Spacing out: Air pollution and human health

Professor Janine Wichmann is an environmental epidemiologist and Head of the Environmental and Occupational Sciences Division, School of Health Systems and Public Health, at the University of Pretoria.

“My research interest is investigating human health effects due to air pollution and climate change indicators, and I am the local principal investigator of the epidemiology research for the global Multi-Angle Imager for Aerosols (MAIA) project of the National Aeronautics and Space Administration (NASA),” said Prof Wichmann.

“The MAIA project represents the first time NASA has partnered with epidemiologists and health organisations to use space-based data to study human health and improve lives. Numerous study sites around the world are included, but only South Africa, Ghana, Kenya and Ethiopia in Africa,” she said.

According to Prof Wichmann, “The MAIA satellite is due to be launched by NASA in 2022 and the main aim of the global project is to see what the human health effects are of fine particulate matter of a diameter of 2.5mm, known as PM2.5, and its chemical composition.

“The satellite will orbit Earth for two years until 2024 and along with local MSc or PhD students I’ll see if there’s a link between the levels of the PM2.5 chemical species and various types of deaths or hospital admissions, such as those associated with respiratory disease, in the Johannesburg/Pretoria area between 2022 and 2024,” said Prof Wichmann. “Various local researchers based at the Council for Scientific and Industrial Research, the University of Johannesburg, North-West University, the South African Earth Observation Network, the University of the Witwatersrand and the South African Weather Service will be involved in the local air pollution exposure assessment and modelling part of the project.”

The MAIA project was announced by NASA in 2016 as part of its Earth Venture programme. The project was envisioned because, generally, measuring the air quality in specific places has been done by having expensive equipment in a fixed place which measured air particles in the locality. However, these monitoring networks are few and far between, especially in densely populated and highly polluted areas.

Prof Wichmann explains that, “Particulate matter in the air includes many chemical species that may be toxic and the degree to which they contribute to human health effects, such as respiratory disease, also varies. This requires us to know what specific air pollutants, combination of pollutants, sources of pollutants, and characteristics of pollutants are most responsible for our ill health such as adverse birth conditions, cardiovascular and respiratory disease, and premature death.

“Studies have shown that maternal exposure to severe air pollution is associated with adverse birth outcomes, such as restricted intrauterine growth, preterm delivery, and low birthweight; short-term exposure on a daily to monthly basis is associated with respiratory illness, such as asthma and premature death; and chronic exposure over many years is associated with cardiovascular and respiratory disease,” said Prof Wichmann.

According to NASA, the MAIA satellite will generate comprehensive information on particle size distribution, shape, and light-scattering and absorption for a set of globally distributed target areas. MAIA’s novelty is to include all of these capabilities at moderately high spatial resolution. The MAIA cameras will be mounted on a 2-axis gimbal that provides multiple-angle views.

“By understanding what’s in the air we breathe, and just how toxic it may be, we can make decisions for establishing global standards for our air quality and for discovering strategies to control air pollution in a targeted approach,” says Prof Wichmann.

In 1999, NASA’s Terra satellite showed a possible solution for providing global estimates of PM2.5 exposure levels by measuring aerosol optical depth (a measure of particle light extinction in the atmosphere). Now, satellite-based methods have been developed to estimate ground-level PM2.5 levels to support local monitoring and help fill the gaps in data for a better understanding of the link between air pollution and respiratory and other diseases. MAIA’s algorithm will be able to work out the total particles present in the air, including chemical composition such as sulphate, nitrate, organic carbon and black carbon.

Click on the video in the sidebar to learn more about the quality of Pretoria's air or click on the infographic in the sidebar to learn more about respiratory disease.

Talking Point: Prof Wichmann and Dr Olutola have also found that respiratory issues worsen on warmer days.

Researchers

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  Professor Janine Wichmann

  Professor Janine Wichmann is an associate professor at the School of Health Systems and Public Health (SHSPH), Faculty of Health Sciences, University of Pretoria. She is an environmental epidemiologist with a primary interest in air pollution exposure assessment and health effects. Since 2008, she has focused on climate change health effects, and mainly the short-term heat effects on and mortality and morbidity. She gained research and teaching experience in Europe from 2002 to 2012. Prof Wichmann has been a visiting researcher at the University of Gothenburg, Sweden, since 2013.
  
  She has lectured in various postgraduate (master's and PhD level) courses at the SHSPH for the past 18 years. She has also lectured in various postgraduate (master's and PhD level) courses at the University of Copenhagen during 2009-2012. She is the PhD coordinator at the SHSPH.
  
  She is committed to knowledge sharing and education which is evident in my postgraduate supervision track record at UP and other local as well as international universities.
  
  Prof Wichmann’s long-term research objective is to estimate the burden of non-communicable disease due to air pollution and climate change indicators whilst training postgraduate students in these skills. Her research addresses the evidence gaps in air quality management plans as required by the National Environmental Management Act: Air Quality Act (2005) in South Africa.
  
  In 2016, she received a prestigious Fulbright Research Visiting Scholarship. Since 2017, professor Wichmann has been the local principal investigator for short-term epidemiology studies of the Multi-Angle Imager for Aerosols (MAIA) project of the National Aeronautics and Space Administration (NASA). This is the first time NASA has entered into a partnership with epidemiologists and health organisations using space-based data to study human health and improve lives.
  
  

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  Dr Bukola Olutola

  Dr Bukola Olutola did her undergraduate studies at the University of Ibadan in Nigeria and has been doing research at the University of Pretoria (UP) for the past 10 years. She says UP provides the ideal atmosphere for researchers. “We have access to journal articles through the library, and there are many research workshops to help both upcoming and established researchers to improve their research.”
  
  Dr Olutola is a lecturer in public health at IIE MSA, formerly Monash South Africa, and an Extraordinary Lecturer at UP’s School of Health Systems and Public Health. Her research into air pollution contributes to the betterment of the world because, according to the World Health Organisation, pollution is the highest environmental cause of disease and premature death. Ambient (outdoor) and household air pollution causes seven million premature deaths annually, which amounts to 16% of global mortality. “Studies on pollution are relevant to find ways to prevent deaths arising from pollution,” says Dr Olutola.
  
  A recent highlight for her was the publication of her findings of the modifying effect of temperature on the association between air pollution and hospital admission for respiratory disease in one of South Africa’s air pollution priority areas.
  
  Her research matters, she says, because these findings are important in guiding policymakers to make appropriate decisions. Air pollution has always been a problem, especially in certain areas of South Africa. It affects the respiratory and cardiovascular systems of people who live in areas with high levels of air pollutants. Coupled with COVID-19, which also affects the respiratory system, this combination could place a great burden on already strained healthcare systems.
  
  Dr Olutola is part of a research group that is conducting epidemiology studies on the interaction effects of air pollution and climate change indicators on mortality and morbidity in South Africa. She is also involved with another research group that is working on the health effects of metals in women and in utero babies.
  
  From 2015 to 2017, the late Professor George Djolov of the Department of Geography, Geoinformatics and Meteorology in UP’s Faculty of Natural and Agricultural Sciences worked with Dr Olutola to use the Air Dispersion Potential (ADP) index for her PhD Studies. “Unfortunately, we could not continue because he passed away,” she says.
  
  Professor Djolov, who was born in Bulgaria, had an extraordinary academic career at various universities in southern Africa, among others. After his formal retirement, he joined UP as a meteorologist and Extraordinary Professor in 2007, and was highly active over the following decade. In his final three years, he managed the UP Laboratory for Atmospheric Studies.
  Dr Olutola says that Prof Halina Rollin of the School of Health Systems and Public Health inspired her research efforts. “She is never tired and is always full of ideas for research.” Dr Olutola has many academic role models, and particularly admires Prof Janine Wichmann’s work ethic. “Prof Wichmann is always there to support students, not necessarily only ‘her’ students. During my PhD studies, I could ask for her professional advice whenever I was stuck.”
  
  Dr Olutola’s dream is to be able to continue doing research, especially in the field of epidemiology. She encourages school learners and undergraduates interested in her field to continue to learn and to never give up.
  For recreation, she watches documentaries.
  

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