Controlled Exposure to Diesel Exhaust in Subjects With Allergic Rhinitis

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01617330

Acronym

DALLER

Enrollment

Registered

2012-06-12

Start date

2001-03-31

Completion date

2002-02-28

Last updated

2012-06-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Allergic Rhinitis

Keywords

Particulate matter, Air pollution, Diesel exhaust, Allergic rhinitis

Brief summary

Proximity to traffic, particularly to diesel-powered heavy-duty vehicles, has been associated with inducing and enhancing allergies in children and adults. To investigate the basis for this association, a controlled exposure of allergic rhinitics to diesel exhaust was performed at a dose known to be pro-inflammatory in healthy individuals. The hypothesis was that airway inflammation would be augmented in allergic rhinitics following exposure to diesel exhaust at an environmentally pertinent particulate matter concentration. Fourteen allergic rhinitics were exposed in a double-blinded, randomised trial to both diesel exhaust at 100 microgram/m3 PM10 (representing an aerosol of nanoparticulate combustion particles, mean diameter 80 nm) and filtered air for two hours on separate occasions. Bronchoscopy with endobronchial mucosal biopsies and airway lavage was performed 18 hours post-exposure, and samples were analysed for markers of inflammation.

Interventions

PROCEDUREBronchoscopy

Bronchoscopy with endobronchial biopsy sampling and bronchoalveolar lavage (BAL) 18 hours post exposure. Airway inflammation was assessed.

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

20 Years to 45 Years

Healthy volunteers

Inclusion criteria

* History of seasonal allergic rhinitis requiring medical treatment only during the pollen season and were classified as mild and intermittent according to ARIA guidelines. * Positive skin prick test to airborne allergens * Normal lung function * Negative Metacholine challenge

Exclusion criteria

* Current smoking or a previous history of smoking. * Asthma * Chest infection within six weeks prior to or during the study * Current use of non-steroidal anti-inflammatory drugs * Current vitamin C or E supplementation * Current use of topical nasal steroids.

Design outcomes

Primary

Measure	Time frame	Description
Airway inflammation	18 hours post exposure	Bronchoscopy with endobronchial mucosal biopsies and airway lavage was performed 18 hours post-exposure to diesel exhaust and filtered air, and samples were analysed for markers of inflammation.

Countries

Sweden

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026