Atmospheric pollution: a danger for the health of your skin.

The synergistic action of environmental pro-oxidants amplifies skin aging.

The skin is the mean interface between our body and the external environment. It acts as a biological barrier against a range of chemicals and physical environmental pollutants. It is defined as the first defense against the environment because of its constant exposure to oxidants, including ultraviolet (UV, UVA, UVB), infrared (IR), visible light (VL) and other environmental pollutants such as fine particles, diesel and domestic exhaust gases and fossil fuel combustion gases (fuel oil, coal, diesel...), cigarette smoke (CS), halogenated hydrocarbons, heavy metals and ozone (O3).

 Exposure to environmental prooxidants induces the formation of reactive oxygen species (ROS) and the generation of bioactive molecules that damage the cells of the skin (1). In China, the number of hospital visits for skin problems specially increase during episodes of atmospheric ozone pollution (2). A recent clinical study showed that pollution aggravates atopic dermatitis, with Ultra-Fine Particles (PUF or UFP) that are suspected of exacerbating the inflammation phenomenon. 

In Caucasian-type women over 70 (3), exposure to pollution correlates with signs of skin aging such as brown spots and wrinkles. Although the mechanisms of the effects of pollution on the skin are not yet well known, the different components of pollution have been studied to understand their very harmful effects (4)

The different atmospheric pollutants.

The term “pollution” is usually emploied, but it globalises the large number of compounds it contains. It is composed of air pollutants from exhaust gases (CO, SO2, hydrocarbons), combustion-related emissions (NO2), ozone formed from pollutants transformed by UV rays. Pollution alsp contains solid particles, and those smaller than 2.5 micrometers are likely to reach the alveoli of the lungs and the smallest cutaneous corners such as pores.

The main pollutants in the atmosphere can be divided into two groups: gases and solid particles (dust, fumes). It is estimated that gases account for 90% of the total mass of pollutants released into the air and particles the remaining 10%. 

Air pollution is the result of many factors: energy production, intensive agriculture, extractive, metallurgical and chemical industries, road and air traffic, incineration of household waste and industrial waste, etc. ...

The pollutants of the atmosphere act at different scales: some gaseous compounds have no effect locally but can disrupt the global climatic balance, while others are particularly virulent for local and regional health but have a very limited influence on the atmosphere as a whole.

Air pollution is most prevalent in urbanized and industrialized areas, not only because of the concentration of industries and domestic households, but also because of the movement of motor vehicles. The spread of large cities has as a corollary transport needs ever more numerous. There is also the burning of tropical vegetation from slash-and-burn agriculture that releases soot, carbon dioxide, carbon monoxide, hydrocarbons, nitric oxide and nitrogen dioxide.

This pollution remains one of the most important. Pollution is therefore a multiple phenomenon and complex to comprehend in its entirety.

Air pollutants and their impacts on the skin. 

Clinical manifestations of pollution on our skin.

Exposure to an atmosphere laden with ozone and pollutants generates oxidative stress, with an outbreak of free radicals and a reduction in the level of key cutaneous antioxidants such as vitamin E and vitamin C (6).

Overall, the effects of long-term exposure to intensive pollution is manifested in vivo by a loss of radiance, a drop in skin hydration, the eruption of redness or acne and especially premature aging.

Studies showed that women living in urban areas have deeper wrinkles and more pigment spots on their faces than women living in the countryside (7). 

The pollution would cause an over-secretion of sebum (8), making the skin more oily and prone to imperfections, making the complexion duller, causing premature aging of the skin with deeper wrinkles, more pigment spots and sagging skin (9). The cocktail effect of pollutants attack the membranes of our skin cells making them more reactive and sensitive, which increases the risk of developing eczema, dermatitis or psoriasis. 

Solutions to fight against the effects of pollution.

The cleansing ritual of the skin is an essential element to keep skin healthy. The urban lifestyle tends to disrupt the essential functions of our skin, making it more oily, dull and easily prone to imperfections. First, it is crucial to clean the skin thoroughly to remove particles and debris that settle on our skin, before applying any other care.

 Thus the action of pollutants on the skin must be neutralized and our cells need to be protected from oxidative stress. At Alphascience, we have worked on combinations of actives that will act on most pollutants, their synergistic action with UV and oxidative stress:

• L-ascorbic Acid: limits damage to UV-related cell DNA (10). It is a powerful antioxidant.
• Phytic Acid: regulates deregulation of sebum due to pollution (11), transforms metals into inert salt (12), neutralizes the effect of PAH, regulates the production of melanin.
• Tannic Acid: a chelator of metals (13), acts in synergy with vitamin C and enhances its antioxidant activity by inhibiting the Fenton reaction (14).
• Ginkgo biloba: improves the irrigation of tissues to improve the radiance of the complexion, to offset the effects of carbon monoxide.
• Ferulic Acid: repairs cellular damage related to UV and pollution (15).

These actives are also powerful antioxidants that act in synergy to neutralize the oxidative stress associated with the combination of UV and pollution. To go further, it is necessary to measure the impact at the cellular skin level of the combination of UV and pollution, as well as the effectiveness of the assets. Alphascience's scientific teams are developing a novel clinical study on these topics. 

The author: Alfred MARCHAL, PhD in organic chemistry and MBA, is an internationally- recognized antioxidants and aesthetic medicine expert. He has 35-year academic experience in R&D for pharmaceutical organic synthesis and phyto pharmaceuticals. Author of many scientific articles and patents in particular for vitamin C, vitamin K and hyaluronic acid. He runs ALPHASCIENCE Research Department and is board member in pharmaceutical companies.  

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