By August 11, 2020 No Comments

POLLUTION IS EVERYWHERE. It is defined as contamination of the earth’s environment with materials that interfere with human health, quality of life and natural functioning of the ecosystem.  These environmental aggressors can break down the barrier function of the skin and constantly change the skin biome.  We are talking about air pollution, light pollution, UV pollution, and soil pollution. The World Health Organization defines air pollution as contamination of the indoor and outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere.

Often when we see changes to the skin, we consider every other cause accept pollution.


Exhaust fumes, factories and the manufacturing processes, chemical and petroleum refineries, cigarette smoke, candle burning, wood fires and gas fires, volcanic eruptions, fires, biological decay, radioactive materials, all release gases or particles into the air – and there are many more. All these polluted gases create a change to the biome of the skin triggering a cascade of damage to the skin’s surface.

Air pollutants exist as solids, liquids, gases and particulate matter. All of these can be absorbed directly through the skin into the subcutaneous tissue, or via hair follicles and sweat glands.

Our skin is a barrier to the outside world and is exposed to all of these pollutants. It acts as a physical, chemical and an immunological barrier against environmental factors so,  when the skin is broken we become very ill.

Oxidative stress that is caused by pollution reduces the skin’s antioxidant defenses, depleting enzymatic and non-enzymatic antioxidant capacity.  Enzymatic antioxidants include glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase. Non-enzymatic antioxidants include vitamin E, vitamin C and glutathione.

The reduction in the skin’s anti-oxidant defense increases free radicals and reactive oxygen species which breaks down the lipid plasma membrane. This is known as lipid peroxidation.

There is a huge cascade from this with reactive oxygen species stimulating the release of pro-inflammatory mediators. The release of these mediators causes accumulation of neutrophils cells and other phagocytic cells that increase free radicals and this becomes a vicious cycle.


Particulate matter is extremely small – in fact, small enough to enter a follicle. It then becomes trapped in the follicle where it continues to cause damage to the skin. Particulate matter is caused by refuse incinerators, automobile, construction activities, bush fires and natural wind-blown dust. It creates detrimental effects through oxidative stress, contributing to extrinsic ageing. Pigmentation, increased nasolabial folds, solar elastosis and telangiectasia. Excessive road traffic is the harshest and the most harmful components of particulate matter. Think of your clients that work close to busy roads or work with road works.

PM2.5, these are small particles that pass through the nose, throat, lungs and into the blood stream.

While PM10 are very small particles that pass through the nose, the throat and then the lungs. They can have a huge impact not only to the lungs, but also the heart, creating complications to the entire health of the body including the skin.


Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread organic pollutants. The source of this pollution is from firewood or wood-burning, automobile exhaust fumes especially diesel engines and all smoke, resulting from combustion (including cigarette smoke and candle smoke).  PAHs are converted into quinines, redox-cycling chemicals that produce reactive oxygen species.

The long-term exposure to PAHs increases trans-epidermal absorption of this pollutant as well as entering the follicle.

PAHs increase melanocyte proliferation thus increasing pigmentation lesions.  They have also been implicated in the development of skin cancers.  They have horrid ability to break down the fat barrier in the stratum cornuem layer, this really does disturb the skin’s biome.  Complications that can occur from this are obviously, extrinsic ageing, skin rashes, eczema, dermatitis, acne and we have already mentioned pigmentation.

Nitrogen oxides are emitted mainly from mobile and stationary combustion sources. They cause oxidative damage therefore increasing free radicals that may oxidize amino acids in tissue proteins, which increases lipid peroxidation. This in turn increases trans-epidermal-water-loss just consider the changes to the skin when we have fast trans-epidermal water loss.

Atmospheric sulfur dioxide generates from fuel combustion and power generation, as well as natural sources (volcanic activity and bush fires).   Exposure to these types of pollutants increase cytokines in keratinocyte cells that can cause atopic dermatitis and eczema.

Carbon Monoxide (CO) is and odourless, colourless gas. It is formed when the carbon does not completely burn and it is at its highest during cooler weather.  Cold temperatures interfere with combustion where it is not completed, trapping pollutants close to the ground.  High levels affect the lungs, heart and brain.  Whenever there is a problem with the lungs, there is a high risk of developing the skin disorder sacoidosis.


This is known as a physical pollutant and affects ultraviolet wave lengths.  UV is absorbed by the ozone layer and oxygen in the atmosphere.  Sadly, there is a huge depletion of the ozone caused by photochemical smog and refrigerant gases. This increases the penetration of ultraviolet wavelengths to ground level. We are already dealing with and seeing the affects of UV A and B on the skin. An increase will create further extrinsic ageing to the skin.

As you can see environmental pollution comes in multiple forms, so here are some things we need to look out for are:

  • PAHs – Polycyclic aromatic hydrocarbons
  • VOCs – Volatile organic compounds 
  • NOx – heavy metals, nitrogen oxides 
  • PM – particulate matter
  • PM 2.5 – ozone and cigarette smoke, which is prevalent in smog, this is too large to penetrate the skin, but causes major damage to the skin’s biome
  • UVR – ultraviolet radiation


Please don’t be misled to think if you stay indoors you are free of pollution.  YOU ARE NOT! Indoor pollution poses as much risk as out door pollution does.

Consider indoor pollution, such as Nitrogen Dioxide (NO2), which is released from cooking gas, as well as cigarette smoke.

Another serious indoor pollutant is mold and pollen. If mold spores are inhaled, the complications can be very serious, causing allergic reactions or asthma attacks. Skin irritation and infection can be quite severe from inhaling or touching mold.

Apart from the indoor air pollution that is created, dwellings that have inadequate ventilation pose a huge problem for pollution. There are many household products and pesticides that cause indoor pollution. When thinking about air pollution be aware of the air in homes, offices and other work areas, not to mention public transport – the list will never end.


Skin is the largest organ of the human body and any factor affecting skin health will impact the whole body. Air pollution is everywhere and does not discriminate as to where you live, it will change how your skin feels, looks and ages.

During the consultation process it is important to identify pollution and types of pollution that the client is, or has been exposed to. The presence of atopic dermatitis and eczema has been increasing over the years in Asian and European countries. Studies are showing that people who live in highly polluted areas are at risk of developing these skin disorders.  Heat waves have made the air in our cities lethargic causing pollutants to swirl into smog. It might only be temporary at times, but it does impact on our skin and our health. Remember the skin’s biome is affected by pollution, research has revealed how ongoing, daily exposure to pollution dramatically impacts the skin’s health and appearance.

To further enhance your knowledge and understanding of the skin and the various factors that contribute to skin health please consider Gay Wardle’s

Gay Wardle’s

Advanced Skin Analysis training.  Visit


Gay Wardle

Gay Wardle

Gay Wardle is one of Australia’s leading industry experts in skin analysis, anatomy and physiology.