Ignite Creation Date:
2024-05-05 @ 11:23 AM
Last Modification Date:
2024-10-26 @ 9:06 AM
Study NCT ID:
NCT00013728
Status:
COMPLETED
Last Update Posted:
2006-03-23
First Post:
2001-03-28
Brief Title:
Asthma Exposure to Peaks in Particulate Air Pollution
Sponsor:
National Institute of Environmental Health Sciences NIEHS
Organization:
National Institute of Environmental Health Sciences NIEHS
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2006-03
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
We are testing the following two hypotheses 1 Peaks in hourly exposures to airborne particulate matter PM of outdoor origin will be more closely associated with acute asthmatic responses to particles than 24-hour average exposures in susceptible individuals 2 Personal exposure to PM and estimated particle dose to the lungs will be more closely associated with daily asthma severity than standard outdoor particle concentrations measured as 24-hour averages at governmental monitoring sites
Detailed Description:
We are testing the following two hypotheses 1 Peaks in hourly exposures to airborne particulate matter PM of outdoor origin will be more closely associated with acute asthmatic responses to particles than 24-hour average exposures in susceptible individuals 2 Personal exposure to PM and estimated particle dose to the lungs will be more closely associated with daily asthma severity than standard outdoor particle concentrations measured as 24-hour averages at governmental monitoring sites Toxicological data for asthma exacerbations from particulate matter PM suggests that particle deposition in the lower respiratory tract can cause inflammatory and lung function changes suggestive of asthma pathology There is now a scientific need to explain epidemiological findings of ambient PM effects on asthmatics at mass concentrations below what is expected from toxicological data to be harmful One possibility is that study participants are encountering unmeasured short-term excursions of particle mass levels capable of inducing adverse reactions in the lung but this effect is only captured somewhat by the regulatory standard of 24-hour averages Our research in southern California is vital to the current controversy regarding regulatory standards given that a health-based scientific rationale for any specific PM averaging time is not established
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None