With rapid industrialisation in the 18th and 19th centuries came air pollution, and things have only gone from bad to worse in the 21st century. Outdoor (ambient) air pollution has been a rising concern in countries across the world – in both developing as well as developed nations. A recent study by the World Health Organisation (WHO) measured air quality in nearly 1,600 cities in 91 countries and found that 90% of the people in urban areas breathe in polluted air. Many cities were found to have breached the safety guidelines for air pollution for the period 2008-2013. Shockingly, 9 English cities and town have been listed as violators, including London, Birmingham, Nottingham and Southampton. Apart from domestic and commercial heating systems, road traffic is the number one contributor to air pollution levels.
Air pollution refers to the presence of harmful substances in the air that we breathe. These include various poisonous gases, particulate matter, biological material and other harmful substances that harm human health as well as that of plants and animals. Nitrogen dioxide, sulphur dioxide, carbon monoxide and suspended particulate matter are the most common pollutants. The UK AIR Quality Standards Regulations has set permissible limits for these pollutants, yet some of them have been exceeding prescribed levels, especially nitrogen dioxide and particulate matter. Long-term exposure to air pollution has contributed to more than 28,000 deaths across the UK in 2010, according to Public Health England (PHE). The WHO goes as far as calling air pollution “the single largest environmental health risk”.
Impact on Health
The adverse health effects of air pollution have been well documented. According to the WHO, a staggering 7 million deaths (in 2012) can be directly attributed to air pollution – both outdoor and indoor. Respiratory infections and pneumonia are the most common health issues as are chronic pulmonary diseases such as bronchitis and asthma. Long-term exposure to particulate matter has also been found to be a risk factor for cancer and cardiovascular disease.
Air pollution can lead to dry eye syndrome in which the cornea and conjunctiva (lining inside the eyelids) become inflamed. This makes the eyes itchy and tired and also causes them to burn. It not only causes discomfort but can also make the eyes sensitive to bright light. It can also lead to conjunctivitis. Hydrogen sulphate in the air also affects the anterior chamber of the eyeball – the fluid-filled space between the iris and the cornea. When hydrogen sulphate comes in contact with the fluid (called as aqueous humour), it can cause dizziness, even blindness in extreme cases. Another air pollutant is CFC or chlorofluorocarbons emitted by air conditioners, refrigerators and aerosol sprays, which lead to depletion of the ozone layer. This then allows harmful ultraviolet rays to reach the earth, which can damage the eyes (and also cause skin cancer by prolonged exposure).
What you can do
It is impossible to completely avoid air pollutants. However, here are some tips for protecting yourself:
- Avoid stepping out between noon and 4 p.m. as air quality is lowest when the temperature is highest.
- Avoid walking or biking along busy streets.
- Get a home air filter that blocks out particulate matter.
- Shield your eyes when you step outside by wearing sunglasses that offer adequate UV protection.
Make sure that you get your eyes tested regularly, not to only to check if your prescription has changed but also to check your ocular health. Drop by at your local Leightons Opticians branch for a free eye examination; or book an appointment online.