Distribution of Marine Lipophilic Toxins in Shellfish Products Collected from the Chinese Market

Abstract

To investigate the prevalence of lipophilic marine biotoxins in shellfish from the Chinese market, we used hydrophilic interaction liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure levels of okadaic acid (OA), azaspiracid (AZA1), pectenotoxin (PTX2), gymnodimine (GYM), and spirolide (SPX1). We collected and analyzed 291 shellfish samples from main production sites along a wide latitudinal transect along the Chinese coastline from December 2008 to December 2009. Results revealed a patchy distribution of the five toxins and highlighted the specific geographical distribution and seasonal and species variation of the putative toxigenic organisms. All five lipophilic marine biotoxins were found in shellfish samples. The highest concentrations of OA, AZA1, PTX2, GYM, and SPX1 were 37.3, 5.90, 16.4, 14.4, and 8.97 μg/kg, respectively. These values were much lower than the legislation limits for lipophilic shellfish toxins. However, the value might be significantly underestimated for the limited detection toxins. Also, these toxins were found in most coastal areas of China and were present in almost all seasons of the year. Thus, these five toxins represent a potential threat to human health. Consequently, studies should be conducted and measures should be taken to ensure the safety of the harvested product.

Association of the Toxigenic Dinoflagellate Alexandrium ostenfeldii With Spirolide Accumulation in Cultured Mussels (Mytilus galloprovincialis) From Northwest Mexico

“…In Catalonia, NW Mediterranean Sea, 2-16 µg kg −1 of 13-desmethyl spirolide C was detected in mussels and oysters (García-Altarez et al, 2014). In shellfish samples from the Chinese coast the highest concentration of 13-desmethyl spirolide C was 8.96 µg kg −1 (Wu et al, 2015) and in Norwegian blue mussels the concentration of this toxin reached 226 µg kg −1 (Rundberger et al, 2011). The concentration of this spirolide previously reported in mussels from TSB was higher during the year 2012 (3 µg kg −1 ) (García-Mendoza et al, 2014) than recorded in this present study (1.05 µg kg −1 ).…”

Simultaneous detection of three biotoxins causing diarrhetic shellfish poisoning (okadaic acid, dinophysistoxin-1, dinophysistoxin-2) in oyster by LC-MS/MS

“…To extract toxins from shellfish matrix, many studies have used methanol 17,19,20 or methanol-water mixture at different composition 21 and proved that these solvents were efficient for extracting OA and DTXs from shellfish tissues. However, the volume of solvent used for extraction was quite important, up to 10 ml per g of shellfish tissue 17,19 , leading to a significant dilution of toxin concentrations comparing to original levels in shellfish.…”

“…For analyzing OA, DTX-1 and DTX-2 by mass spectrometry, the most common ionization technique was electrospray ionization (ESI) in both positive mode (ESI + ) 22 and, negative mode (ESI -) 17,20,[23][24][25] , between them ESIwas more commonly used. In ESImode, MRM detection was applied with [M-H]precursor ion of toxin (m/z 803 with OA and DTX-2 and m/z 817 with DTX-1) and product ions with m/z 113, 255 and 563 being used for identification of toxins, and quantitative determination was done with product ion m/z 255 17,20,[23][24][25] .…”

“…For analyzing OA, DTX-1 and DTX-2 by mass spectrometry, the most common ionization technique was electrospray ionization (ESI) in both positive mode (ESI + ) 22 and, negative mode (ESI -) 17,20,[23][24][25] , between them ESIwas more commonly used. In ESImode, MRM detection was applied with [M-H]precursor ion of toxin (m/z 803 with OA and DTX-2 and m/z 817 with DTX-1) and product ions with m/z 113, 255 and 563 being used for identification of toxins, and quantitative determination was done with product ion m/z 255 17,20,[23][24][25] . The use of ESImode was preferred because studies have showed that at negative ion mode, OA and DTX-1, DTX-2 all gave precursor ion [M-H] with high intensity, and the [M-H]ion of OA (m/z 803) and DTXs (m/z 817 for DTX-1 and m/z 803 for DTX-2) all produced product ions having m/z 563, 255, and 113, a characteristics highly specific for DSP toxins, in which product ion m/z 255 had highest intensity, suitable for quantitative application 26,27 .…”

“…In ESImode, because [M-H]ion and its product ions of OA and DTX-2 having the same value of m/z, these two toxins can not be distinguished by MS/MS detection and must be separate by UPLC process. The separation of OA and DTXs were done mainly by reverse phase liquid chromatography on C18 column 17,22,25 , C8 column 23,24 , with mobile phase using mixture of acetonitrile and water containing ammoniac at basic pH 17,23 or a mixture of acetonitrile and water at acidic pH containing formic acid 20,22 or formic acid and ammonium formate 17,24,28 . In this study, a conventional HPLC column (packed with 5 µm particles) and a UPLC column (packed with 1.8 µm particles), both contained C18 stationary phase, were tried in the preliminary study with mobile phase consisted of acetonitrilewater containing formic acid and ammonium formate.…”