Pulmonary and Inflammatory Responses Following Exposure to a Low Concentration of Ozone or Clean Air

Inclusion Criteria:

1. Healthy men and women between 18 and 35 years of age.
2. Physical conditions allowing sustained moderate exercise for 6.6 hours.
3. Normal lung function (NHANES III):
4. FVC > 80 % of that predicted for gender, ethnicity, age and height.
5. FEV1 > 80 % of that predicted for gender, ethnicity, age and height.
6. FEV1/FVC ratio > 80 % of predicted values
7. Oxygen saturation > 94 %.
8. Total symptom Score no greater than 20 (out of a possible 60-see accompanying scoresheet) with a value no greater than 3 for any one score. No more than one score may beequal to 3.

Exclusion Criteria: 1. Individuals with a diagnosis of COVID-19 and/or hospitalized for COVID-19. 2. Individuals who are not "up to date," [meaning a person has received all recommendedCOVID-19 vaccines, including any booster dose(s) when eligible with their COVIDvaccines as defined by the CDC.] 3. A history of acute and chronic cardiovascular disease, chronic respiratory disease,diabetes,rheumatologic diseases, immunodeficiency state. 4. An acute respiratory illness within 4 weeks. 5. Subjects who are asthmatic or have a history of asthma. 6. Allergic to chemical vapors or gases. 7. Any allergic symptoms during the time of participation in the study 8. Female subjects who are currently pregnant, attempting to become pregnant orbreastfeeding 9. Subjects currently taking mega doses of vitamins and supplements,homeopathic/naturopathic medicines or medications which may impact the results of theozone challenge or interfere with any other medications potentially used in the study (to include systemic steroids and beta blockers). Medications not specificallymentioned here may be reviewed by the investigators prior to a subject's inclusion inthe study. 10. Current and past smokers within 2 years, or subjects with a smoking history of atleast a pack of cigarettes a day for more than 10 years over your lifetime. Thisincludes vaping, hookah,and e-cigarettes. 11. Uncontrolled hypertension (> 140 systolic, > 90 diastolic). Blood pressure readingsequal to or greater that 140 Systolic and equal to or greater that 90 diastolic. 12. Subjects who do not understand or speak English 13. Unspecified illnesses, which in the judgment of the investigator might increase therisk associated with ozone inhalation challenge or exercise, will be a basis forexclusion. Temporary exclusion criteria: 1. Individuals who have had an acute respiratory illness within 4 weeks. 2. Individuals who have active allergies. 3. Individuals that have engaged in strenuous exercise within 24 hours of any studyvisit. 4. Individuals unable to avoid drinking alcohol for 24 hours prior to all study visits. 5. Individuals who have been exposed to smoke and fumes for 24 hours before all visits. 6. Individuals that have used an ozone-based home air purifier for 24 hours before allvisits. 7. Individuals that have eaten or drank anything for 2 hours prior to the sputumtraining/screening day visit. 8. Individuals should avoid caffeine for 12 hours prior to all study visits. 9. Individuals should refrain from all over the counter anti-inflammatory agentsincluding those for allergies, and anti-inflammatory drugs or antioxidants for aperiod of one week prior to the train and to the exposure. 10. Individuals that have been exposed to or have consumed any agent or have undertakenany activity within 24 hours of any study visit that the investigators believe maycompromise the results of the study.