A widely-used artificial sweetener, Aspartame, may soon be listed as a potential carcinogen by the International Agency for Research on Cancer (IARC), a prominent global health institution, according to insider sources. This possible categorisation, expected in July, is already sparking apprehension within the food and beverage industry, and among regulatory authorities.

Aspartame, a component in numerous products, such as Coca-Cola’s diet beverages, Mars’ Extra gum, and certain Snapple drinks, would be flagged as “possibly carcinogenic to humans” by the IARC, which operates under the umbrella of the World Health Organization (WHO). This follows a determination by external experts earlier this month.

The role of IARC is to assess potential hazards, considering all published evidence. However, the organisation does not offer recommendations on safe levels of consumption, which is the task of WHO’s expert committee on food additives, known as JECFA, and national regulatory bodies.

Past IARC classifications have influenced consumer behaviour, triggered legal action, and compelled manufacturers to alter their recipes, leading to critique that IARC’s decisions could potentially mislead the public.

Simultaneously, JECFA is reassessing the use of Aspartame. Since 1981, JECFA has upheld that Aspartame is safe for consumption within specified daily limits, a view largely accepted by regulatory bodies worldwide.

While both IARC and JECFA’s evaluations remain confidential until July, an IARC representative noted that the two committees’ findings are complementary, with IARC’s assessment being “the first fundamental step to understand carcinogenicity”.

The industry and regulatory bodies, however, express concern about potential confusion due to the simultaneous evaluations. Japan’s Ministry of Health, Labour and Welfare has urged both bodies to synchronise their Aspartame reviews to minimise public confusion.

The IARC’s rulings have had profound implications in the past. For instance, in 2015, the IARC concluded that glyphosate is “probably carcinogenic”, a decision that impacted companies even years later despite other organisations contesting the finding.

Moreover, the IARC has been criticised for instigating unnecessary alarm over substances or situations that are hard to avoid. They have previously classified working overnight, consuming red meat, and using mobile phones as “probably” or “possibly cancer-causing”, which will be the same label given to Aspartame.

There are concerns about the scientific comprehensiveness of the IARC’s review of Aspartame, with some critics claiming that it leans heavily on discredited research. This impending decision may result in misleading consumers, warn some industry representatives.

Aspartame, a subject of extensive research, was linked to a slightly higher cancer risk in a large observational study in France last year. This finding echoed a study from the early 2000s, which reported some cancers in mice and rats were linked to Aspartame. However, the methodology of these studies has been questioned, and neither definitively proved that Aspartame caused the increased cancer risk.

Aspartame is globally approved for use by regulatory authorities, based on a thorough review of the available evidence. Major food and beverage manufacturers have consistently defended their usage of the ingredient. The IARC stated it evaluated 1,300 studies for its June review.

The potential classification of Aspartame as a possible carcinogen is intended to spur further research, which will aid agencies, consumers, and manufacturers in drawing more definitive conclusions. However, it is likely to spark a renewed debate about the IARC’s role, as well as the safety of sweeteners in general.