Should we be frightened of bracken? A review of the evidence.

摘要: OBJECTIVE: To assess the risk to human health of plant bracken (Pteridium sp). DESIGN: An evaluation studies and animal populations exposed bracken, together with a review expert reports advice public. MAIN RESULTS: Bracken induced disease has been demonstrated in animals both laboratory field studies. Depending on species, diseases associated have included; cancers alimentary urogenital tract, lung breast; haematuria; retinal degeneration; and, thiamine deficiency. Potential exposure is through: food either directly (people some parts world eat as traditional dish) or indirectly by consuming fed bracken; milk; water; inhalation ingestion spores; insect vectors. Four (two analytical two observational) failed adequately confounding factors other sources bias, so that conclusions about from cannot firmly be drawn. Establishing also extremely difficult (such United Kingdom) where direct consumption rare. CONCLUSION: common worldwide. It toxic many species several organ systems. There no tumour (or disease) pathognomic animals, though tract seem most commonly associated. not possible extrapolate models humans. Studies populations, do establish clear health, largely because methodological problems. Testing evidence against criteria causality only fulfils criterion biological plausibility. Despite this, current public information implies serious increasing media coverage subject likely lead greater concern. Further epidemiological are required.