Release: September 9, 2001

Contact: Kenneth Satterfield(703) 519-1563[email protected]303-228-8460 (9/7-9/12)

INDOOR POLLUTANTS FOUND TO BE A CAUSE OF CHRONIC RHINOSINUSITIS

Common agents found in the home can lead to upper airway inflammation and sinusitis.

Denver, CO -- Chronic rhinosinusitis is one of the most commonly reported disorders in the United States, affecting nearly 15% of the population. The prevalence of rhinosinusitis has risen in the last decade, generating a significant increase of health care costs.

Upper airway infections occur for a variety of reasons. One suggested cause for allergies and recurrent infections of the upper respiratory tract is air pollution. Organic and inorganic pollutants induce inflammatory responses in the upper respiratory tract. Whereas air pollution is suggested to cause allergy and asthma, no data exists in current literature regarding pollution's impact on chronic rhinosinusitis.

Volatile organic compounds (VOC), nitrogen dioxide (NO2) and formaldehyde are common airborne pollutants in the indoor environment that induce airway symptoms and inflammation of various degrees. VOCs include a wide range of individual substances such as alkanes, cycloalkanes, aromatic compounds, hydrocarbons and terpenes, all emitting from various sources in homes (building materials, paint, or consumer products). These compounds have been implicated as causative agents in asthma and building-related illness. For example, indoor levels of NO2 often exceed outdoor levels in homes with gas stoves or kerosene heaters. Exposure to NO2 may cause impaired lung function and increased respiratory infections in young children. Formaldehyde is an important chemical used widely by industry to manufacture building materials. Numerous household products contain formaldehyde in different concentrations.

Although airway obstruction, postnasal drip, allergic sensitization, and increased number of inflammatory cells are common findings in chronic rhinosinusitis, the relationship between indoor pollution and this disorder has not been examined. German researchers have set out to evaluate the exposure to VOCs, NO2 and formaldehyde in chronic rhinosinusitis. To do so, they measured indoor exposure of patients diagnosed with chronic rhinosinusitis and compared the results to corresponding data measured in the homes of patients without chronic rhinosinusitis.

The authors of "Indoor Pollutants and Chronic Airway Inflammation" are Thorsten Jurk, MD, and Michael Damm, MD, both from the Department of Otorhinolaryngology--Head and Neck Surgery, University of Cologne, and Olf Herbarth, MD, from Leipzig, Germany. Their findings were presented at the at the American Academy of Otolaryngology--Head and Neck Surgery Foundation Annual Meeting/OTO EXPO, being held September 9-12, at the Colorado Convention Center, Denver, CO.

Methodology: Eighty-eight patients were included in this study from September 1, 1999 to October 31, 2000 and were assigned into two groups. One with chronic rhinosinusitis (73 patients; 34 females, 39 males; mean age 46.4 years), and the control group without chronic rhinosinusitis (15 patients; 3 females, 12 males; mean age 37.8 years). A detailed history was taken from all patients, including the number of bacterial infections in the upper respiratory tract within the last year, allergic symptoms and smoking habits. Patients also received a thorough ENT examination and allergy-screening tests. Nasal endoscopy and (CT) scans were performed to confirm or exclude chronic rhinosinusitis. Two passive collection systems were installed in the room most frequently used by patients, approximately 1.5 meter above the floor. They were placed away from open windows and potential local sources of indoor pollutants. The Organic Vapor Monitors collected a four-week integrated VOC sample. Diffusion tubes according to "Palmes" were used for the measurement of NO2 and formaldehyde over a five-day period. After air sampling was complete, passive collectors were returned immediately and stored at -30 degrees C until processing.

All analyses were performed with two different polar capillary columns for identification and quantification of 29 individual VOCs (hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, methy-cyclopentane, cyclohexane, methyl-cyclohexane, benzene, toluene, ethylbenzene, m+p-xylene, styrene, o-xylene, 4-ethyltoluene, 3-ethyltoluene, 2-ethyltoluene, naphthalene, chlorbenzene, trichlorethylene, tetrachlorethylene, a-pinene, b-pinene, limonene, (+)-3-carene and (+)-2-carene). Calibration runs were done in the beginning and at the end of each injection sequence by injecting a set of external standards. NO2 was measured by the Saltzmann technique. The Pararosanilin technique was used to measure formaldehyde.

Results: The duration of the sinusitis-related symptoms in the chronic rhinosinusitis-group was 12.4--1.9 years in the mean before presentation in our department. Mean ratings of the severity of the symptoms presented by the patients were rated on 100mm visual analogue scales (VAS). Key findings include:

* The rating for headache and post-nasal drip was 43.1 and 55.0 in the chronic rhinosinusitis-group compared to 32.8 and 32.9 in controls. Hyposmia (a diminished sense of smell) was rated 52.5 by chronic rhinosinusitis-patients and 24.3 by the control group in the VAS.

* Total VOCs (131.5g/m3 (SD--79.7)) were higher in the accommodations of the chronic rhinosinusitis-group than in the control group (115.5g/m3 (SD--50.2)).

* Detailed analyses of the subgroups of VOCs showed increased levels for the mean values of heptane: 5.7 vs. 1.9--g/m3, octane: 3.3 vs. 1.2--g/m3, cyclohexane: 3.6 vs. 1.4--g/m3, methylcyclohexane: 4.9 vs. 1.5--g/m3, 2-Carene: 0.05 vs. 0.02--g/m3 in the chronic rhinosinusitis-group.

* NO2 was 57.3--g/m3 (SD--56.1) in the chronic rhinosinusitis-group and 55.8--g/m3 (SD--37.2) in controls.

* The mean level of formaldehyde was 51.8--g/m3 (SD--48.2) in the chronic rhinosinusitis-group and 68.1--g/m3 (SD--92.6) in the control group. Increased levels of volatile organic compounds (>200--g/m-- were detected in 16.4 percent of the accommodations of the patients suffering from chronic rhinosinusitis).

Conclusion: The researchers believe that this is the first study revealing that patients with chronic rhinosinusitis were exposed to higher levels of volatile organic compounds than healthy subjects. The role of air pollution in the development of chronic rhinosinusitis has been suggested but not evaluated. Profiles of volatile organic compounds in the accommodations of patients with chronic rhinosinusitis were different than those of non-affected volunteers. Although the effects of long-term exposure to indoor pollutants remain not totally understood, VOC can induce airway inflammation even in subtoxic levels. Therefore, the study results indicate that volatile organic compounds are capable of amplifying the inflammatory mucosal disease in chronic rhinosinusitis.

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