February 6 , 2008. 3:00-4:30pm. Porter Hall 223-D, Carnegie Mellon University.

Risk communication, media amplification and the aspartame scare

Presenter: Ragnar E. Löfstedt, Professor and Director, King’s Centre for Risk Management, King’s College London

To be published in: Risk Management: International Journal 2008.

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 leukemias in female
rats. This study showing that aspartame causes cancer and was published on line 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 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 leukemias in the treated rats was considered to be unrelated to the aspartame
treatment, and most likely attributed to the high background incidence of inflammatory 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; and
· The (cancer) findings in the kidney, ureter and bladder, observed mainly in female rats, were not specific 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 time of EFSA’s press conference, and is based on interviews with relevant regulators (most notably EFSA),
scientists, stakeholders (industrialists, consumer representatives), and the media. The findings of the study note that the communication
strategies used by the Ramazzini Foundation were not transparent, were focused on sensationalising the results, were used to actively
mislead the media, and did not meet proper risk communication criteria.