Sweet but toxic? An ecotoxicity assessment of the artificial sweetener sucralose using transcriptomics

This study investigated how the artificial sweetener sucralose affects gene expression in Daphnia magna, Danio rerio and Lemna minor in order to derive mechanistic information relevant for environmental risk assessment. The main tests were conducted according to OECD test guidelines 202, 221 and 236 and were combined with transcriptomics. Test concentrations were 10 µg/L and 100 mg/L. For D. magna and D. rerio, pooled animals from each exposure group and corresponding controls were sampled at test end for whole-animal RNA extraction. For L. minor, whole plant tissue from each exposure group and corresponding controls was sampled at test end for RNA extraction. Poly(A)-enriched RNA was sequenced (paired-end, 150 bp) on an Illumina NovaSeq platform, followed by alignment to the respective reference genome and differential expression analysis using a DESeq2-based workflow with independent hypothesis weighting, data-driven log2 fold-change thresholds, and multiple-testing correction to define robust sets of differentially expressed genes per substance and concentration. Overrepresentation analysis of Gene Ontology terms using a common detected-gene background then mapped these gene-level changes to biological processes.