Exposure to air pollution (both outdoor and indoor) is a leading cause of 5.5 million premature deaths annually according to the Global Burden of Disease1.
An air pollutant of concern for human health is fine particulate matter (PM). In Africa, recent estimates show that the total annual deaths from ambient PM pollution increased by 36% from 1990 to 2013 (from an estimated 180,000 deaths in 1990 to 250,000 deaths in 2013). Similarly, the annual deaths from Household Air Pollution from solid fuels increased by 18% (from 400,000 to 450,000) over the same period2.
Kenya’s capital, Nairobi, is known to frequently exceed the World Health Organization’s (WHO's) 24-hour guideline value for Particulate Matter of less than 2.5 µm (PM2.5). In Nairobi’s informal settlements, where 60% of the population live, sources of outdoor air pollution are mainly dust, human and animal emissions, open burning of waste, transport and local industry, while high levels of indoor air pollution are attributed to use of traditional energy sources for cooking and heating.
The 2030 Agenda for Sustainable Development offers an opportunity to tackle air pollution, because improving air quality is essential for achieving the Sustainable development Goals (SDGs). This particularly relates to the goals for inclusive, sustainable and resilient development enabling communities to have good health and well-being (SDG No. 3) and sustainable clean energy (SDG No. 7). In 2014 the United Nations Environment Assembly (UNEA) adopted a resolution for air quality (AQ), which encouraged governments to set standards and policies across multiple sectors in order to manage the negative impacts of air pollution.
PM is composed of many different chemicals. The chemical species composition of poor AQ needs to be analysed in order to target mitigation. For example, ammonia (NH3), emitted from human and animal effluent, is an important contributor to secondary PM in European climates3. However, the importance of ammonia as an AQ driver in other climates, such as Sub-Saharan Africa, is poorly understood.