Acute toxicity assessment of diarrhetic shellfish toxins by voluntary feeding in mice

Diarrhetic shellfish toxins (DSTs) and phytoplankton species producing them have been frequently reported in seawater worldwide. They accumulate in shellfish and pose a significant threat to the environment and the health of seafood consumers. The goal of this study was to evaluate the acute toxicity of DSTs administered to mice via voluntary ingestion through bread. This is a method for the delivery of DSTs that provided convenient dosing, reduced animal stress and mimicked human exposure more accurately than oral gavage administration. Over 24 h, key parameters including clinical signs were meticulously recorded. The results showed a dose-dependent reduction in food and water consumption and significant relative body weight loss, with OA and DTX1 inducing more pronounced gastrointestinal disturbances at lower doses than DTX2. This is the first study to compare toxicity of DSTs administered by voluntary feeding where diarrhea is the main symptom. Effective dose 50 for watery diarrhea in the first 3 h highlighted that DTX2 is significantly less toxic than OA and DTX1. These insights enhance our comprehension of DTXs toxicity and contribute to the risk assessment of the dietary exposure of DSTs form shellfish.