Defining a hidden food safety risk in children

Research published in Archives of Disease in Childhood identified a serious and previously underrecognised risk associated with slush ice drinks marketed to children, directly influencing food safety guidance and regulatory discussions across the UK, Ireland, Germany, and the European Union.

The study, ‘Glycerol intoxication syndrome in young children, following the consumption of slush ice drinks’, ¹ demonstrated that glycerol, increasingly used in sugar-free slush ice drinks following the introduction of sugar-sweetened beverage levies in Ireland and the UK, can cause acute severe illness in young children.

Manufacturers had replaced sugar with glycerol (E422), which has useful properties to maintain the slush effect while reducing sugar content. The research defined ‘glycerol intoxication syndrome’ in children for the first time and provided evidence that rapidly informed food safety guidance in the UK and Ireland, while also contributing to wider European regulatory discussions. In 2026, the European Food Safety Authority recommended that the European Commission consider establishing numerical maximum levels for glycerol in beverages.

The research

The multicentre study investigated 21 children aged between 2 and 7 years who became seriously unwell shortly after drinking slush ice drinks. Most became drowsy or lost consciousness, and developed dangerously low blood sugar and a build-up of acid in the blood. The symptoms were so severe that they initially resembled rare inherited metabolic conditions. All children were admitted to hospital for treatment, but none were found to have an underlying metabolic disorder, and all recovered fully.

Researchers found clear evidence that the children had consumed high amounts of glycerol, a widely used sweetener increasingly used in large amounts in sugar-free slush drinks due to its antifreeze properties.

The study was the first to describe “glycerol intoxication syndrome” in children and the first published research linking the condition to slush ice drinks.

The impact

The research rapidly influenced food safety policy and clinical guidance. In recognition of its wider public health and policy impact, the study researchers subsequently received the University College Dublin Research Impact Award and Policy Impact Award in January 2026. ²

• In the UK, the Food Standards Agency undertook a rapid risk assessment and revised national guidance in 2025, recommending that children under 7 should not consume slush ice drinks containing glycerol and that older children should limit their intake. ³ Food Standards Scotland subsequently issued updated guidance for retailers and industry to support implementation of the new recommendations. ⁴
• The Food Safety Authority of Ireland had been alerted during the research by the authors and raised concerns about glycerol exposure in children, and contributed to wider European discussions on slush ice drinks containing glycerol.
• Germany’s Federal Institute for Risk Assessment (BfR) subsequently undertook a health risk assessment and concluded that glycerol-containing slush ice drinks may pose health risks to children. ⁵
• The study additionally improved clinical awareness. According to the author, glycerol intoxication was included in TOXBASE, while the Royal College of Emergency Medicine issued safety guidance for emergency departments. 
• The European Food Safety Authority (EFSA) published a new scientific opinion referencing the study, which included the recommendation for the European Commission to consider establishing numerical maximum levels for glycerol (E 422) when used in beverages. ⁶
• The paper attracted substantial international attention, with more than 29,000 full-text downloads within six months and an Altmetric score of 1,142, placing it in the top 5% of all research outputs tracked by Altmetric.

“We recognised a pattern of severe illness in children that had not previously been clearly linked to slush ice drinks. Publishing the research helped consolidate the evidence and ensured the findings reached the people who could act on them – from clinicians and toxicologists to food safety authorities and policymakers.”

Ellen Crushell
Clinical Professor, School of Medicine, University College Dublin; Consultant Paediatrician in inherited metabolic disorders; Deputy Chief Medical Officer, Department of Health, Ireland