DIN EN 14526:2017-04

This standard specifies a method for the quantitative determination of saxitoxin and DC-saxitoxin in mussels. The toxins of the saxitoxin group are highly neurotoxic substances that are formed by marine algae and accumulate in mussels. European Council Directive 91/493/EEC of July 22, 1991 "laying down the health conditions for the production and the placing on the market of fishery products" specifies a maximum permitted level of saxitoxin. In order to ensure consumer health protection, it is therefore urgently necessary to test the maximum levels using suitable, validated procedures. The method described in DIN EN 14526 was validated on various mussel species with saxitoxin contents of 22 µg/kg to 1 048 µg/kg in several interlaboratory tests. In addition to saxitoxin, the other toxins in this group were also examined in these interlaboratory tests: decarbamoyl saxitoxin (dcSTX), neosaxitoxin (NEO), decarbamoyl neosaxitoxin (dcNEO), gonyautoxin 1 and 4 (GTX1,4; sum of the isomers), gonyautoxin 2 and 3 (GTX2,3; sum of isomers), gonyautoxin 5 (GTX5, also called B1), gonyautoxin 6 (GTX6, also called B2), decarbamoyl-gonyautoxin 2 and 3 (dcGTX2,3; sum of isomers), N-sulfocarbamoyl-gonyautoxin 1 and 2 (C1,2; sum of isomers). Paralytic Shellfish Poisoning (PSP) toxins are extracted from shellfish tissue homogenate by heating with acetic acid. After centrifugation the supernatant is purified by solid phase extraction (SPE) using a C18 clean-up cartridge. It is analysed by HPLC after oxidation with periodate or peroxide with fluorescence detection. Most toxins (STX, C1,2, GTX5 (B1), dcSTX, GTX2,3 and dcGTX2,3) can be quantified after SPE-C18 clean-up. For the quantitative determination of N-hydroxylated toxins, a fractionation by SPE-COOH clean-up is necessary because the oxidation products of some PSP toxins (NEO and GTX6 (B2), GTX1,4 and C3,4) are identical. This standard has been prepared by Technical Committee TC 275 "Food analysis - Horizontal methods" (secretariat: DIN, Germany) of the European Committee for Standardization (CEN) after detailed preliminary work by Working Group 14 "Marine biotoxins". The responsible German working committee is Working Group NA 057-01-03-01 AK "Algentoxine" ("Algal toxins") of Working Committee NA 057-01-03 AA "Biotoxine" ("Biotoxins") DIN Standards Committee Food and Agricultural Products (NAL).