How Pollution Dries Your Skin

Our skin is the largest organ in the body and is susceptible to environmental stressors. Pollution is a growing threat to human health worldwide, and skin is one of the main targets of pollutants. These pollutants can infiltrate the deeper layers of the epidermis, causing inflammation, dehydration, and a cellular-level reaction that leads to lost elasticity and firmness. This can result in skin pigmentation problems, an uneven skin tone, and dullness, as well as the formation of wrinkles and fine lines – all signs of premature skin ageing. People with sensitive skin or inflammatory skin diseases such as eczema, rosacea, and psoriasis are more susceptible to the effects of pollution.

Air pollution can cause dehydration and dryness

Our skin is the largest organ in the body, and our surroundings have a significant impact on its health. From UV rays to climate and weather, our skin is susceptible to environmental stressors and damage that we may not even be aware of.

Air pollution is one of the most prominent environmental aggressors when it comes to skin health. Pollution particles are often tiny—sometimes 20 times smaller than pores—allowing them to infiltrate the deeper layers of the epidermis. These particles can cause oxidative stress, which weakens the skin's barrier and triggers inflammation. This can result in pigmentation problems, an uneven skin tone, and the formation of wrinkles—all signs of premature skin ageing.

Airborne pollutants can also increase trans-epidermal water loss (TEWL) and compromise the epidermal barrier function and structural integrity of the skin. This can induce or exacerbate various skin diseases, especially in those with pre-existing inflammatory skin conditions such as eczema, rosacea, or psoriasis. The damage to the skin's natural protective barrier caused by pollution particles can lead to increased water evaporation from the skin, resulting in dryness and dehydration.

Additionally, air pollution exposure can create free radicals, highly unstable molecules that cause damage by stealing electrons from healthy skin cells. This process can lead to collagen breakdown, hyperpigmentation, and fine lines. Free radicals can also increase inflammation, making acne and other inflammatory skin conditions worse.

To combat the effects of air pollution on the skin, it is essential to incorporate protective and hydrating skincare ingredients. Antioxidants, for example, can neutralise free radicals and diminish their damaging effects. Vegetable squalane, found in certain skincare products, can help to soothe, nourish, and protect sensitive skin.

Pollution particles penetrate skin layers

The skin is the largest organ in the body and is susceptible to environmental stressors and damage. Pollution particles can penetrate the skin's layers and cause oxidative stress, which can weaken the skin's barrier and trigger inflammation. This can result in skin pigmentation problems, an uneven skin tone, and dullness, as well as the formation of wrinkles and fine lines—all signs of premature skin ageing.

The size of pollution particles is sometimes as many as 20 times smaller than pores, allowing them to infiltrate the deeper layers of the epidermis. The transdermal penetration of solid particles depends on their size and shape, as well as the state of the skin barrier. Nanoparticles larger than 45 nm cannot penetrate the skin. Ultrafine particular matter (UFPM) with a size between 21 and 45 nm can only penetrate and permeate skin with an impaired barrier, whereas smaller 4–20 nm nanoparticles can permeate both damaged and intact skin.

Particulate matter (PM) is among the most harmful pollutants, composed of very small particles and liquid droplets containing organic chemicals, acids, and other toxic chemicals. These particles originate from heating, industrial emissions, and road traffic, especially diesel engines. When pollution particles enter the skin, they create free radicals, highly unstable molecules that bounce around in the skin, seeking to steal electrons from healthy cells, thereby injuring them.

The effects of pollution on the skin are well documented. A study in Beijing found that those living in highly polluted districts had significantly worse skin hydration and lower levels of important biomarkers indicating a compromised skin barrier function. Another study in Shanghai observed oxidative stress responses in human skin cells exposed to concentrated air particles. Clinical evidence also suggests a correlation between exposure to air pollutants and the aggravation of symptoms of chronic immunological skin diseases.

To protect the skin from pollution particles, it is essential to use skincare products that can help shield the skin and repair its barrier function.

Oxidative stress and inflammation

Skin, as the body's first line of defence, is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the body's antioxidant system fails to eliminate ROS, oxidative stress is initiated, which results in skin inflammation, cellular senescence, and cancer.

Oxidative stress is caused by a variety of factors, including solar ultraviolet, infrared and visible light, and environmental pollution, such as ozone and particulate matter. Skin microbiota also play an important role in skin quality, and their composition is influenced by pollutants and UV exposure.

Several studies have confirmed the association between cutaneous microbiota composition and pollution exposure levels. For example, He et al. observed that the skin microflora of the forearm of 20 women was almost halved after exposure to atmospheric-equivalent O3 levels for 2 hours. Similarly, Krutmann et al. reviewed three Asian studies that suggested a link between elevated levels of airborne pollutants and a higher prevalence of acne.

Oxidative stress can lead to skin inflammation through two main mechanisms. Firstly, ROS directly damage biological macromolecules, including proteins, DNA, and lipids, which are essential for cell metabolism, survival, and genetics. This damage causes oxidative stress-induced inflammatory skin conditions such as psoriasis and dermatitis. Secondly, ROS mediate cellular signaling pathways, altering the expression of genes involved in inflammatory responses.

The impact of pollution on skin health is significant. Clinical studies have shown that individuals living in highly polluted areas have worse skin hydration and compromised skin barrier function compared to those in less polluted areas. Pollution particles can penetrate the deeper layers of the epidermis, causing inflammation, dehydration, and a cellular-level reaction that leads to lost elasticity and firmness.

Therefore, it is essential to protect the skin from the adverse effects of pollution through the use of skincare products that contain antioxidants and other protective ingredients.

Premature skin ageing

As the body's largest organ, the skin is susceptible to environmental stressors and damage. Pollution can cause oxidative stress, which weakens the skin's barrier and triggers inflammation, pigmentation problems, and dullness. This can lead to premature skin ageing, with the appearance of fine lines, wrinkles, and uneven skin tone.

A study by Olay UK compared the skin health and appearance of over 200 women in Beijing's least and most polluted districts. The results showed that those in the highly polluted district had significantly worse skin hydration and lower levels of important biomarkers indicating a compromised skin barrier function.

The skin's exposure to pollution can create free radicals, unstable molecules that damage healthy cells and collagen, leading to a loss of firmness and the formation of fine lines and wrinkles. This process can be combated with antioxidants, which neutralise the effects of free radicals.

Additionally, pollution can exacerbate inflammatory skin diseases such as eczema, rosacea, and psoriasis. It can also cause skin dehydration due to damage to the skin's natural protective barrier, leading to further dryness.

To protect against the effects of pollution, skincare routines should incorporate ingredients that fight pollution and build the skin's barrier, such as vegetable squalane and clary sage extract. Antioxidant serums, such as those containing turmeric, can also help strengthen the skin's resistance and limit the appearance of ageing.

Skin diseases and conditions

Skin is the body's first line of defence against harmful environmental factors, and it is constantly exposed to a mixture of air pollutants. These pollutants can enter the skin in two ways: directly, through transcutaneous absorption, and indirectly, through systemic distribution after inhalation or ingestion.

When pollution particles enter the skin, they can cause oxidative stress, which can weaken the skin's barrier and trigger inflammation. This can lead to skin pigmentation problems, an uneven skin tone, and dullness, as well as the formation of wrinkles and fine lines—all signs of premature skin ageing.

People with sensitive skin or inflammatory skin diseases such as eczema, rosacea, and psoriasis are more susceptible to the effects of air pollution as their skin barrier is already compromised. Pollution can also exacerbate inflammatory skin diseases and other skin conditions such as acne.

To protect the skin from the harmful effects of pollution, it is important to use skincare products that contain hydrating and soothing ingredients, such as vegetable squalane and clary sage extract. Antioxidants are also key, as they can neutralise the free radicals created by pollution and prevent DNA damage and cell mutation. In addition to skincare, protective clothing and barrier creams can help shield the skin from pollution particles.

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