Ambient air pollution and health in Accra, Ghana

Overview

Accra is a city that has experienced rapid growth in the last decades. According to the last available census, in 2010, the total population of the Greater Accra Metropolitan Area (GAMA) was approximately 4 million, including 1.85 million in the city of Accra, and projections indicate an increase up to 6.3 million and almost 3 million, respectively, by 2030.

The levels of air pollution are affected by seasonal variation, and in particular, during the dry season, there are high peaks due to desert dust. Nevertheless, throughout the year, anthropogenic sources of air pollution are responsible for keeping average values high and for serious health impacts. Data on air pollution are available from different sources, including official monitoring stations and satellites. For the health risk assessment, values collected and modelled reveal:

• for the city of Accra: PM_2.5 average concentration levels equal to 49.5 μg/m³, from residential monitoring stations in 2014–2015; and

• for the whole Greater Accra region: PM_2.5 average equal to 36.0 μg/m3, from satellite data from 2014 and 2015.

These levels of air pollution are a burden on the health of the population. In the report, different scenarios are modelled and explored to reduce current PM_2.5 levels to reach WHO Air quality guidelines and interim targets. The estimates of the impacts of air pollution, for example potentially prevented yearly mortality is approximately 1790 deaths if WHO AQG is reached, provide significant arguments for implementing policies that reduce air pollution emissions in Accra.