Review A review on the deteriorating situation of smog and its preventive measures in Pakistan Waseem Raza a , Saad Saeed b , Hammad Saulat a , Hajera Gul c , Muhammad Sarfraz a , Christian Sonne d , Z.-H. Sohn e , Richard J.C. Brown f , Ki-Hyun Kim g, * a State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology,116024, PR China b NFC Institute of Engineering & Technology, Department of Chemical Engineering, Khanewal Road Opposite Pak Arab Fertilizers, Multan, 60000, Pakistan c National Centre of Excellence in Physical Chemistry, University of Peshawar, 25120, Peshawar, Pakistan d Aarhus University, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000, Roskilde, Denmark e Department of Environmental Engineering, Dong-Eui University, Busan, 47340, Republic of Korea f Environment Department, National Physical Laboratory, Teddington, TW110LW, UK g Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul, 04763, Republic of Korea article info Article history: Received 2 May 2020 Received in revised form 1 August 2020 Accepted 9 August 2020 Available online 15 August 2020 Handling editor: Prof. Jiri Jaromir Klemes Keywords: Smog Air pollution Air quality Smog prevention Smog formation abstract Urbanization, industrialization, and increasing fossil fuel consumption are generally identified as the main contributors to poor air quality. Smog is a form of visible air pollution processes that can cause diverse health problems (e.g., pulmonary, respiratory, and skin diseases). In Lahore, the second-largest city of Pakistan, smog pollution has been a significant socioeconomic issue since 2013 of which situa- tion has been worsening each year. In this systematic review, we discuss the major issues concerning smog in Pakistan: the causes, methods of detection, hazardous effects, and opportunities for preventive measures based on ground-level information. This study identifies smog as a potential source of human health risk as serious repercussions of economic development. It is thus suggested that adequate abatement measures should be established for the proper protection of public health. © 2020 Elsevier Ltd. All rights reserved. Contents 1. Introduction ........................................................................................................................ 2 2. Types of smog and the related chemistry ............................................................................................... 2 2.1. Classical smog (London smog) .................................................................................................. 3 2.2. Photochemical smog ............................................................................................................ 4 2.3. Polish smog ................................................................................................................... 4 3. Sources of smog in Pakistan and methods of detection .................................................................................. 4 4. Hazards of smog ..................................................................................................................... 5 4.1. Effects on human health ........................................................................................................ 6 4.2. Effect on agricultural sector ..................................................................................................... 7 4.3. Effect on the economy .......................................................................................................... 8 4.4. Effects on tourism .............................................................................................................. 8 5. Smog preventive measures for Pakistan ................................................................................................ 8 5.1. Technical measures .......................................................... .................................................. 9 5.1.1. Transportation .......................................................................................................... 9 5.1.2. Domestic ............................................................................................................. 10 * Corresponding author. E-mail address: kkim61@hanyang.ac.kr (K.-H. Kim). Contents lists available at ScienceDirect Journal of Cleaner Production journal homepage: www.elsevier.com/locate/jclepro https://doi.org/10.1016/j.jclepro.2020.123676 0959-6526/© 2020 Elsevier Ltd. All rights reserved. Journal of Cleaner Production 279 (2021) 123676