Warm temperature acclimation impacts metabolism of paralytic shellfish toxins from Alexandrium minutum in commercial oysters

Abstract

Species of Alexandrium produce potent neurotoxins termed paralytic shellfish toxins and are expanding their ranges worldwide, concurrent with increases in sea surface temperature. The metabolism of molluscs is temperature dependent, and increases in ocean temperature may influence both the abundance and distribution of Alexandrium and the dynamics of toxin uptake and depuration in shellfish. Here, we conducted a large-scale study of the effect of temperature on the uptake and depuration of paralytic shellfish toxins in three commercial oysters (Saccostrea glomerata and diploid and triploid Crassostrea gigas, n = 252 per species/ploidy level). Oysters were acclimated to two constant temperatures, reflecting current and predicted climate scenarios (22 and 27 °C), and fed a diet including the paralytic shellfish toxin-producing species Alexandrium minutum. While the oysters fed on A. minutum in similar quantities, concentrations of the toxin analogue GTX1,4 were significantly lower in warm-acclimated S. glomerata and diploid C. gigas after 12 days. Following exposure to A. minutum, toxicity of triploid C. gigas was not affected by temperature. Generally, detoxification rates were reduced in warm-acclimated oysters. The routine metabolism of the oysters was not affected by the toxins, but a significant effect was found at a cellular level in diploid C. gigas. The increasing incidences of Alexandrium blooms worldwide are a challenge for shellfish food safety regulation. Our findings indicate that rising ocean temperatures may reduce paralytic shellfish toxin accumulation in two of the three oyster types; however, they may persist for longer periods in oyster tissue.

Combined effects of warming and acidification on accumulation and elimination dynamics of paralytic shellfish toxins in mussels Mytilus galloprovincialis

“…The same trend was previously described by Farrell et al (2015) In contrast, a reduction of nearly 50 % of clearance rates were reported in mussels M.…”

“…Most studies on climate change effects in shellfish have focused on a single driver (e.g. temperature, acidification, salinity) (Anestis et al, 2010(Anestis et al, , 2007Farrell et al, 2015;Fernández-Reiriz et al, 2012). A reduced number of studies addressed the combination of two variables.…”

“…Regarding marine biotoxins, namely paralytic shellfish poisoning toxins, temperature increase seems to affect their accumulation and elimination reducing both in oysters (Farrell et al, 2015) and increasing elimination surf clams (Bricelj et al, 2014).…”

Dinoflagellates: Ecological Approaches and Spatial Distributions in Malaysia Waters

“…[40] Diarrheic Shellfish Poisoning (DSP) Okadoic acids Dinophysis, Procentrum [41] Neurotoxic Shellfish Poisoning (NSP) Brevetoxin Karenia brevis [42] Ciguatera Shellfish Poisoning (CFP) Ciguatoxin Gambierdiscus toxicus [43] the onset of paralysis. Blocking of sodium conductance eventually generates symptoms of numbness, tingling sensation of the oral parts and nausea to the patient.…”

Testing a text mining tool for emerging risk identification

“…for emerging risks: rising ocean temperatures impacts metabolism of toxins in oyster Warm temperature acclimation impacts metabolism of paralytic shellfish toxins from Alexandrium minutum in commercial oysters Farrell, 2015. Possibly relevant as seen by TNO experts: nano-and microplastics Ingestion of Nanoplastics and Microplastics by Pacific Oyster Larvae.…”