Dietary intake of sulfites ‘could be a safety concern’: EFSA

Sulfite occurs naturally in our bodies as well as in foods such as apples, rice, onions and cabbage, and beverages such as wine. Sulfites may be used to halt on-going fermentation during the winemaking process and are added as preservatives and antioxidants (for example, to prevent browning) to a range of foodstuffs including dried fruit and vegetables, potato-based products, beer and malt beverages, wine, and fruit juices.

In a recent updated assessment of sulfur dioxide (E220) and sulfites (E221-228), EFSA’s experts concluded that the intake of sulfates ‘could’ represent a safety concern for people who consume ‘high’ levels in their diets. However, the opinion continued, gaps in toxicity data meant the extent of certain adverse health effects could not be confirmed.

“The available toxicity data was insufficient for us to derive an Acceptable Daily Intake (ADI) level. Instead, we calculated margins of exposure (MOE) considering dietary intakes and the dose associated with neurotoxic effects in animal tests,”​ Dr Maged Younes, Chair of EFSA’s Panel on Food Additives and Flavourings, said. “An ADI is a threshold below which we know the daily intake is safe. When there is evidence of harmful effects but not enough for us to confirm how much is safe, the MOE tells us if current intakes are likely to be harmful.”​

The MOE is a ratio between the lowest estimated dose at which an adverse effect is observed and the level of exposure to the substance. In the case of sulfites, a ratio below 80 could indicate a safety concern, according to the food safety agency.

Estimated intakes ‘potentially exceed what is safe’

Based on the MOE calculation, EFSA’s experts concluded there is a risk that intake levels ‘potentially’ exceed levels that would be considered safe.

“The MOEs we calculated were below 80 for high consumers in all population groups except for adolescents. This means that estimated intakes for these consumers potentially exceed what would be considered safe, by up to 12.5% for children (3-10 year olds) and up to 60% for adults,​” Dr Matthew Wright, Chair of EFSA’s working group on sulphur dioxide-sulphites, said.

The Panel found evidence of adverse health effects on the central nervous system such as a delayed response of nerve cells to stimuli, an early sign of nervous system dysfunction. EFSA’s scientists also restated their previous recommendation to further investigate hypersensitivity or intolerance among some sensitive consumers due to knowledge gaps.