Cardiopulmonary Responses to Exposure to Ozone and Diesel Exhaust (DEPOZ)
Cardiopulmonary Responses to Exposure to Ozone and Diesel Exhaust With Moderate Exercise in Healthy Adults
Descripción general del estudio
Estado
Condiciones
Intervención / Tratamiento
Descripción detallada
Numerous epidemiological studies have demonstrated an association between acute and chronic exposure to air pollution and various adverse cardiopulmonary effects including mortality, respiratory tract infections, exacerbation of asthma symptoms, chronic bronchitis, ischemic heart disease, and stroke [1] and other health effects. Understanding the components responsible for these effects is difficult because ambient air pollution is a complex mixture of gases and particulate matter (PM). In this complex mixture of ambient air pollution, ozone (O3) and diesel exhaust (DE) are generally major and important components. Controlled exposure of volunteers to either pollutant have resulted in biological effects such as lung physiological changes. However it is not known if co-exposure to both pollutants, similar to polluted ambient air, can induce additive or synergistic effects. Additionally it is also uncertain if exposure to DE, or DE with O3, can alter a subsequent exposure to O3 similar to multiple day exposures that the general population receives. This study proposes to examine whether co-exposures to O3 and DE can induce additive or synergistic effects, and whether a previous DE exposure alters a response upon subsequent exposure to O3. The potential effects of O3 on cardiac electrophysiology are also not clear.
Approximately 15 healthy non-smoking volunteers between the ages of 18 and 55 will be exposed in a controlled manner to O3 (approximately mean concentration of 0.3 ppm over the 2 hr exposure period), or diesel exhaust (DE; ~300 µg/m3), or a combined O3 and DE exposure while undergoing moderate intermittent exercise at the EPA Human Studies Facility. A clean air exposure will serve as a control. Primary endpoints for evaluating health effects and surrogate responses are changes in lung function and heart rate variability. In addition, other cardiopulmonary and vascular biological endpoints will be measured, as well as markers of exposure and genetic markers of susceptibility.
Tipo de estudio
Inscripción (Actual)
Fase
- No aplica
Contactos y Ubicaciones
Ubicaciones de estudio
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North Carolina
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Chapel Hill, North Carolina, Estados Unidos, 27514
- US EPA Human Studies Facility
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Criterios de participación
Criterio de elegibilidad
Edades elegibles para estudiar
Acepta Voluntarios Saludables
Géneros elegibles para el estudio
Descripción
Inclusion Criteria:
- Healthy men and women between 18 and 55 years of age
- Physical conditioning allowing intermittent, moderate exercise for 2 hours
Normal lung function:
- FVC > 75 % of that predicted for gender, ethnicity, age and height.
- FEV1 > 75 % of that predicted for gender, ethnicity, age and height.
- FEV1/FVC ratio > 75 % of predicted values.
- Oxygen saturation > 96 %.
Exclusion Criteria:
- A history of acute and chronic cardiovascular disease, chronic respiratory disease, diabetes, rheumatologic diseases, immunodeficiency state, and acute respiratory illness within 4 weeks.
- Subjects who are asthmatic or have a history of asthma.
- Allergic to chemical vapors or gases.
- Any allergic symptoms during the time of participation in the study
- Female subjects who are currently pregnant, attempting to become pregnant, or breastfeeding
- Subjects unwilling or unable to stop taking vitamin C or E or medications which may impact the results of the ozone challenge (such as, systemic steroids and beta blockers) at least 2 weeks prior to the study and for the duration of the study. Medications not specifically mentioned here may be reviewed by the investigators prior to a subject's inclusion in the study.
- Current and past smokers within 1 year.
- Uncontrolled hypertension (> 150 systolic, > 90 diastolic).
- Subjects who do not understand or speak English
- Subjects unable to perform the moderately active exercise required for the study.
- Subjects with a history of skin allergies to adhesives used in securing heart rate monitor electrodes.
- Unspecified diseases or conditions, which in the judgment of the investigator might influence the responses to the exposures, will be a basis for exclusion.
- Subjects unwilling to stop taking over-the-counter pain medications such as aspirin, Advil, Aleve or other non-steroidal anti-inflammatory medications ("NSAIDS") for 48 hr prior to the exposures and post-exposure visits.
- Subjects with a marked baseline prolongation of QT/QTc interval (e.g., repeated demonstration of a QTc interval >450 milliseconds (ms))
Plan de estudios
¿Cómo está diseñado el estudio?
Detalles de diseño
- Propósito principal: Diagnóstico
- Asignación: Aleatorizado
- Modelo Intervencionista: Asignación factorial
- Enmascaramiento: Doble
Armas e Intervenciones
Grupo de participantes/brazo |
Intervención / Tratamiento |
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Comparador de placebos: Filtered air exposure
2 hr exposure to clean, filtered air with intermittent exercise
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Exposure to 300 ppb ozone with intermittent exercise about 20 hr after exposure to each arm (ie, either air, ozone, diesel exhaust, or ozone combined with diesel exhaust)
Otros nombres:
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Experimental: Ozone
2 hr exposure to 300 ppb ozone with intermittent exercise
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Exposure to 300 ppb ozone with intermittent exercise about 20 hr after exposure to each arm (ie, either air, ozone, diesel exhaust, or ozone combined with diesel exhaust)
Otros nombres:
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Experimental: Diesel Exhaust, No ozone
2 hr exposure to whole diesel exhaust (300 ug/m3; gases + particles) with intermittent exercise; no ozone
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Exposure to 300 ppb ozone with intermittent exercise about 20 hr after exposure to each arm (ie, either air, ozone, diesel exhaust, or ozone combined with diesel exhaust)
Otros nombres:
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Experimental: Ozone + Diesel Exhaust
2 hr exposure to a combination of 300 ppb ozone an 300 ug/m3 whole diesel exhaust with intermittent exercise
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Exposure to 300 ppb ozone with intermittent exercise about 20 hr after exposure to each arm (ie, either air, ozone, diesel exhaust, or ozone combined with diesel exhaust)
Otros nombres:
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¿Qué mide el estudio?
Medidas de resultado primarias
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
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Lung Function Decrement
Periodo de tiempo: Immediately post to 24 hr post exposure
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Lung function decrements are typically expressed as changes in FEV1 and FVC.
Measurements are made pre-exposure (defined as baseline, immediately post exposure, 1-4 hr post exposure, and 24 hr post exposure (follow up).
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Immediately post to 24 hr post exposure
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Medidas de resultado secundarias
Medida de resultado |
Periodo de tiempo |
|---|---|
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Heart rate variability
Periodo de tiempo: immediately post to 24 hr post exposure
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immediately post to 24 hr post exposure
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Otras medidas de resultado
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
|---|---|---|
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plasma cytokine levels
Periodo de tiempo: immediately post to 24 hr post exposur
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Inflammation markers such as interleukin 8
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immediately post to 24 hr post exposur
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Colaboradores e Investigadores
Patrocinador
Investigadores
- Investigador principal: Michael Madden, PhD, Environmental Protection Agency (EPA)
Publicaciones y enlaces útiles
Fechas de registro del estudio
Fechas importantes del estudio
Inicio del estudio
Finalización primaria (Actual)
Finalización del estudio (Actual)
Fechas de registro del estudio
Enviado por primera vez
Primero enviado que cumplió con los criterios de control de calidad
Publicado por primera vez (Estimar)
Actualizaciones de registros de estudio
Última actualización publicada (Estimar)
Última actualización enviada que cumplió con los criterios de control de calidad
Última verificación
Más información
Términos relacionados con este estudio
Palabras clave
Términos MeSH relevantes adicionales
Otros números de identificación del estudio
- EPA 09-1344
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