Background
Summary of Council decision:
Five issues were investigated, of which two were Upheld and three were Not upheld.
Ad description
A TV ad, four radio ads and a press ad for Transport for London’s Ultra Low Emission Zone (ULEZ) expansion, seen and heard between January and June 2023:
a. The TV ad showed a car driving and emitting exhaust smoke. A pedestrian was shown coughing. The voiceover said, “London has an urgent air quality problem and it is impacting the health of Londoners. So to help clear the city’s air the Ultra Low Emission Zone is expanding across all London boroughs from the 29th August this year … Because every journey matters.” A bird was shown flying and people were running and participating in other activities in the city.
b. The first radio ad said, “Drivers we need you to check your vehicles because the Ultra Low Emission Zone is expanding across all London boroughs from the 29th August this year, to help clear London’s air and improve health for you, your family and every Londoner … To the Mayor of London and TfL every journey matters.”
c. The second radio ad said, “Poor air quality is affecting the health of Londoners. I’m Sarah Woolnough, I am the chief executive of Asthma and Lung UK. Road traffic is a major source of air pollution in London. We are passionate about improving the air we breathe. To improve London’s air we are really supportive of the expanded ULEZ. The Central London ULEZ has shown you can reduce air pollution, we have seen almost a halving of levels of nitrogen dioxide. To help clear London’s air and improve health the Ultra Low Emission Zone is expanding across all London boroughs from 29th August this year …”
d. The third radio ad stated, “Did you know that most air pollution related deaths actually occur in Outer London areas?”, “Oh wow, no, I didn't know that. It's higher than in Central London?”, “It’s obviously a concern, considering our parents are more vulnerable”, “That's why the Ultra Low Emission Zone is expanding across all London boroughs from the 29th of August this year to help make the air clearer.”
e. The fourth radio ad stated, “Poor air quality is affecting the health of Londoners.” “Recent reports have shown a link between air pollution and an increased risk of developing dementia. We believe risk factors, such as air pollution, account for 40 per cent of dementia cases, many of which could be avoided. With almost one million people living with dementia in the UK – reducing our risk is extremely important. It’s really encouraging to see the ambition at a local level to reduce air pollution and help reduce the risk of developing dementia.” “To help clear London’s air and improve health the Ultra Low Emission Zone is expanding across all London boroughs from 29th August this year.”
f. The press ad seen in the Metro stated, “London has an urgent air quality problem. That is why the ULEZ is expanding across all London boroughs from 29 August 2023 … The ULEZ has already made a significant difference by helping to reduce harmful nitrogen dioxide pollution by nearly half in Central London.”
Issue
The ASA received 503 complaints. The complainants challenged whether the following claims were misleading and could be substantiated:
1. in ad (a) “London has an urgent air quality problem”;
2. in ads (a) and (b) respectively, for the ULEZ expansion to “help clear the city’s air” and “help clear London’s air”;
3. in ads (c) and (f) respectively, in relation to the ULEZ in Central London,“we have seen almost a halving of levels of nitrogen dioxide” and “helping to reduce harmful nitrogen dioxide pollution by nearly half”;
4. in ad (d) “Did you know that most air pollution related deaths actually occur in Outer London areas?”; and
5. in ad (e) “Recent reports have shown a link between air pollution and an increased risk of developing dementia”.
Response
1. Transport for London (TfL) said the Mayor of London, the UK Government, the World Health Organisation (WHO) and health experts worldwide recognised the impact on health that air pollution had.
They explained that in 2019 in Greater London, between 3,600 and 4,100 deaths were estimated to be attributed to air pollution and if no further action was taken to reduce it around 550,000 Londoners would develop diseases related to poor air quality over the next 30 years. The cost to the NHS and the social care system in London for that was estimated to be £10.4 billion by 2050.
They said that the Regional Director for London in the Office for Health Improvement and Disparities (OHID) had described air pollution as the biggest environmental health risk currently being faced. The OHID had said London had the highest percentage of deaths attributed to air pollution, of all English regions, with an estimated 4,000 deaths per year and while air pollution affected all those in London, the poorest and most vulnerable were most impacted. The OHID further said that action on air pollution could not wait and needed to be tackled with the urgency and ambition it demanded, to safeguard younger people and future generations.
TfL stated that the UK Chief Medical Officer’s Annual Report, published in December 2022, included information on deaths from air pollution. The report mentioned that for the first time a death had specifically been linked to air pollution - a child from South London, who the coroner stated had died of asthma, contributed to by exposure to excessive pollution.
TfL said the WHO and the European Union (EU) had recognised that stricter air quality targets were needed to protect people’s health and the UK government had set a new limit for particulate matter with a diameter of 2.5 micrometres or less (PM2.5) to be in force by 2040. TfL stated that nowhere in London currently met the WHO 2021 Air Quality Guideline for nitrogen dioxide (NO2) or PM2.5, and improving air pollution and moving towards those guidelines should be done as soon as possible. It was therefore an urgent problem that required immediate action.
Clearcast said, in relation to ad (a), they were provided with evidence, including published research and a paper from Imperial College London and a number of reports and statements from the Committee on the Medical Effects of Air Pollutants (COMEAP), including a review of air pollution research on dementia and cognitive decline, effects on mortality by NO2, the effects of air pollution on cardiovascular disease and the effect on mortality for long-term exposure to air pollution.
They stated that the latest Department for Environment Food and Rural Affairs (DEFRA) report stated that London did not meet the legal limits for NO2. Separately London did not meet the WHO guidelines and targets published in September 2021.
They said based on that information, and especially because London did not meet the legal limits for air quality, they believed London had an urgent air quality problem and the ad itself included verification signposting the viewer to where to find more information about how London was impacted by air quality.
2. TfL said for the 2023 ULEZ expansion, air quality modelling was undertaken by Imperial College London working with TfL. The modelling looked at NO2, particulate matter with a diameter of 10 micrometres or less (PM10) and PM2.5 which were generally accepted indicators of air quality.
Modelled air pollutant concentrations were based on those listed in the London Atmospheric Emissions Inventory (LAEI). The LAEI was a comprehensive inventory of all emissions across London, up to and including the M25, including transport, industrial and commercial, domestic and other miscellaneous sources such as agriculture or accidental fire.
TfL also estimated changes to road traffic (such as people moving from cars to more sustainable modes of transport like cycling, public transport or walking) and vehicle changes from drivers who switched to ULEZ compliant vehicles. Those estimates were then fed into the LAEI.
They said that results, which were published in their consultation document, ‘Our proposals to help improve air quality, tackle the climate emergency and reduce congestion by expanding the ULEZ London-wide and other measures report’, showed NOx (the collective term for nitrous oxide and nitrogen dioxide) emission reductions in Central, Inner and Outer London. The area with the biggest changes, and so the largest improvement in air quality, was Outer London. For PM2.5, while the modelling showed a reduction across all of London for cars and vans, overall concentrations were expected to remain largely the same. In more local areas there would be small improvements but equally in other local areas there would be a small increase (due to changes in traffic flow). The modelling further highlighted that an additional 44,200 people in Inner and Outer London would live in areas where PM2.5 concentrations were below the WHO interim target of 10 µg/m3 for the first time. They said for PM10 emissions, the results showed that there would be a reduction for all vehicles and across the whole of London from the expansion.
They said that information was used in the “Integrated Impact Assessment” study produced by Jacobs (the Jacobs Report), a business consultancy firm. They said the Jacobs Report was published in May 2022 and looked at the potential positive and negative environmental, economic, health and equalities impacts of the ULEZ proposal. It also identified measures to enhance or mitigate impacts.
The Jacobs Report noted impacts varied due to location. It explained that the London wide ULEZ expansion was expected to result in a moderate reduction in NOx in Outer London and across Greater London, minor reductions in PM2.5 and PM10 in Outer London and across Greater London, minor to negligible changes in NOx in Central and Inner London where the existing ULEZ operated and negligible changes in PM2.5 and PM10 in Central and Inner London where the existing ULEZ operated.
The report stated that the ULEZ expansion would benefit five million Londoners who live in Outer London, as well as those visiting and working in the city. Also it was forecast to reduce NOx emissions in Outer London from cars and vans by 10 and 7% respectively in 2023.
They said the forecasted reductions in NO2 concentrations in the report would mean tens of thousands of Londoners would benefit from cleaner air and nearly 340,000 would live in areas meeting the WHO interim target. London’s most deprived communities would experience an improvement in air quality, with 99.9% living in areas with improved NO2 concentrations and 97% would live in areas with improved PM2.5 concentrations.
The Jacobs Report concluded that all benefits across Greater London were either moderate or minor. In those circumstances it was accurate and appropriate to state that the expanded ULEZ was expected to “help clear the city’s air”.Clearcast said, in relation to ad (a), they had seen details of the LAEI 2019 report which provided a breakdown of pollutant emissions by source. They had also been supplied with a November 2021 study written by Imperial College London, “Has the ultra low emission zone in London improved air quality?" It concluded that the ULEZ was one element of a multi-faceted set of policies which would lead to improved air quality.
They said that from the evidence provided it was clear that preventing older and more polluting vehicles being on the road would help clear London’s air. They noted that the ad only said ‘to help clear the city’s air’ and had not stated that the ULEZ alone would clear London’s air, just that it helped to do so.
3. TfL said the level of NO2 had almost halved due to the existing Central London ULEZ. They had published several reports on the impact of the ULEZ scheme which all had been peer reviewed by the environment Research Group at Imperial College. They explained that in Central London, NO2 concentrations had been estimated to be 44% lower after six months than they would have been without the ULEZ, and 46% lower after one year.
They explained that their figures were based on an impact assessment and used estimates based on the difference between a non-ULEZ and a ULEZ scenario. While they had known NO2 data from air-quality monitoring they said that did not provide a suitably robust assessment of the impact of ULEZ in the way an impact assessment did.
They stated that to successfully measure the impact of a policy intervention like the Central ULEZ it was necessary to measure pre-compliance and not just consider results from when the policy began or shortly after. Pre-compliance for the Central ULEZ was stimulated by a number of events. That included the initial announcement in 2017 of the proposed implementation of the scheme. There were also early marketing campaigns for drivers and engagement with businesses operating in the relevant areas and the launch of the scrappage scheme to assist pre-compliance and help non-compliant vehicle owners. Finally, there were long-term changes to TfL fleets such as buses, taxis and private hire vehicles which began with the initial consultation and went beyond the implementation of the scheme.
They said for those reasons it was not appropriate to consider the impact of the scheme from the day it began and assume the affected population changed their behaviour on that day. That was especially the case for individuals who used the scrappage scheme or purchased new vehicles in response to the scheme, which would have taken time and planning. They were examples of the overall intent of the scheme, which was to incentivise people to not pay the charge by acting in advance.
They added that if the policy was considered only from the first few months of its introduction, this would not allow a sufficiently long enough time period to measure the emissions reduction, account for any weather or seasonality changes or consider fleet changes. It also missed out the NO2 concentrations TfL were monitoring prior to the launch.
Radiocentre said they had accepted detailed evidence from TfL. The ULEZ six-month and twelve-month reports supported the claim.
4. TfL provided a 2021 report they had commissioned from the Environmental Research Group (ERG) at Imperial College London, who, they explained, were recognised as a world-leading authority on air pollution. TfL said the report titled “London Health Burden of Current Air Pollution and Future Health Benefits of Mayoral Air Quality Policies”, was the latest report on the health burden of long-term exposure to pollution in London. The report detailed the impact air pollution, specifically PM2.5 and NO2, was having on mortality across London and the level of influence future Mayoral policies could have on it.
TfL said no single official definition of “Inner London” and “Outer London” areas existed. Ad (d)’s reference to the expansion of the ULEZ across all London boroughs was intended to reflect how the ULEZ would cover all London boroughs after its expansion. They provided a table that outlined three different permutations of Inner and Outer London and said that under each framing the claim “most air pollution related deaths actually occur in Outer London areas” had been substantiated.
TfL said a range of factors influenced the impact of air pollution on mortality. One factor was age, and they highlighted that there was a higher number of older people in Outer London than in Inner London. They said that explained why Outer London boroughs had higher numbers of air pollution-related deaths, despite having lower overall levels of pollution. They said 14% of the population of Outer London, approximately 680,000 people, was aged 65 and over, whereas 10% of Inner London residents, approximately 380,000 people, were aged 65 and over. Those statistics were taken from the Office of National Statistics’ (ONS) Census Output Area Population estimates from mid-2019.
TfL said it was well established that air pollution had negative effects on health throughout life, from pre-birth to old age. They highlighted how The Chief Medical Officer’s Annual Report in 2022 had stated that the deaths attributable to air pollution in England were estimated to be between 26,000 and 38,000 a year. They said air pollution also increased the risk of developing heart disease, strokes, lung disease, and lung cancer and it reduced life expectancy.
Radiocentre said they had cleared ad (d) for broadcast on the basis of the report prepared by the ERG.
5. TfL said ad (e) had not claimed a direct link between air pollution and developing dementia, nor that air pollution was the only contributing factor in its development. Their intention had been to highlight the recent reports that had explored a link between the two. They said the claims in the ad were based on the UK Health Security Agency’s Committee on the Medical Effects of Air Pollutants’ (COMEAP) 2022 report “Air Pollution: cognitive decline and dementia”. That report had concluded it was likely that air pollution did contribute to an increased risk of mental decline and the development of dementia in older people.
TfL also provided a 2020 report from The Lancet Commission on dementia prevention, intervention and care, published in The Lancet journal. The report had concluded that 40% of dementia cases could have been prevented or delayed by targeting 12 modifiable risk factors, one of which was air pollution. They also provided a 2016 Royal College of Physicians report titled “Every Breath We Take: the lifelong impact of air pollution” which concluded air pollution has been linked to cancer, asthma, stroke and heart disease, diabetes, obesity, and changes linked to dementia. They said there was an increasing body of evidence that showed the link between breathing polluted air and a wide range of health effects including dementia, Type 2 diabetes, and adverse effects on foetal growth and birth.
Radiocentre said they had cleared ad (e) for broadcast on the basis of the 2020 Lancet Commission report.
Assessment
1.Not Upheld
Ad (a) stated, “London has an urgent air quality problem and it is impacting the health of Londoners”.
The WHO had stated that air pollution was, “one of the greatest environmental risks to health” and attributed it to 6.7 million premature deaths annually worldwide. Defra acknowledged that air pollution could cause both short- and long-term effects on health, including increasing the symptoms and inflammation of those suffering from heart and lung diseases. Further to that the Chief Medical Officer’s 2022 Annual Report stated that the, “mortality burden of air pollution in England is estimated to be between 26,000 and 38,000 a year, but in addition many people suffer avoidable chronic ill health as a result of it. Improvements in air quality have been associated with improved health outcomes – for example, reductions in air pollution in London have led to reduced childhood asthma hospital admissions. Further reductions in air pollution will lead to significant reductions in coronary heart disease, stroke and lung cancer, among others”. We therefore understood that the link between air pollution and ill-health was indisputable among those bodies.
Regarding air quality there were different standards of maximum limits of problematic particulates. There were the legal limits set by government and there were non-statutory recommendations made by organisations such as the WHO.
We understood that a Defra report, published in September 2022, and entitled, “Air Pollution in the UK 2021”, stated that in 2021, the latest year they had figures for, the Greater London Urban Area did not meet the legal annual mean limit for NO2, one of the primary problematic particulates for air pollution.
Based on the legal non-compliance with the NO2 annual mean limit value, which we understood had been in exceedance since 2010, it was reasonable for TfL to state that London did have an air quality problem. In addition, because of the widespread evidence and consensus that air pollution did have significant detrimental effects on people’s health, including 6.7 million premature deaths the WHO attributed pollution to, it was an urgent problem and we concluded that the claim was unlikely to mislead.
On that point, we investigated the ad under BCAP Code rules 3.1 (Misleading advertising), 3.9 (Substantiation), but did not find it in breach.
2. Not upheld
Ad (a) stated “to help clear the city’s air the Ultra Low Emission Zone is expanding across all London boroughs” and ad (b) stated “the Ultra Low Emission Zone is expanding across all London boroughs … to help clear London’s air”.
The TfL consultation document outlined the forecasted changes to road traffic TfL expected in response to the expanded ULEZ and the impact that would have on emissions. They had used a number of datasets to estimate the number of vehicles that would be affected by the ULEZ expansion and of those vehicles the proportion that were compliant with the future ULEZ standards.
TfL had then taken those figures to estimate how the remaining proportion of owners of the estimated non-compliant vehicles might change their travel behaviour in response to the ULEZ charge. They predicted the number of non-compliant car owners who would either switch to a compliant vehicle, not drive at all, find an alternative method of transport or reroute their car to avoid the charging area.
TfL next used the figures generated from the estimated change in traffic volume and vehicle fleet, and applied them to the LAEI. The LAEI was an inventory of all emissions across London from a comprehensive range of sources, including road transport. The LAEI then modelled air pollutant concentrations, including NO2, PM2.5 and PM10 which were the particulates of the greatest concern. Using the estimated figures from TfL about road traffic changes, the LAEI model was then able to predict the effect on NO2, PM2.5 and PM10 caused by road traffic. The resulting figures showed a reduction of NOx in Greater London by 5.4% and a 5.5% reduction outside of Greater London (but within the region of the air quality study). For PM2.5 the results showed a 1.5% reduction in Greater London and a 1.4% reduction outside of Greater London (but within the region of the air quality study). For PM10 the results showed a 1% reduction in Greater London and a 1.5% reduction outside of Greater London (but within the region of the air quality study). In addition the average exposure of the population of Greater London to NO2 would experience a 1.3% reduction and those outside of Greater London a 1.1% reduction. For PM2.5, the reduction in Greater London and outside of Greater London were both negligible.
The Jacobs Report was produced by a business consultancy firm on behalf of TfL. It used the modelled traffic figures and resulting air pollution statistics generated in TfL’s consultation document to identify key impacts of the proposed ULEZ, including changes in emissions of air pollutants. The impacts were expressed on a scale of minus three to plus three, with one being minor, two moderate and three major.
The Jacobs report stated that regarding the impact of the predicted reductions in NOx emissions in 2023 after the ULEZ extension, for Greater London and outside of Greater London, they would both be “moderate”. Concerning PM2.5 and PM10 emissions the predicted reductions in Greater London and outside of Greater London would all have had a “minor” impact. Further to that, for NO2 the report showed the predicted reduction of average exposure of the population of Greater London and outside of Greater London respectively, would both have a “minor” impact. For PM2.5 the reduction in Greater London and outside of Greater London were both a “negligible” impact.
Therefore, the results from the Jacobs Report showed that the implementation of the expanded ULEZ would reduce air pollution emissions and concentrations in Greater London and beyond to varying degrees; from negligible to moderate, according to the scale applied.
The ads claimed that the ULEZ expansion was being implemented to help clear London’s/the city’s air and whilst the data indicated some improvement in relation to all air quality factors, the advert did not claim the ULEZ would be the single factor to improve air quality overall. We concluded that claims for the extension to help improve air quality were unlikely to mislead.
On that point, we investigated ads (a) and (b) under BCAP Code rules 3.1 (Misleading advertising), 3.9 (Substantiation) and 9.8 (Environmental Claims), but did not find them in breach.
3. Upheld
Ad (c) stated that it had been seen that NO2 had reduced by almost a half since the implementation of the ULEZ in Central London. Ad (f) said that the ULEZ was expanding across all London boroughs, but it had already made a significant difference by helping to reduce NO2 by nearly half in Central London.
The TfL document “ULEZ one year report” stated that in October 2022 there had been an estimated 46% reduction in Central London roadside NO2 concentrations compared to a “no ULEZ” scenario.To calculate the reduction, TfL had used data from roadside monitoring sites for the period January 2017 until October 2022 for Central, Inner and Outer London. They had calculated the proportion of NO2 concentrations attributed to traffic alone. Then they had considered how NO2 concentrations had been impacted from sources outside the ULEZ, for instance, the nationwide shift of vehicles to newer, less polluting cars that was happening regardless of the ULEZ. Using that approach they had then calculated the difference between a non-ULEZ and a ULEZ scenario in October 2022.
While we acknowledged TfL’s explanation of the basis of the percentage calculation, the claims “The Central London ULEZ has shown you can reduce air pollution, we have seen almost a halving of levels of nitrogen dioxide” and “The ULEZ has already made a significant difference by helping to reduce harmful nitrogen dioxide pollution by nearly half …” were likely to be understood as representative of the reduction in NO2 as recorded by, for example, air quality sampling before the introduction of the charges and since the implementation of the Central London ULEZ, rather than being based on the calculated difference between a non-ULEZ and a ULEZ scenario. Clear qualification was, therefore, required in order to ensure that the claims would be fully understood.
Because the basis of the claims was not given, we concluded that the ads were likely to mislead.
Ad (c) breached BCAP Code rules 3.1 and 3.2 (Misleading Advertising), 3.10 (Qualification) and 9.2 (Environmental Claims) and ad (f) breached CAP Code rules 3.1 and 3.3 (Misleading Advertising) and 3.9 (Qualification).
4. Upheld
The ASA understood no official definition of Outer London existed. We also understood the ULEZ had been introduced to Central London in 2019, and expanded to the Inner London area, inside the North and South Circular roads, in 2021. We considered, in the context of ad (d), which was about the ULEZ expansion, listeners would likely understand the term “Outer London” as referring to areas that had not already been covered by the ULEZ. We therefore considered listeners would understand the claim “most air pollution related deaths actually occur in Outer London areas” in ad (d) to refer to the proportion of air pollution-related deaths in the areas that had previously not been covered by the ULEZ.
The 2021 ERG report had been commissioned to assess air pollution levels in London, their impact, and what effects air quality policies could have. The report used mortality figures in London gathered by the ONS and air pollution levels from 2019, which were the most recent figures available, to calculate the “mortality burden” of air pollution – the fraction of deaths that could be attributed to air pollution – in London at that time.
We understood the figures relating to air pollution concentration in 2019 used in the mortality burden calculations had arisen from the London Air Quality Toolkit, a model provided with data from the London Atmospheric Emissions Inventory. Additionally, we understood that the number of deaths used within the mortality burden calculations had originated from ONS reporting that averaged data from 2016, 2017, and 2018 to estimate the number of deaths in 2019.
The report outlined the number of estimated attributable deaths in 2019 in each London borough from anthropogenic pollutants, specifically from PM2.5 and NO2. We understood, according to the framing of Outer London as based around boroughs that were either partially or not at all covered by the 2021 ULEZ, the estimated number of deaths attributable to air pollution in 2019 – the mortality burden – was 2,896 at the lowest estimate, and 3,321 at the highest. In Inner London, the estimated number of deaths attributable to air pollution in 2019 was 701 at the lowest estimate, and 777 at the highest estimate.
While the evidence indicated that the mortality burden in Outer London was greater than that of Inner London, the ad did not clarify that the claim “most air pollution related deaths actually occur in Outer London areas” was based on modelled estimates, using the latest available data. We acknowledged that scientific research into air pollution and health often involved the use of models and estimates, and that the approach of the ERG’s report was consistent with the Committee on the Medical Effects of Air Pollutants’, an independent Governmental advisory panel on the health effects of air pollution. However, we considered that listeners were likely to understand from the claim, which referred to ‘actual’ deaths, that the evidence supporting the claim was not estimated or modelled in anyway. Clear qualifying information to explain the basis of the claim was therefore required.
Because the basis of the claim was not explained and evidence to support the claim as it was likely to be interpreted was not supplied, we concluded that the ad was likely to mislead.
On that point, ad (d) breached BCAP Code rules 3.1 and 3.2 (Misleading advertising), 3.9 (Substantiation), 3.10 (Qualification) and 9.2 (Environmental claims).
5. Not upheld
Ad (e) stated “Recent reports have shown a link between air pollution and an increased risk of developing dementia”. We considered listeners would understand that, in the context of the ad which also stated “We believe risk factors, such as air pollution, account for 40 per cent of dementia cases, many of which could be avoided" to mean air pollution was a risk factor in developing dementia, and that those risk factors accounted for 40 per cent of dementia cases.
We reviewed the 2016 Royal College of Physicians report, which focused on a range of health conditions that could be linked to air pollution. However, the report did not directly focus on the relationship between air pollution and the development of dementia, it stated only that air pollution had been connected to changes linked to dementia. While indicative of a relationship between air-pollution and health, it did not go far enough to support the ad’s specific claim.
We reviewed the 2022 COMEAP report, prepared by the Committee on the Medical Effects of Air Pollutants, who advised the government on the health effects of air pollutants. The report was a literature review of 69 previously published papers that explored the link between air pollution and cognitive performance and decline. Of those 69 papers, 16 focused on the link between air pollution and dementia, and the report found that exposure to air pollution had been significantly associated with dementia in several studies. The report concluded that the epidemiological evidence suggested an association between exposure to ambient air pollutants and both the risk of developing dementia and acceleration of cognitive decline.
In 2017 the Lancet Commission on dementia prevention, intervention, and care (The Lancet Commission) identified nine potentially modifiable risk factors for dementia – obesity, depression, physical inactivity, low social contact, hypertension, diabetes, smoking, hearing loss, and lower education. The Lancet Commission’s 2020 report (the 2020 report), a systematic literature review, added three factors to that list – air pollution, traumatic brain injury, and drinking more than 21 units of alcohol a week. The 2020 report completed new reviews and meta-analyses and found that those 12 modifiable risk factors accounted for approximately 40% of worldwide dementias, which could theoretically have been prevented or delayed. The 2020 report concluded that of the 40% of dementia cases that could be attributed to modifiable risk factors, 2.3% of that 40% were linked to air pollution. It also concluded there was sufficient evidence to include air pollution as a risk factor in developing dementia, and recommended national and international policies to reduce population exposure to air pollution as a dementia risk reduction strategy.
The COMEAP report and the Lancet Commission’s 2020 report both concluded there was a link between air pollution and an increased risk of developing dementia. The 2020 report also concluded that 40% of dementia cases were due to risk factors, and that air pollution was one of them. We therefore considered it reasonable for TfL to make the claim in ad (e) and that it was unlikely to mislead.
On that point, we investigated ad (e) under BCAP Code rules 3.1 (Misleading advertising) and 3.9 (Substantiation), but did not find it in breach.
Action
We told Transport for London to ensure that the basis of all environmental claims was made clear in future ads.
BCAP Code
3.1 3.2 3.9 3.10 9.2 9.8 3.1 3.9
