The dangers of aircraft emissions exposure during pregnancy
Ruth Stephen and Sarah Stephen
A recently published study drew an association between exposure of women (during pregnancy) to ultrafine particle (UFP) emissions from aircrafts and an increased risk of preterm babies. It is the first study to show such an alarming link between premature birth in women living in the incoming flight path and downwind of a major airport (in this case, Los Angeles International Airport). Given the seriousness of the study’s findings, we highlight key takeaway messages from the study and deliver implications for governmental policy and stakeholder action.
Preterm births
A preterm birth is one that happens before 37 completed weeks of pregnancy. Approximately 7% of births in the UK are preterm, accounting to around 60,000 babies born prematurely every year. Preterm birth is associated with risk in babies for developing complications, including respiratory problems, vision or hearing deficiencies, infections, developmental delays, and is the leading cause of death in newborns.
The study in detail
Scientists at the University of California, Los Angeles, published their findings in the scientific journal Environmental Health Perspectives. They had examined the birth records of 174,186 mothers living within 15 kilometres of the airport and who gave birth during 2008–2016, along with calculating the amount of exposure to UFPs emitted by airplanes during their pregnancy. During this period, there were 15,134 premature births. The researchers found that risk is highest with exposure to aircraft UFPs compared to that with traffic-related air pollution and aircraft noise.
The unaddressed menace of UFP exposures from aircraft
Airplanes produce pollutant trails during take-off, landing, and taxiing in the runway. Particulate matter, especially UFPs, which are less than 0.1μm in diameter, are major pollutants from jet engines, in addition to volatile organic compounds and oxides of sulphur and nitrogen. Unlike particulate matter of sizes less than 2.5μm (PM2.5) and those less than 10μm in diameter (PM10), UFPs are not routinely monitored or regulated. This gap is highlighted by Dr. Stefan Reis of the UK Centre for Ecology and Hydrology, Edinburgh: “With regard to UFP, there are currently no public health effects standards or limit values established for UFP, and there are no routine observations undertaken as part of the official national monitoring networks.” In fact, in their recent report to Department for Environment, Food, and Rural Affairs (Defra) the UK Air Quality Expert Group had recommended “… given the predicted growth in emissions from aviation, it would be prudent to establish a permanent site, monitoring particle number concentration and size distribution in the vicinity of a major airport.”
Health implications of UFP exposures
Although UFPs account little in terms of particle mass, these constitute the majority of particles and surface area. In fact, UFPs on an equal mass basis may have higher detrimental impact on health than PM2.5 and PM10. This is because the small size facilitates easy entry of the UFPs into the thin membranes of the lung during inhalation and could be carried by the blood to distant parts of the body, including the placenta. UFPs also have the ability to escape the body’s usual surveillance and clearance mechanisms that remove larger particles like PM10 and PM2.5. Another unique trait of the UFPs is the ability to trap and transport other harmful chemicals in the atmosphere, such as polyaromatic hydrocarbons that are byproducts of automobile emissions, which could then lead to inflammation and associated detrimental health effects.
Commenting on the study, Professor Paul Monks, who chaired the Air Quality Expert Group says, “Ultrafine particles are some of the smallest and most dynamic particles in the atmosphere. This contributes to the growing evidence body of adverse health effects for UFP exposure and highlights the negative impact of air traffic UFP sources on preterm birth. Given the lack of regulation or standards for particle number, UFP emissions have not been well characterized and this study points to an urgent need to assess these particularly around airports.”
When we place these arguments in light of the findings from the study, there emerges an enormous public health concern and serious implications for expectant mothers who reside in areas with elevated UFP exposures, i.e. in the densely populated residential areas that fall in the downwind of airports in many parts of the world.
Towards greener skies and healthier lives
The aviation sector is currently emerging from a standstill following the COVID-19 pandemic. The near-suspension of operations and the associated financial losses have led to numerous airline companies approaching national governments for bailouts and subsidies. The question is whether governments should provide bailouts unconditionally, with the result that airline companies return to a pre-pandemic status quo with little accountability for the health impacts of their operations.
When asked whether the airline industry should change in the way it works after the lockdown is lifted, Professor Cameron Hepburn, Director, Smith School of Enterprise at the University of Oxford, has strong words: “The aviation industry has had to come cap in hand to government. Any government bailout for aviation should be conditional on a clear plan and pathway to a net zero emissions future. Financial consequences should follow if bailed out airlines fail to make good on these plans. It is not enough to merely offset the growth in emissions when emissions need to decline to zero. Aviation needs to shift gear on technology and start seriously innovating if it is to part of a net zero emissions future.”
The study on UFP emissions from a major airport has highlighted the urgent need for controlling emissions that are harmful for expectant mothers and unborn babies. Simultaneously, there are also calls for airline companies reducing their carbon footprint.
This period of near-standstill is best for designing and implementing controls not only on the reduction of the aviation sector’s carbon footprint, but also on toxic emissions, such as UFP. In fact, governmental authorities and regulators are now provided with an excellent opportunity for taking an upper hand in steering this sector into responsible behaviour by making such controls part of any bailouts extended. From the companies’ point of view, this is also efficient as this can be incorporated when revising their operational strategies for ensuring that they are not consigned to extinction.
A greener and healthier future for all of earth’s inhabitants is within reach, but powerful stakeholders have the responsibility of ensuring that this opportunity is not squandered.
