Community health risk assessment after a fire with asbestos containing fallout

Background-A factory fire in Tramnere, Merseyside, England, deposited asbes tos containing fallout in an urban area. There was considerable community a nxiety for months after the incident. Therefore an assessment of the long t erm health risks of this acute environmental incident were requested by the local health authority. Methods-The facts of the incident were gathered and appraised from unpublis hed and press reports, involved personnel, and further analysis of material collected at the time of the incident. The literature on the long term hea lth risks of asbestos was reviewed, and combined with evidence on asbestos exposure to estimate community health risk. Results-Risk was almost entirely from exposure to fire fallout of chrysotil e in asbestos bitumen paper covering the factory roof. Amosite was only det ected in a few samples and in trace amounts. The number of people who lived in the area of fallout was 16000 to 48000. From a non-threshold model with assumptions likely to overestimate risk, the lung cancer risk is estimated to be undetectably small. Risk of mesothelioma from chrysotile exposure, a nd risks of lung cancer and mesothelioma from amosite exposure were based o n observational studies and were estimated to be even lower than that of lu ng cancer risk from chrysotile exposure. Academically, there are assumption s that while reasonable cannot be proven, for example, the validity of extr apolating observed risk from much higher exposures to lower exposures, esti mates of individual exposure, and that there is no threshold for asbestos t o cause cancer. Conclusions-The author is unaware of a similar study on long term health ri sks in a community exposed to asbestos in a fire. It is concluded that, usi ng methods that do not underestimate risk, risk is undetectably small. Prac tical lessons from this methodology and approach to health risk assessment are discussed.