Increasingly poor air quality and rising smog greatly affect almost every part of the human body, including the eyes. The toxins in the air we breathe in include noxious gases, pollutants and dust particles. These harmful contaminants cause a number of health problems, including acute impact on the eyes, as seen frequently in the smog season by experts like Eye Specialist in Karachi. Read on to know more about smog, and its effect on the eyes:

What is smog?

The word smog is a compound form of ‘fog’ and ‘smoke’, defined first in 1905, to describe the poor air quality of many British towns. Smog in the air forms due to emissions and air pollutants from industries, factories, cars, power plants and ground level ozone. This visible form of polluted air contains harmful chemicals like hydrocarbons, sulphur dioxide, nitrous oxides and volatile organic compounds (VOC).

Several respiratory, cardiovascular and neurological disorders are attributed to the inhalation of these deleterious toxins in the air. These effects are linked to the time of exposure, air quality of the region and the person’s own health and age. However, pregnant women and children are particularly susceptible to the effects of smog.

The health effects of smog include respiratory illness due to inhalation, such as asthma, bronchitis, persistent cough, along with neurological and cardiovascular disorders. Additionally, smog can contribute to cancers, and in pregnant women it can cause increased incidence of miscarriage, low birth weight babies and poor infant health. Eye, skin and tracheal irritation are some other acute effects of smog. In the long-term, smog can even cause genetic mutations.

What are the immediate effects of smog on the eyes?

Exposure to smog increases the patient load in terms of eye diseases. This is because of the immediate effects of smog which can include:

• Redness of the eyes
• Acute onset of conjunctivitis
• Watering in the eyes
• Dryness of eyes
• Sticking of the eyelids
• Burning and stinging of the eyes due to the chemicals in the air
• Blurring of vision
• Sensitivity to light exposure
• Mucus plugs in and around the eyes

How does smog affect eyes in the long-term?

There are several ways in which smog can affect the eyes in the long run and make simple everyday tasks difficult:

• Straining of the eyes: most people impacted by smog, strain their eyes during daily activities. Simple tasks like driving or reading can become tedious if one is exposed to smog for long. Needless to say, with longer exposure to poor quality air, there is more irritation of the eyes.
• Tear film instability: Excessive exposure to smog can dry out the eyes by impacting the tear film. This in turn leads to itching, irritation and watering of the eyes in addition to susceptibility to eye infections. The latter is a result of tear film instability, the function of which is to form a protective shield from infections.
• Effect on cornea: Extreme dryness can even affect the surface of cornea, the transparent layer in front of the iris. The transparent medium of cornea is responsible for refraction of light, and thus image formation on the retina. If the cornea is affected, it can lead to vision problems in the future.

How to protect the eyes from the impact of smog?

Following exposure to smog, minor symptoms like redness, dryness and irritation are common. However, these symptoms should not be ignored especially if they persist. The ill effects of smog can be mitigated through the following measures:

• Staying indoors: during the worst of the smog hours, it is a better idea to limit exposure to the poor air and staying indoors. Early mornings are one of the peak smog hours, and it is easier on the eyes to not go out at this time.
• Limiting the use of contact lenses: in case of redness and irritation in the eyes, it is not a good idea to wear contact lenses. They can increase the discomfort in the eyes.
• Using lubricating eye drops: to mitigate the dryness in the eyes, experts can prescribe lubricating eye drops that keep the eyes moist and the tear film stable.