On 14 July 2005, the Ramazzini Foundation held a press conference on the cancer risks posed by the sweetener aspartame, which received worldwide media attention. Scientists at the Ramazzini Foundation found that when administered to rats for their entire life span, aspartame, an artificial sweetener used in more than 6,000 food and pharmaceutical products, induces an increase in lymphomas and leukaemias in female rats. This study showed that aspartame causes cancer and was published online in the Foundation ' s in-house journal European Journal of Oncology . After a second publication on aspartame by the same institute, a number of scientists and European regulators started to question the validity of Ramazzini ' s findings. Events culminated following the publication of the European Food Safety Authority (EFSA) expert opinion on 5 May 2006 and the resulting press conference in Rome where the Authority announced that the Ramazzini study was problematic. It pointed out:The slight increase in cancers known as lymphomas and leukaemias in the treated rats was considered to be unrelated to the aspartame treatment, and most likely attributed to the high background incidence of infl ammatory changes in the lung. There was no dose -response relationship with respect to increasing doses of aspartame. With regard to the malignant tumours of the peripheral nerves, the numbers of tumours were low with no clear dose -response relationship over a wide dose range. The (cancer) fi ndings in the kidney, ureter and bladder, observed mainly in female rats, were not specifi c to aspartame. This paper evaluates the communication and active social amplification of Ramazzini ' s research on aspartame, from the time of Ramazzini ' s initial press conference to the • • • •