APPROXIMATELY 4,000 tons of edible beans, mainly Phaseolus vulgaris varieties, are imported into Australia annually. Under the quarantine regulations1, the majority of these beans are treated on entry to destroy their viability, thereby preventing the introduction and transmission of various plant diseases. Methyl bromide is commonly used for this purpose. It was decided to investigate the possibility of using γ-radiation as an alternative method of treatment, as it is well known that low doses of γ-radiation inhibit seedling growth2–4. The radiation dose required to destroy viability in several different varieties of imported beans was therefore determined, as well as the effects of radiation on various chemical constituents of one type of bean, the baby lima.