Preventing occupational asthma what makes an occupational disease ripe for prevention? what is the role of the academic/clinical community? what influences business? Paul Cullinan - Pepys 2, Toronto

technological influences aetiologic understanding amenable risk factors technology for reduction of risk factors effective 2 o prevention societal influences frequencynature + perception individual costs societal costs corporate influences frequencycostsimpact on workforce impact on consumers impact on reputation competitiveness influence of workforce influence of consumer organisations Factors influencing the prevention of occupational asthma favourable +/- unfavourable

Approaches to the prevention of occupational asthma elimination substitution ‘molecular design’ pre-employment eugenics exposure control surveillance (delivery)

first author agentmethodsdesign surveillanceeducationexposure reduction DrexlerAAO X O LissAA??O X O HuntlatexO X O Saarylatex??O X O AllmerslatexO O O X O O O Tarlo/LisslatexO X O FisherLAAO X O BothamLAAO O X O O TarloNCOO O O X O O O Juniper/ Cathcart detergent enzymes O O X O O Studies of primary prevention YN?

Studies of primary prevention: the effects of enhanced surveillance Tarlo and Liss

Incidence in studies of prevention first author agentincidence DrexlerAA LissAA Huntlatexy (crude) Saarylatex Allmerslatex Tarlo/Lisslatex FisherLAAy (not stated) BothamLAAy (?) TarloNCO Juniper/ Cathcart detergent enzymes YN

Incidence and occupational asthma risk m time from first exposure (employment) risk unusually sensitive exposure individual immunity ---- herd immunity who is ‘at risk’? group risk dependent on exposure and turnover in a state of steady exposure risk depends on turnover

Interpreting prevention studies

Exposure limits in occupational asthma something to aim at (NCO, subtilisins, bakery dust, amylase…….. but: very large # of agents capturing relevant exposures is technically difficult thresholds? measuring biological allergens is technically difficult SME’s don’t understand them ‘of limited value in exposure control’ have they ever ‘worked’? in-house limits first authorAgentExposure limits DrexlerAA LissAA Huntlatex Saarylatex Allmerslatex Tarlo/Lisslatex FisherLAA BothamLAA TarloNCOexternal Juniper/ Cathcart detergent enzymes internal

supermarket bakeries Secondary prevention: how good is routine surveillance?

Incentives towards prevention Sticks: the costs of a case… regulation reputation Carrots: insurance premiums tax breaks what motivates industry? SME vs the large corporation (where is OA located?) occupational lung diseases in history

Barriers to prevention: a chief medical officer’s view Paul, Thank you so much for the meeting yesterday. It was very interesting although I’m not sure it will change our practice. X’s parting shot to me was that he didn’t see why we should investigate anyone for OA as the insurance companies would do it anyway and we might as well just dismiss employees with bakers’ asthma as it would probably be cheaper in the long run. We must admire the human race – etiquette demands it of us (Mark Twain)