We rightly pay attention to CO₂ and methane, says Chang Foo, but more consideration is needed of the dangers of other toxic substances associated with poor air quality and numerous illnesses.
The release of greenhouse gases into the atmosphere has long been known to contribute to climate change, with carbon dioxide and methane being the subject of many global and national mitigation strategies that aim to break the vicious cycle of global warming. However, these gases are not the only emissions that should be a cause for concern.
A less discussed topic is the disastrous impact that noxious gases, airborne particulate matter and volatile organic compounds (VOCs) are having on human health. These toxic substances have been associated with a host of illnesses – including strokes, chronic respiratory diseases, lung cancers, and heart attacks. The World Health Organisation (WHO) has stated that poor air quality is linked to around seven million premature deaths per year, making it the single greatest environmental risk to human health [1]. Here I take take a look at the health problems caused by air pollution, the steps being taken to reduce its impact on the global population, and the monitoring solutions that are required to document the effects of these mitigation strategies.
Air quality
Air quality has been an issue since the dawn of the industrial revolution, with the potential sources of airborne pollution only becoming more numerous and wide-ranging as technology has advanced. The diversity and toxicity of the compounds emitted by everything from motor vehicles to power plants have led the WHO to establish global air quality guidelines for the worst offenders, including fine and coarse particulate matter, ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide.
Alarmingly, it estimates that 99% of the global population is actually breathing air that exceeds the recommended limits for at least some of these pollutants [2]. Cities in developing countries are often the hardest hit, due to the combination of minimal pollution regulation, concentrated emission sources and tightly packed buildings that prevent smog dispersion. This can be clearly seen in Delhi, India, which has some of the worst air quality in the entire world. Exposure to such high levels of pollution is estimated to be equivalent to smoking more than two packs of cigarettes a day and is leading to severe lung damage in roughly 40% of the city’s juvenile population [3].
Global awareness
Fortunately, global awareness of the dangers of poor air quality is steadily increasing, and the United Nations (UN) Environment Assembly has successfully adopted the ‘Preventing and reducing air pollution to improve air quality globally’ resolution, requiring the regular assessment of member state’s progress in implementing key actions designed to significantly improve air quality [4].
The UN General Assembly has also begun to take meaningful steps, with its member states signing onto resolutions that contain environmental protection and air quality subsections, such as ‘The future we want’ [5] and ‘Transforming our world: 2030 agenda for sustainable development’ [6]. These international pledges – coupled with initiatives to raise awareness such as ‘The international day of clean air for blue skies’ [7] – mark the UN’s commitment to substantially reducing the number of illnesses and deaths caused by polluted air, water and ground by 2030, giving particular attention to inner-city air quality and waste management.
Monitoring solutions
It is crucial to be able to accurately track changes in air quality to assess the impact of these mitigation strategies, and there are many state-of-the-art technologies that allow real-time monitoring of the most common and hazardous pollutants. Electrochemical analysers are perfectly suited to the measurement of noxious gases – such as nitrogen dioxide, carbon monoxide and ozone – and are sensitive enough to detect even minute concentrations of these harmful pollutants.
To determine the concentration of particulates in the air, optical counters are generally the go-to solution and function by measuring the amount of scattering caused by individual particles as they pass through a beam of light. Finally, photoionisation detectors are generally employed for VOC measurements, using an ultraviolet lamp to identify the unique ionisation fingerprints of the most common organic compounds.
Thermo Fisher Scientific offers a suite of innovative products to monitor various pollutants, such as the Thermo Scientific TVA2020 Toxic Vapor Analyser, which combines multiple measurement techniques to detect virtually all organic and inorganic compounds with a single portable unit. Such solutions can be employed across a wide range of applications, from traffic pollution measurements to fenceline emissions monitoring of natural gas processing plants.
The technologies discussed so far are perfectly suited to localised measurements and can accurately determine air pollution at ground level. To complement this, space-based observations of tropospheric pollutants – like those carried out by the Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite instrument [8] – can give an indication of air pollution levels on a national scale, as well as track harmful chemicals being transported across international borders by global weather patterns.
Going forwards
The transboundary nature of air pollution highlights the need for a collective global responsibility. It is imperative that both the UN and government institutions around the world continue to employ meaningful mitigative strategies in the quest for cleaner air. Rigorous monitoring programs must also be implemented to assess the efficacy of these measures, including dedicated air quality monitors that are capable of simultaneously detecting the concentration levels of noxious gases, VOCs and particulates. These localised measurements, coupled with space-based tropospheric observations, will generate the necessary data to establish whether the global community is doing enough to reduce toxic emissions, improve air quality and – most importantly – prevent millions of premature deaths per year.
Chang Foo is Strategic Marketing Manager at Thermo Fisher Scientific
References:
1 Seven million premature deaths annually linked to air pollution. World Health Organisation. https://www.who.int/news/ item/25-03-2014-7-millionpremature- deaths-annuallylinked- to-air-pollution. Accessed 18.01.23
2 Billions of people still breathe unhealthy air: new WHO data. World Health Organisation. https://www.who.int/news/item/04-04-2022-billions-ofpeople-still-breathe-unhealthyair-new-who-data. Accessed 18.01.23
3 Delhi's air pollution is triggering a health crisis. BBC News. https://www.bbc.co.uk/news/worldasia-india-41925067. Accessed 19.01.23
4 Actions on air quality report update. United Nations. https://www.unep.org/explore-topics/air/what-we-do/taking-stock-globalefforts/actions-air-quality-reportupdate. Accessed 18.01.23
5 The future we want – outcome document. United Nations. https://sustainabledevelop ment.un.org/futurewewant.html. Accessed 18.01.23
6 Transforming our world: the 2030 agenda for sustainable development. United Nations. https://sdgs.un.org/2030agenda. Accessed 18.01.23
7 International day of clean air for blue skies. United Nations. https://www.un.org/en/observances/clean-air-day. Accessed 18.01.23
8 TEMPO: A New Era of Air Quality Monitoring from Space. United States Environmental Protection Agency. https://www.epa.gov/sciencematters/temponew- era-air-quality-monitoringspace. Accessed 19.01.23
