Past, Current and Future Techniques for Monitoring Paralytic Shellfish Toxins in Bivalve Molluscs

Area of Science:

• Marine biology
• Food safety
• Toxicology

Background:

• Paralytic shellfish poisoning (PSP) poses a significant human health risk.
• Shellfish contamination with saxitoxin-class toxins necessitates regulatory monitoring.
• Ethical considerations (3Rs framework) guide toxicity testing development.

Purpose of the Study:

• To review current methods for assessing paralytic shellfish toxins (PSTs) in shellfish.
• To evaluate the suitability of in vitro and in vivo methods for regulatory and non-regulatory purposes.
• To determine the most accurate approach for assessing food safety risks associated with PSTs.

Main Methods:

• Literature review of in vivo animal bioassays, in vitro assays, and analytical methods.
• Analysis of the correlation between in vitro assay results and actual toxicity.
• Evaluation of toxicity equivalence factors (TEFs) derived from animal toxicity data.

Main Results:

• In vitro methods are effective for screening shellfish for non-regulatory purposes.
• In vitro assays (receptor/antibody binding) do not accurately correlate with toxin potency.
• Animal bioassays are currently indispensable for accurate toxicity quantification and TEF calculation.
• Analytical methods using TEFs derived from oral animal toxicity data provide accurate food safety risk assessment.

Conclusions:

• Accurate toxicity data, particularly from animal bioassays, is crucial for setting regulatory limits and ensuring food safety.
• While in vitro methods offer screening potential, they cannot replace animal testing for precise toxicity quantification.
• The ultimate goal of replacing animal testing must not compromise human health protection from PSP.