Ozone Levels Linked to Allergy Symptoms
Recent research may explain why some people allergic to pollen have allergy symptoms during times outside the pollen season. Pollen allergies are also apparently linked to levels of ozone in the air.
Grass pollen allergies studied
The researchers, faculty scientists from the Macedonia University Clinic of Pulmonology and Allergy, conducted a randomized, double-blind clinical trial with 10 people who were allergic to grass pollen.
The patients were exposed to two hours of filtered air, as well as air with high ozone levels – 400 parts per billion – on two separate occasions. These tests were conducted prior to the pollen season and after the pollen season.
The tests reproduced environmental conditions for two hours for each test. The researchers measured the patients’ nasal levels of histamine, eosinophil cationic protein, myeloperoxidase, total proteins, and albumin. They also measured levels of immune cells such as neutrophils and eosinophils from the nasal discharge. These allowed the researchers to determine whether the patients were having an allergic response to the environmental conditions set up by the test.
In each of the tests – both in pollen season and outside of pollen season – the patients responded greater to the higher ozone levels – as if they were having an allergic response to the higher ozone levels. As these responses were compared to the filtered air responses, it became evident that for those will allergies, higher ozone levels can exacerbate conditions just as high pollen levels can.
The researchers also found that the six-hour allergic response after higher ozone exposure produced a sustained increased allergic response – as compared with those who were breathing the filtered air.
The researchers found that neutrophil levels within nasal discharge was significantly higher among those breathing the higher ozone air. Eosinophils were also significantly increased. Because these elements are directly related to an immune system response, the researchers concluded that not only can higher ozone levels increase allergic response, but that the increased level of sensitivity among the nasal tissues in those who have allergies leads to a greater allergic response to ozone.
The Dangers of Ozone and how it is produced
High levels of low level ozone – ozone within our breathing atmosphere – has becoming increasingly concerning to health experts, and has been related to higher rates of asthma and even cardiac arrhythmia. Lower-level ozone is produced when pollutants – from cars, manufacturing and so on – become exposed to sunlight. Volatile organic compounds (VOCs), carbon monoxide and other oxides become degraded by sunlight and the reaction produces ozone.
According to a 2007 American Lung Association State of the Air report, 46% or about 136 million Americans live within a county having “unhealthful” levels of either ozone or particle-based outdoor pollution. Over 38 million Americans live in a county with “unhealthful” levels of both ozone and particle pollution. A third of Americans live in “unhealthful” ozone level counties.
Hay fever and allergies related to exposure via breathing are technically called allergic rhinitis. Pollen-related allergies are called seasonal allergic rhinitis. Increasingly, doctors are seeing pollen allergy sufferers having symptoms long after pollen season is over.
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