Barker, Richard David; (1996) The aetiology and outcome of asthma caused by acid anhydrides. Doctoral thesis (M.D), UCL (University College London).

Text The_aetiology_and_outcome_of_a.pdf Download (10MB)

Abstract

Acid anhydrides (AA) are reactive low molecular weight chemicals used in the manufacture of plasticisers, resins and surface coatings. They may cause asthma, associated with specific IgE, directed at conjugates of AA with human serum albumin (HSA). Little is known of the factors that determine why one exposed worker develops occupational asthma when his workmate is spared. A cohort of phthalic, maleic and trimellitic anhydride exposed workers, employed between 1960 and 1992, was studied. Symptoms and employment histories were recorded, exposure measurements were made and a retrospective exposure assessment was done. Each participant underwent skin prick tests with common inhalant allergens and AA-HSA conjugates. Participants gave blood for measurement of specific IgE and HLA typing. In addition they underwent a measurement of bronchial responsiveness. In a further study, six women with asthma caused by AA were examined for persistence of asthma twelve years after they had left the factory in which they developed their disease. Five hundred and six people fulfilled the cohort definition and information was obtained from 401 (79.2%). Twelve (3.2%) subjects had immediate skin test reactions to AA-HSA and 34 (8.8%) reported new work related chest symptoms. Immediate skin test reactions to AA-HSA were associated with work related respiratory symptoms and were more common among those who smoked at the time of exposure to AA. There was a higher risk of immediate skin test reactions to AA-HSA and work related chest symptoms amongst those with higher exposures to AA. Bronchial hyperresponsiveness (BHR) was associated with atopy, immediate skin test reactions to AA-HSA and cumulative cigarette consumption but was not associated with cumulative exposure to AA. Workers sensitised to trimellitic anhydride were more likely to have the HLA-DR3 genotype. The six women with asthma caused by AA had persistent symptoms and BHR twelve years after they had last worked with the chemical that had caused their disease. Extent of exposure, cigarette smoking and HLA type are risk factors for occupational asthma caused by acid anhydrides. This has implications for industry and may be relevant to asthma caused by common inhalant allergens.

Download activity - last month

Export as JSONXMLCSV

Download activity - last 12 months

Export as JSONCSVXML

Downloads by country - last 12 months

Export as XMLCSVJSON

Archive Staff Only

View Item