Paper Title
Impact of Corona Virus Stay-At-Home Policies on Traffic Emissions and Ambient Pollutant Concentrations in Ghana, West Africa

Abstract
The objective of this study was to determine how policies for stay-at-home (lockdown) and phases of easing the lockdown, implemented by Ghana to slow the spread of COVID-19, impacted traffic emissions and ambient concentrations of particulate matter (PM10, PM2.5). For January 2020 to June 2020, mean monthly data were obtained from four roadside monitoring locations using MiniVol Air Samplers. High-volume ambient samplers were used to collect PM data at two permanent (industrial and residential) locations. Graphs of mean monthly concentrations were plotted versus time over the six-month period. Results showed that PM2.5 concentrations decreased over Greater Accra in the month of April during the initial lockdown, when only essential workers went to work, and increased thereafter. PM2.5 concentrations were lowered by 45.5%, 46.7%, 82.4%, 72.7% at Kaneshie First Light, Shangri-la, Tantra Hill and Amasaman roadside monitoring locations respectively, compared with 2019 data. This was consistent with measured reductions in mobility during the lock-down. PM10 concentrations for the same four roadside monitoring locations, however, were higher during the lockdown compared to data for the same period in 2019; PM10 concentrations at the industrial monitoring site near the electric power plant were also higher. This increase may have been due to residential biomass burning during stay-at-home orders, or increased electricity production to support home activity. Keywords - Corona Virus, Tactical Air Sampler, Traffic Emissions, Particulate Matter, Stay-at-home Policies, Ghana