In a thought-provoking inaugural address titled ‘When Breathing Is Dangerous’, Professor Janine Wichmann, a professor in the School of Health Systems and Public Health (SHSPH), Faculty of Health Sciences, University of Pretoria, delivered a compelling discourse on the profound effects of air pollution on human health, with a particular focus on its implications within South Africa.

Prof Wichmann began her address by referring to the cover page of her presentation, which featured the Tšwelopele Building at the Faculty of Health Sciences campus. The term ‘tšwelopele’ translates to ‘success or prosperity, going forward or advancement’, a fitting representation of her inaugural lecture held at the Senate Hall, University of Pretoria, on 2 October 2023.

Her primary emphasis throughout the address was on the far-reaching consequences of air pollution exposure on human health. She explained that her research primarily concentrates on studies conducted in South Africa, excluding her research outputs as a visiting researcher or postdoctoral fellow in the Netherlands, Denmark and Sweden.

Prof Wichmann's journey into the domain of air pollution's health impact began with her daily commute past the Union Buildings in Pretoria. This route exposed her to the visible signs of air pollution, sparking questions about whether others also perceived it and why, despite having air quality regulations in place for years, South Africa continued to struggle with high levels of air pollution.

"I always wonder whether other people also notice the visible air pollution. And why we see such high air pollution levels even though the country had an Air Quality Act for the past 18 years," Prof Wichmann pondered.

Air pollution disease burden equivalent to major health risks

To underscore the urgency of the issue, Prof Wichmann referred to the United Nations Sustainable Development Goals and the updated 300-page World Health Organization (WHO) Air Quality Guideline Report that was published in September 2022.

"The updated WHO Global Air Quality Guideline report concluded that air pollution health effects are observed at lower concentrations than previously recognised," Prof Wichmann shared, emphasising the critical need to address this concern.

"The disease burden linked to air pollution is now estimated to be equivalent to other major global health risks, such as unhealthy diets and tobacco smoking," Prof Wichmann stressed.

Highlighting the global scope of air pollution exposure, she noted that in 2019, over 90% of the world's population experienced annual average PM2.5 concentrations exceeding the WHO Air Quality Guideline. PM2.5 refers to air particulate matter with an aerodymanic diameter small or equal to 2.5 μ.

"In 2019, more than 90% of the world’s population experienced annual average PM2.5 concentrations that exceeded the WHO Air Quality Guideline of 5 μg/m3," Prof Wichmann pointed out, underscoring the widespread nature of the problem.

Importance of establishing Air Quality Management Plans

Within the South African context, Prof Wichmann outlined several challenges, including the lack of electronic data, insufficient air quality monitoring stations, and limited access to vital data such as mortality statistics.

"Lack of electronic data, such as government-run public hospital admission data, good quality air quality data, scarce skills to estimate exposure data from e.g., satellite data, air pollution models and data science methods etc.," she noted, shedding light on the obstacles faced in her research.

Regarding the South African context, she delved into the importance of establishing Air Quality Management Plans (AQMPs) for each province and municipality.

"The majority of countries have an Air Quality Act, so you may wonder why high air poll levels is still observed? The short answer is that Air Quality laws are not all equal, one must scrutinise their content," Prof Wichmann explained, highlighting the need for comprehensive and enforceable air quality regulations.

In her studies, she delved into understanding the exposure-response relationship between air pollution and various health outcomes. She presented results from her epidemiology research, including findings on the impact of air pollution on cardiovascular disease deaths, respiratory disease hospital admissions, and the significance of PM2.5 and black carbon (BC) (a chemical component of PM2.5) levels.

Her research encompassed seven epidemiology studies, including some from her MSc and PhD students' projects. These studies consistently reported that air pollution levels exceeded the daily and yearly WHO guideline values frequently in cities like Cape Town, Durban, Johannesburg, and especially in the highly polluted Highveld Air Pollution Priority and Vaal Triangle Air Pollution Priority areas.

Vulnerable groups often identified as being at higher risk

One notable finding was that PM10 levels in Johannesburg during 2006-2010 averaged 57 µg/m³, almost double that of Cape Town and Durban (32 µg/m³). NO2 levels were significantly higher in Johannesburg, while SO2 levels peaked in Durban. In Secunda, located in the Highveld Air Pollution Priority area, the PM10 average during 2011-2016 was 69 µg/m³, with a maximum level of nearly 500 µg/m³, exceeding the WHO daily guideline of 45 µg/m³ more than 10 times on that day.

Prof Wichmann highlighted the increased risk of respiratory and cardiovascular disease hospital admissions and mortality associated with rising air pollution levels. Vulnerable groups, including women, children and the elderly, were often identified as being at higher risk.

Prof Wichmann pointed out that addressing air pollution necessitates primary prevention initiatives, such as transitioning to clean energy sources, rehabilitating mine dumps, and establishing safe and efficient public transport systems. It is also crucial to educate parents about the harm second-hand smoke can cause to their children's health.

Her research revealed that various sources of air pollution, both indoor and outdoor, increased the risk of allergic diseases like asthma, allergic rhinitis and eczema, as well as respiratory conditions like wheezing, chronic obstructive pulmonary disease, bronchitis and adult cardiovascular disease conditions such as hypertension, arrhythmias and heart attacks. Childhood mortality was also elevated based on data from the 1998 South African Demographic and Health Survey.

Prof Wichmann's call for continued research, education, and awareness-building is a crucial step toward ensuring a healthier and cleaner future for South Africans.  As she concluded her address, Prof Wichmann called on researchers to be part of the solution and not contribute to environmental degradation. She emphasised the need for universities and individuals to embrace sustainability and environmental responsibility.