Ad description

A national press ad for Puressentiel, seen on 15 February 2020, featured the headline "COULD THE AIR INSIDE YOUR HOME BE MORE POLLUTED THAN OUTDOORS? … Scientific research suggests that it could be". Text further down the ad stated "PURESSENTIEL PURIFYING AIR SPRAY … 100% PLANT-BASED FORMULA PROVEN TO REDUCE HOUSEHOLD BACTERIA". A footnote connected to that claim stated "Reduces bacteria on surfaces. Microbiological Environmental study, randomized, blind, controlled. May 18".


Two complainants, who understood the product could only reduce the level of bacteria on surfaces and not from the air, challenged whether the claim "PURESSENTIEL PURIFYING AIR SPRAY … PROVEN TO REDUCE HOUSEHOLD BACTERIA" was misleading.


Puressentiel UK Ltd provided an unpublished study and an EN Standard test report declaration in substantiation for the claim “PROVEN TO REDUCE HOUSEHOLD BACTERIA”. They also provided an expert letter, a journal article, and an unpublished study by way of substantiation for the statement “COULD THE AIR INSIDE YOUR HOME BE MORE POLLUTED THAN OUTDOORS? … Scientific research suggests that it could be".


Upheld The ASA noted that the headline of the ad was “COULD THE AIR INSIDE YOUR HOME BE MORE POLLUTED THAN OUTDOORS?” We considered that consumers would understand pollutants to consist of harmful rather than harmless bacteria. In that context, we considered consumers would understand the claim “PURESSENTIEL PURIFYING AIR SPRAY … 100% PLANT-BASED FORMULA PROVEN TO REDUCE HOUSEHOLD BACTERIA”, to mean that using Puressentiel’s air spray would reduce harmful indoor airborne household bacteria. We noted the document that showed the spray’s bactericidal efficacy to EN Standards 13697 and 13727. We also noted the former Standard measured a biocide’s effectiveness as a surface disinfectant, and the latter a biocide’s effectiveness as a disinfectant and antiseptic when suspended in water. While we understood the document showed that the product was in compliance with the specifications for those Standards, neither of the Standards made reference to a biocide’s efficacy specifically in reducing airborne bacteria. Moreover, Standard 13697 referred specifically to surface disinfectants, which we considered were not the subject of the claim made in the ad. The unpublished study provided by Puressentiel was a randomised, controlled, blinded study that used passive sampling methods of the air. The study concluded that Puressentiel’s spray could reduce airborne bacteria by 69%. We noted the study did not specify whether that 69% reduction referred exclusively to harmful bacteria, or whether it included harmless bacteria. We also noted the study had been carried out in an office environment in central London, which we considered was not similar to the domestic environment in which the product was intended to be used. Furthermore, the paper stated that the weather at the time of the study was “unseasonably warm”, which we considered would have had an impact on the level of pollutants in the space where the study was carried out. We noted the expert opinion on the assertion that indoor air could be more polluted than air outdoor. We considered that although there appeared to be a growing body of evidence in that area, the letter referred to airborne pollutants such as carbon dioxide and carbon monoxide. While there appeared to be some evidence that indoor sources, such as emissions from cooking, were a contributing factor, the letter did not make reference to airborne bacteria, which we understood was the form of indoor pollutant that was the subject of the ad. We therefore considered the letter was not adequate substantiation for the claim that indoor air was more than or as polluted as outdoor air. We noted the published and unpublished studies provided by Puressentiel. Both studies concerned the potential use of purifying sprays and essential oils in relation to their effect on medical conditions and so we considered they were not relevant to the claim about indoor air pollution. Because we had not seen adequate evidence that Puressentiel’s air spray was capable of reducing harmful airborne bacteria in domestic environments, we concluded that the claim “PROVEN TO REDUCE HOUSEHOLD BACTERIA” misleadingly exaggerated the capabilities of the product and had not been substantiated. The ad breached CAP Code (Edition 12) rules  3.1 3.1 Advertisements must not materially mislead or be likely to do so.  (Misleading advertising),  3.7 3.7 Advertisements must not falsely imply that the advertiser is acting as a consumer or for purposes outside its trade, business, craft or profession. Advertisements must make clear their commercial intent, if that is not obvious from the context.  (Substantiation), and  3.11 3.11 Qualifications must be presented clearly.
BCAP has published guidance on superimposed text to help television broadcasters ensure compliance with rule  3.1 3.1 Advertisements must not materially mislead or be likely to do so.  . The guidance is available at:
Use of superimposed text in television advertising


The ad must not appear again in the form complained about. We told Puressentiel UK Ltd to ensure they did not claim their air spray was proven to reduce airborne household bacteria unless they held evidence to demonstrate that was the case.


3.1     3.7     3.11    

CAP Code (Edition 12)

3.1     3.7     3.11    

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