AZA Toxin Profiles by LC-HRMS in Shellfish from Šibenik Bay: AZA-2 Predominant Analog

Area of Science:

• Marine toxicology
• Analytical chemistry
• Food safety

Background:

• Azaspiracids (AZAs) are marine polyether biotoxins from dinoflagellates.
• These toxins accumulate in filter-feeding organisms, posing risks to human health and seafood safety.

Purpose of the Study:

• To conduct the first comprehensive analysis of azaspiracid analogs in Adriatic Sea shellfish.
• To identify and quantify specific AZA congeners and detect novel analogs.

Main Methods:

• High-resolution mass spectrometry (HRMS) was employed for detailed analysis.
• Shellfish samples were collected from Šibenik Bay over a five-month period (January-May 2024).
• Spectral data analysis included fragmentation patterns and consideration of ¹³C isotope effects.

Main Results:

• AZA-2 was quantified, with peak concentrations in early January.
• Several known AZA analogs (AZA-6, AZA-9, AZA-10, AZA-19, AZA-41, AZA-43) were identified.
• A potentially new analog (m/z 884.4928) structurally similar to AZA-19 was detected.

Conclusions:

• The Adriatic Sea shellfish harbor multiple azaspiracid analogs, some with high toxic potential.
• Current regulatory monitoring programs may underestimate the risk due to limited analog inclusion.
• Expanded monitoring to include more than three AZA analogs is recommended for enhanced seafood safety.