60 ng g -1 ) and ∑I-PCBs (11.54 ng g -1 and 18.68 ng g -1 ) in buffalo and cow milk samples were analyzed respectively. The PCB 156 was predominantly high congener found in both buffalo (2.84 ng g -1 ) and cow milk (2.86 ng g -1 ). It was found that the highest PCBs in bovine milk samples were observed in close vicinities of urban and industrial areas. The estimated daily consumptions of DL-PCBs and I-PCBs, from buffalo and cow milk, were below the acceptable daily intake for both adults and children. Moreover, Hazard Quotients (HQ) of ∑PCBs17 congeners value were less than 1.0 in adults and greater in the case of children reflecting the high chances of cancer risk. Furthermore, comprehensive monitoring for childhood cancer is recommended to establish the relationship in future studies.