According to the European Food Safety Authority (EFSA), on the basis of all the currently available evidence, a further review of the safety of aspartame is not necessary.
EFSA also says there is no need to revise the established acceptable daily intake of the sweetner.
The European Commission had requested that EFSA review research from the Ramazzini Institute in Bologna, which claimed to have shown that rats given dosages of aspartame equivalent to the Acceptable Daily Intake (ADI) may develop tumours.
Aspartame, an intense sweetener, has been approved for use in foods and as a table-top sweetener for more than 20 years in many countries throughout the world.
Extensive investigations have been carried out on aspartame and its breakdown products through experimental animal and human studies, intake studies and post-marketing surveillance.
In addition to a number of safety evaluations conducted in the past, the Scientific Committee on Food (SCF) carried out a review of all original and more recent studies on aspartame in 2002 and reconfirmed that aspartame is safe for human consumption.
However, since it was introduced onto the market, the safety of aspartame has been a controversial issue.
In 2005, scientists from the European Ramazzini Foundation suggested that aspartame can cause cancer and that the current guidelines on the use and consumption of the sweetener should be re-evaluated.
EFSA's Scientific Panel of Food Additives, Flavourings, Processing Aids and Materials in Contact with Food (AFC), immediately undertook the evaluation of the new findings and requested that all study details necessary for the assessment be provided.
EFSA has concluded that 'on the basis of all the evidence currently available, that there is no need to further review the safety of aspartame nor to revise the previously established ADI'.
The panel identified a number of issues that made interpretation of the findings difficult and indicated that the results of the study may not be reliable.
The study used more animals per dose group and a larger number of doses than conventional carcinogenicity studies and therefore had the potential to be more sensitive to low incidence effects.
A high background incidence of chronic inflammatory disease in the lung and other organs was observed in all the animal groups including controls which did not receive aspartame, and this was considered to be a major confounding factor.
In detail the Panel concluded the following:
- The slight increase in incidence of lymphomas and leukemias in treated rats was considered to be unrelated to aspartame treatment and most likely attributed to the high background incidence of inflammatory changes in the lung and there was no dose-response relationship with respect to increasing doses of aspartame.
- The findings in the kidney, ureter and bladder, observed mainly in female rats, were not specific to aspartame and have been observed with a number of chemicals administered to rats at high dose levels and are normally the result of irritation or imbalances in calcium metabolism specific to rats and are of no relevance for humans.
- With regard to malignant tumors of the peripheral nerves, the numbers of tumours were low with no clear dose- response relationship over a wide dose range.
- There is also uncertainty about the diagnosis of these tumours.
Dr. Herman Koëter, Acting Executive Director of EFSA says, the results of the new study on aspartame do not provide a scientific basis for reconsidering its use in foods and should any new information become available in the future, EFSA will review these as a matter of priority.