Diesel exhaust causing low-dose irritant asthma with latency?
BACKGROUND
Diesel exhaust exposure may cause acute irritant-induced asthma and potentiate allergen-induced asthma. There are no previous reports of occupational asthma due to diesel exhaust.


OBJECTIVE
To describe occupational asthma with latency in workers exposed to diesel exhaust in bus garages.


METHODS
The Shield database of occupational asthma notifications in the West Midlands, UK, was searched between 1990 and 2006 for workers where diesel exhaust exposure was thought to be the cause of the occupational asthma. Those without other confounding exposures whose occupational asthma was validated by serial peak expiratory flow (PEF) analysis using Oasys software were included.


RESULTS
Fifteen workers were identified with occupational asthma attributed to diesel exhaust. Three had validated new-onset asthma with latency. All worked in bus garages where diesel exhaust exposure was the only likely cause of their occupational asthma. Occupational asthma was confirmed by measures of non-specific reactivity and serial measurements of PEF with Oasys scores of 2.9, 3.73 and 4 (positive score > 2.5).


CONCLUSIONS
The known non-specific irritant effects of diesel exhaust suggest that this is an example of low-dose irritant-induced asthma and that exposures to diesel exhaust in at least some bus garages are at a sufficient level to cause this.
Adewole
Femi
F
Department of Medicine, Obafemi Awolowo University/Teaching Hospitals Complex, Ile-Ife, Nigeria. adewolef@yahoo.co.uk
Moore
Vicky C
VC
Robertson
Alastair S
AS
Burge
P S
PS
D017668:Age of Onset; D000395:Air Pollutants, Occupational / Q000633:toxicity*; D001249:Asthma / Q000139:chemically induced* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles; D009784:Occupational Diseases / Q000139:chemically induced* / Q000503:physiopathology; D016273:Occupational Exposure / Q000009:adverse effects*; D010366:Peak Expiratory Flow Rate / Q000502:physiology; D013997:Time Factors; D001335:Vehicle Emissions / Q000633:toxicity*
D000395:Air Pollutants, Occupational; D001335:Vehicle Emissions