Hay fever and air pollution

Hay Fever

What is hay fever?

It is estimated that up to 15% of Australians have hay fever. Interestingly hay fever is not caused by hay and it is not a fever. The medical term for hay fever is 'allergic rhinitis' or literally an allergic reaction causing inflammation of the nose. It is in fact caused by an allergic reaction to airborne particles, typically floating plant material such as pollen, often from grasses and trees, although hay fever can be caused by other particles as well, such as dust, dust mites, miniscule particles of hair and skin (dander) and mould spores
If you have hay fever your nasal passages swell when particles you are allergic to are breathed in through the nose, and this swelling can spread to the back of the throat and the mouth. You may also have symptoms such as a runny or blocked nose, sneezing and itchy watery eyes. Hay fever is also linked to disturbed sleep, fatigue, headaches and frequent ear/sinus problems. It is also associated with asthma.

How is hay fever treated?

Medical treatment for hay fever is only recommended when associated with troublesome symptoms impacting daily life. The following treatments may be recommended...

  • Antihistamines/saline decongestant nasal sprays - these control the symptoms of hay fever
  • Steroids - as a nasal spray
  • Allergen immunotherapy - a type of treatment where the body's natural reaction to an identified allergen is reduced over time (this can be 3-5 years)

Air Pollution

Air pollution is now recognised as detrimental to respiratory health and a major cause of serious lung conditions. It is estimated that over 40,000 people in the UK die each year due to respiratory diseases caused by air pollution, particularly exhaust fumes from diesel engines which contain particulate matter and high concentrations of other pollutants.

When the US city of Atlanta hosted the Olympic Games in 1996 they introduced a rapid transit system and a bus fleet both of which ran on natural gas instead of diesel. Asthma attacks in the city decreased by 44% and ozone reduced by 28%.

What causes air pollution?

Any industrial process causes a degree of air pollution, but transport systems, since they are in very close proximity to people, cause the greatest air pollution problems. The primary pollutants that affect respiratory function are...

  • Carbon monoxide (CO) - carbon monoxide is linked to traffic pollution and cars and other vehicles are responsible for over half of all CO emission. Industrial processes, cigarette smoke and gas heating give off CO
  • Lead - largely removed from petrol, it is still emitted by some industrial processes
  • Nitrogen dioxide (NO2) - Nitrogen dioxide aggravates lung conditions such as emphysema/chronic bronchitis and heart disease
  • Ozone - ozone is created when sunlight interacts with particulate matter and produces smog
  • Particulate matter - a mix of miniscule particles and liquids in the atmosphere
  • Sulfur dioxide - emitted when some fuels are burned is a harmful pollutant

How can you avoid being affected by air pollution?

It is almost impossible to avoid pollution in some places, such as major cities, however there are some steps you can take to reduce the effect of pollution on your (and your family's) respiratory health...

  • Limit time in your vehicle
  • Stay indoors during the heat of the day
  • Avoid exercising eg riding a bike or running in or near congested traffic
  • Exercise outside in the mornings when air pollution is less severe
  • If possible avoid living within 150m of a major road
  • Listen out for air quality alerts and follow the instructions given (which are generally to stay indoors and close all windows and doors)
  • Install HEPA filters in your home (these filter out air particles)

Eat a good diet (fish oil and vitamin C may reverse damage caused by airborne pollutants)