Pollution is the invisible enemy of human beings surrounding us and generating detrimental effects to our skin. Pollution is a mixture of chemical components introduced into the atmosphere and emitted from both man-made and natural sources affecting the air quality which results in harmful consequences on human health. Some air pollutants include ultraviolet radiation (UVR), cigarette smoke, polycyclic aromatic hydrocarbons, particulate matter, volatile organic compounds, and nitrogen oxides.
The skin is the largest organ of the body, and it comprises essentially a protective function by acting as the first physical, chemical, and immunological barrier against external agents. Simultaneously, the human skin is constantly exposed to environmental stressors such as pollution that severely impact the skin structure by triggering various molecular processes, including oxidative stress and inhibition of antioxidant mechanisms leading to aged skin appearance. So thus, pollution is an extrinsic factor involved in the ageing process and its phenotypic effects in the skin can even appear after a long time of exposure.
Nowadays, people are excessively daily exposed to air pollutants not only outdoor due to industry- and traffic-derived air pollution, but also indoors from domestic activities like cooking, heating, house cleaning, and light exposure (screens). Pollutants can penetrate the skin by dermal uptake based on their size and chemical composition driving to the skin barrier function deterioration, and the redox balance. The underlying mechanism by which each pollutant toxically acts in the skin depends on its specific physicochemical characteristics, and the pathways may be diverse.
Consequences in the skin due to pollution
As it was mentioned above, pollution plays an important role in extrinsic ageing. The alterations in the skin structure and in their constitutive proteins and components promote and accelerate premature ageing, making visible signs of cutaneous ageing mainly in the face, in particular pigment spots and coarse wrinkles. Probably the most well-studied and dangerous pollutant is the cigarette smoke since it can produce a large number of effects in the skin, to illustrate, oxidative stress, inhibition of antioxidant mechanisms, increase the transepidermal water loss, degeneration of the connective tissue in the skin, and degradation of collagen and elastin fibres. Inflammatory skin disorders such as atopic dermatitis, eczema and psoriasis may be provoked or their symptoms might be exacerbated, as well as the increased risk of acne and skin cancer. Not to mention that photoaging is the major effect of the UVR exposure in the skin and in combination with particulate matter might have negative synergistic effects increasing the facial pigmentation.
Strategies to mitigate the impact of pollution in the skin
To protect yourself from the detrimental effects of pollution, it is advisable the daily use of rinse-off products to clean off the face surface, sunscreen to block UVR exposure, products to moisturize the skin, as well as of products containing antioxidants.
All in all, the population is increasingly exposed to air pollution generated by a plethora of sources, which considerably affects the skin structure potentiating skin ageing through different pathways. Even though pollution is microscopic and difficult to identify its levels in the air, and its effects have an impact on our skin, it is important to prevent damage from this invisible enemy. Nevertheless, new research and development activities are currently ongoing to offer alternative and innovative products designed to improve the care and protection of the skin or even hair against pollutants. This poses the question what happens to the hair also directly affected by pollutants?
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REFERENCES
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