Impact assessment of Beirut explosion on local and regional air quality

On 4th August 2020, drastic explosions occurred at the port of Beirut, Lebanon. These explosions released an extensive amount of toxic gases and caused atmospheric damages along with terrestrial and marine disturbances. In the current study, the impact of the incident on both local and regional air quality was assessed by ALOHA and HYSPLIT models. The ALOHA results estimated the concentrations of NO2 and NO and their exposure times for two specific densely populated locations in the high-risk zone. The concentrations of outdoor NO2 exceeded the AEGL-3 tier in Borj Hammoud, and Jdeideh after 8, and 10 min of the explosion, respectively. The HYSPLIT results showed the movement of NOx cloud eastwards, reaching Syria, and turned southwards, affecting Iraq, Jordon, Saudi Arabia, Kuwait, Iran, and then moved to central Asia through Turkmenistan. The air quality station at Khorramabad, Iran, could observe a small peak during the NOx toxic cloud arrival time on 6th August 2020 at 13:00 UTC. Besides the Mediterranean Sea, the Caspian Sea, the Persian Gulf, and the Gulf of Oman were also affected by the toxic clouds. Damascus is in the high impacted zone with around 105 kg NO2 deposition. Fragile marine environments are also disturbed. The Persian Gulf, with more than 80% of its area, under low impacted zone was receiving 10 µgm−2. Results drag the attention to the associated risk of old factories to the environment. Therefore, it is necessary to have regular safety monitoring in industrial zones and neighboring to eliminate future incidents.