Sucralose

A MultiFlow assay, a high-throughput genotoxicity screening tool, and a micronucleus (MN) test that detects cytogenetic damage both indicated that sucralose-6-acetate is genotoxic. The mechanism of action was classified as clastogenic (produces DNA strand breaks).

A 2023 peer-reviewed in vitro study found sucralose-6-acetate (an impurity in, and digestive metabolite of, sucralose) to be genotoxic and clastogenic, with exposure from a single sweetened drink potentially exceeding the genotoxicity threshold of toxicological concern.

When sucralose is heated to temperatures above 120 degrees Celsius for a prolonged period, this leads to gradual decomposition and dechlorination of the substance, producing potentially harmful chlorinated organic compounds. The BfR advises consumers not to heat food containing sucralose above 120 degrees C.

Germany's federal risk assessment institute (BfR) advises that heating sucralose above 120 degrees C can produce harmful chlorinated organic compounds, and recommends not heating sucralose-containing food above that temperature.

The Panel could not conclude on the safety of the proposed extension of use of E 955 in fine bakery wares due to uncertainties regarding the potential formation of chlorinated compounds under the wide range of baking processes; intake at current uses is of low concern except when heated.

In its February 2026 re-evaluation, EFSA reaffirmed sucralose is safe at current authorized uses (ADI 15 mg/kg bw/day) but could not conclude it is safe for an extended use in fine bakery wares, citing uncertainty over chlorinated compounds forming when sucralose is heated.