Marine Biotoxins in Whole and Processed Scallops from the Argentine Sea

Abstract

Harmful algal blooms are an increasing worldwide threat to the seafood industry and human health as a consequence of the natural production of biotoxins that can accumulate in shellfish. In the Argentine Sea, this has been identified as an issue for the offshore fisheries of Patagonian scallops (Zygochlamys patagonica), leading to potentially harmful effects on consumers. Here we assess spatial and temporal patterns in marine biotoxin concentrations in Patagonian scallops harvested in Argentinian waters between 2012–2017, based on analyses for paralytic shellfish toxins, lipophilic toxins, and amnesic shellfish toxins. There was no evidence for concentrations of lipophilic or amnesic toxins above regulatory acceptance thresholds, with trace concentrations of pectenotoxin 2, azaspiracid 2 and okadaic acid group toxins confirmed. Conversely, paralytic shellfish toxins were quantified in some scallops. Gonyautoxins 1 and 2 dominated the unusual toxin profiles (91%) in terms of saxitoxin equivalents with maximum concentrations reaching 3985 µg STX eq/kg and with changes in profiles linked in part to seasonal changes. Total toxin concentrations were compared between samples of the adductor muscle and whole tissue, with results showing the absence of toxins in the adductor muscle confirming toxin accumulation in the digestive tracts of the scallops and the absence of a human health threat following the processing of scallop adductor meat. These findings highlight that paralytic shellfish toxins with an unusual toxin profile can occur in relatively high concentrations in whole Patagonian scallops in specific regions and during particular time periods, also showing that the processing of scallops on board factory ships to obtain frozen adductor muscle is an effective management process that minimizes the risk of poisonings from final products destined for human consumption.

Occurrence and Exposure Assessment of Lipophilic Shellfish Toxins in the Zhejiang Province, China

“…In the present study, the maximum concentration range of the OA group toxins was 16.5-32.5 µg OA eq./kg, which was lower than the regulatory limit of 160 µg OA eq./kg [47], and similar to the concentration reported in samples from Shenzhen (maximum concentration: 25-34.6 µg OA eq./kg) [26], the Middle Adriatic Sea (44.7 µg OA eq./kg) [63], and the Argentine Sea (12.9 µg OA eq./kg) [64]. The highest concentration of PTX2, which was recently deregulated [47][48][49], was 13 µg PTX2 eq./kg, similar to that detected in samples from Shenzhen (6 µg PTX2 eq./kg) [26] and Hebei (10-30 µg PTX2 eq./kg) [65].…”

An Occurrence and Exposure Assessment of Paralytic Shellfish Toxins from Shellfish in Zhejiang Province, China

“…To ensure that shellfish are safe for consumption, many organizations in various countries, including the U.S. Food and Drug Administration and Health Canada, have adopted a regulatory limit of 800 µg of STX equivalents/kg shellfish meat [4,[11][12][13][14]. The European Union updated STX-diHCL equivalents as the unit of measure for PSP in 2021 [15]; however, the previous unit remains more widely used in recent studies on PST levels and risk assessments worldwide [5,14,[16][17][18][19][20]. Considering the potential health risks of PSTs, the European Food Safety Authority (EFSA) recommended an acute reference dose (ARfD) of 0.5 µg STX eq./kg b.w.…”