Allergies and Air Quality

Guest article by AAH Board Member Brian E. Tison, MD

Vital Allergy and Asthma

Board Certified in Adult and Pediatric Allergy and Immunology


As an allergist here in Houston, daily I watch the effects of air quality on the lives of fellow Houstonians. We know that we live in a region that struggles with air quality, from the Port of Houston, to our reliance on automobiles, to the petrochemical plants, the Greater Houston Region has increased ozone, as well as particulate matter compared to other cities in the region. All of these act as irritants to the nose and eyes, and result in increased inflammation. What this means for us, is that our risk for allergies increases.

Being exposed to ragweed or oak pollen is bad enough, but when combined with diesel exhaust, the effects are compounded. Even for people without allergies, exposure to high levels of irritants along with oak pollen, teaches the body to react to the pollen as well. This is something called the adjuvant effect, which is used to great effect for vaccines, wherein we can teach the body to mount an immune response to something like the polio virus, but it’s not helpful when it comes to ragweed pollen. That’s one of the reasons why for new arrivals to Houston it seems like it’s only a matter of time before they start having allergies like the rest of us. To make matters worse, once your have inflammation from allergies, irritants, such as ozone, or even perfume and cigarette smoke, trigger the same nose and eye symptoms as the pollens do, something called non-allergic rhinoconjunctivitis.

In one of my favorite studies, researches took diesel exhaust particules, captured from light-duty passenger cars, then diluted it in salt water as a nasal rinse. After a nasal wash with these diesel exhaust particles, study subjects then used a nasal spray with a protein they had never been exposed to before (keyhole limpet hemocyancin). If you were one of the subjects with the diesel nasal wash, you had a 50% chance of then becoming allergic to that new protein. In a similar study, if you washed your nose with that same diesel exhaust nasal rinse, then got exposed to ragweed pollen, your allergy levels were 16 times higher compared to ragweed pollen alone.

All of this continues to point to the importance of working on improving the air quality in Houston. So next time you are sneezing and blaming the yellow pollen all over your car, remember that the air quality in Houston set you up for allergies, and that is something we can work on together.