21-05-2025
Why perfume could be bad for you
Wearing perfume or using a fragranced body lotion could be bad for health, a study suggests.
Ingredients in perfume have been shown for the first time to interfere with a protective invisible cloud around human skin that is thought to clean and filter the air we breathe.
The scents are themselves harmless to human health but by interfering with the protective cloud that clings to our skin they could be diminishing the benefits it provides, scientists believe.
Researchers at the University of California Irvine and Max Planck Institute discovered the skin cloud in 2022, which is technically known as an 'oxidation field'.
They found that ozone in the air reacts with natural oils on the surface of our skin, such as squalene, a chemical which keeps skin supple, and creates short-lived particles called OH radicals through a process called ozonolysis, which form a protective bubble around the body.
OH radicals are highly reactive and neutralise toxic molecules which has earned them the nickname 'detergents of the atmosphere' for their cleaning properties. They target pollutants in the air but also help clean surfaces.
A study of four volunteers, published in the journal Science Advances, investigated what happens to the chemical cloud when people have no products on their skin, after they apply perfume, when wearing lotion and after dabbing scented essential oils on their skin.
Data show that the perfume used in the study, the unisex CK One, diminished the cloud by 86 per cent, and the lotion, Unilever's Neutral Sensitive Skin, by 34 per cent.
'Affects human health'
'This study has determined that the human oxidation field generated by people exposed to ozone indoors is substantially disrupted when personal care products are worn,' the authors write.
They add: 'Given that the human oxidation field influences the chemical composition of air in the breathing zone and close to the skin, it affects our intake of chemicals, which, in turn, affects human health.'
Experiments found that the ethanol which makes up most perfumes diminishes the cleansing aura by converting the OH radicals into other products quickly and therefore wicks away the cloud.
However, the tested lotion interferes with the cloud by preventing the crucial OH radicals from being made in the first place.
Prof Jonathan Williams, of the Max Planck Institute for Chemistry in Mainz, Germany, co-author of the study, told The Telegraph: 'For both these applications, the result was to actually suppress the OH field, but the suppression seems to occur through two different mechanisms.
'There may be other methods, maybe there's other ways you can influence it, but I think we've shown that, at least in those two cases, it reduces the oxidation field.'
However, he added that it remains unknown whether the diminishing of the chemical body cloud is a health net positive or negative when considering every chemical and environment.
'What we've discovered here is really the phenomenon that there is an oxidation field and it can be manipulated by various forms – at least these two,' Prof Williams said.
'But I really, unfortunately, cannot give a clear message to the public of whether I recommend on a health basis to wear or avoid perfume or lotion because there is not enough information to base a recommendation.'
The scientists found that not all nice smelling chemicals have a significant impact, however.
Linalool, a citrus-scented essential oil which makes up about a third of lavender oil, only reduces the OH cloud by about ten per cent.
'This demonstrates that the ozonolysis of linalool, in the absence of ethanol, may not have a large impact on the OH concentration inside a room,' the scientists said.
The implications for health remain unknown and will be the subject of further research, but previous studies have shown that having a plentiful supply of the chemicals that make up the protective cloud is linked to better airway function, lower inflammation, reduced biological stress, healthier blood vessels and improved blood pressure.
