The European Food Safety Authority (EFSA) recently published an assessment of Europeans’ acute exposure to glycerol (additive E 422) in slush-ice drinks (slushies) and dealcoholized wine, finding that both children and adults would exceed the acute reference dose (ARfD) for glycerol by consuming a single serving of either beverage type. Based on these findings, EFSA recommends that the European Commission consider establishing numerical maximum levels for glycerol in beverages.

The acute exposure assessment was conducted on a single‑consumption‑event basis considering the reported use levels and analytical data of glycerol in slushies and the proposed maximum level of 50,000 milligrams (mg) of glycerol per liter (L) in dealcoholized wine. EFSA used a conservative dose above which unintended pharmacological effects would occur for the determination of the ARfD. For a single consumption event, an ARfD of 125 mg glycerol per kilogram (kg) of body weight was derived.

For slushies, EFSA concluded that the acute exposure to glycerol per single consumption event, assuming a consumption of 250 milliliter (mL) and 500 mL for children and other population groups, respectively, would exceed the ARfD for all population groups.

For dealcoholized wine, the 95^th percentile acute exposure estimates for glycerol, at the proposed maximum level and assumed to be consumed as a substitute for flavored drinks or wine, would exceed the ARfD for all population groups.

Maximum Safe Amounts of Glycerol Beverages per Sitting

EFSA also calculated the maximum single consumption event volume of beverages containing glycerol that can be consumed by different population groups without exceeding the ARfD. For slushies, based on median reported use levels, this ranged from 82.7 mL for toddlers 1–2 years of age to 507 mL and 511 mL for adults (18–64 years) and the elderly (65 and up), respectively. The values calculated for children (3–9 years) and adolescents (10–17 years) were 160 mL and 358 mL, respectively. Notably, the reported use levels are lower than the levels reported in analytical data.

For dealcoholized wine based on the proposed maximum level, the maximum single consumption event volume range across population groups was 30.9–191 mL.

Theoretical Maximum Levels for Glycerol as an Additive in Beverages

Theoretical maximum levels for glycerol, when used as an additive in beverages, at which exposure would not exceed the ARfD were also calculated for all population groups. For toddlers, this theoretical maximum level would be 250 mL of beverage with 6,200 mg/L glycerol concentration; for children, 250 mL at 12,000 mg/L; for adolescents, 500 mL at 13,400 mg/L; for adults, 500 mL at 19,000 mg/L; and for the elderly, 500 mL at 19,100 mg/L.

Based on the proposed maximum level in dealcoholized wine, EFSA concluded that toddlers, children, and adolescents should consume less than 31 mL, 60 mL, and 134 mL, respectively, in a single consumption event to avoid exceeding the ARfD. For adults and the elderly, consumption should be limited to less than one glass (190 mL).

Overall, EFSA determined that, to ensure that toddlers and children do not exceed the glycerol ARfD after consuming a volume of 250 mL of beverages in a single sitting, and that adults do not exceed the ARfD after consuming 500 mL, glycerol concentrations should be below the lowest reported use level in slush ice drinks (17,400 mg/L).

Slushies Sickened Children, Prompting Glycerol Reassessment

In 2023, the UK Food Standards Agency (FSA) advised manufacturers and retailers not to sell slushies containing glycerol to children under four years of age, and that children under ten years of age should not be offered free refills. In 2024, the Food Standards Agency of Ireland (FSAI) followed suit. This advice was prompted by cases in Scotland where children were hospitalized because of glycerol intoxication. Additionally, EFSA’s assessment of acute glycerol exposure cited 21 cases where children aged 2–6 years became unwell shortly after consuming slushies.

Glycerol intoxication can occur when excessive levels of glycerol are consumed in a short period of time. Symptoms typically present within an hour of consumption and can include shock, hypoglycemia, and loss of consciousness.