New Methods To Detect Marine Biotoxin In Shellfish

Community-level talks have been under way for several months in view to replacing the mouse bioassy, which is the current benchmark method for monitoring shellfish safety, by chemical tests for direct detection of 13 regulated lipophilic marine biotoxins in shellfish.

AFSSA said its dual approach would “make it possible to anticipate the consequences of atypical toxicities that would not be fully assessed using regulatory monitoring”.

Chemical test methods have the advantage of enabling a much more detailed analysis of regulated lipophilic toxins than the mouse bioassay while also providing reliable quantitative results. However, such methods favour detection within a predetermined list of chemical substances, making it impossible to detect possible emerging toxins or new analogs of known toxins.

The agency recommends basing the new monitoring system on continued used of the mouse bioassay but with modified frequency of its use. This would provide data for a safeguard unit that could supply additional investigations, warning measures and/or management measures in certain cases, especially in the event of a positive mouse test result unexplained by chemical analysis.

The agency points out that the system should be rapidly modified to take into account the risks related to phycotoxins produced by various species of the genus Ostreopsis found on the Mediterranean coast.

This combination of monitoring and safeguarding will mean that both the chemical tests and the mouse bioassay will be used to their fullest advantage, since the latter provides highly specific and detailed analysis of known toxins while the former, less precise, provides a more global view of possible sources of toxicity. Together they can ensure that stringent requirements for consumer protection are maintained.