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most prevalent in blue mussel (Mytilus galloprovincialis), followed by the European
flat oyster (Ostrea edulis), the Mediterranean scallop (Pecten jacobaeus) and proteus scallop (Flexopecten proteus) (Ujevic et al. 2010). The presence of domoic acid
in tissues of octopus (Eledone cirrhosa, E. moschata species, Octopus vulgaris)
(Costa et al. 2004, 2005a), cuttlefish (Sepia officinalis) (Costa et al. 2005b) and
swimming crab (Polybius henslowii) (Costa et al. 2003) collected from the
Portuguese coast showed that toxin was transported through the sea food chain.
Novaczek et al. (1992) reported that industrial depuration may provide a means
of removing domoic acid toxin from blue mussels (Mytilus edulis). These researchers transported mussels containing up to 50 μg/g domoic acid from a Prince Edward
Island estuary into controlled laboratory conditions. They found that 50% of toxin
is eliminated within 24 h.
Although cooking due to the heat stability of domoic acid does not destroy the
toxin, it has been reported that normal home cooking processes such as boiling and
steaming can reduce the amount of DA in shellfish due to the partial leakage of the
toxin into the cooking liquids (Andjelkovic et al. 2012). The effect of cooking on
the concentration of domoic acid in the Manila clam (Ruditapes philippinarum) and
cockle (Cerastoderma edule) was investigated. In that study, these molluscs were
cooked by steaming and boiling. They found that cooking provided different effect
for these two species, a significant part of its domoic acid content was lost by cooking in the cockle, while the clam did not. The authors stated that cooking affects the
toxin concentration in bivalves in a way that is species specific (Vidal et al. 2009).
It has been determined that the cooking process provides more than 50% reduction
in the concentration of DA in swimming crab (Polybius henslowii) (Costa et al.
2003). Reboreda et al. (2010) studied on reduction of ASP in scallops. They tried
different elimination methods including evisceration, thermal processing, freezing
and their combination. They found that the most effective method to reduce toxin
level to the legal limit is ablation of the hepatopancreas. It was found insignificant
reduction with the other methods.
5.3.4 Neurotoxic Shellfish Poisoning (NSP)
Neurotoxic Shellfish Poisoning is a little common intoxication, which has not been
documented as a fatal intoxication in humans, and results from consumption of molluscan shellfish contaminated with brevetoxins (Zaccaroni and Scaravelli 2008).
NSP is caused by a group of toxins, the brevetoxins (BTXs), secreted by marine
dinoflagellates of the genus Karenia. The main symptoms of NSP are headaches,
dizziness, muscle and joint pain and difficulty in breathing, and full recovery generally occurs within 48 h (Gosling 2015). In the first one symptom are both neurological and gastro-intestinal and appear within 1–3 h after mussels’ ingestion.
Neurological syndrome includes paraesthesia of area around the mouth, the face
and throat, muscular ache, ataxia, inversion of thermal perception, bradycardia,
mydriasis. Gastro-intestinal syndrome includes abdominal pain, nausea, diarrhoea.
5 Shellfish Safety
most prevalent in blue mussel (Mytilus galloprovincialis), followed by the European
flat oyster (Ostrea edulis), the Mediterranean scallop (Pecten jacobaeus) and proteus scallop (Flexopecten proteus) (Ujevic et al. 2010). The presence of domoic acid
in tissues of octopus (Eledone cirrhosa, E. moschata species, Octopus vulgaris)
(Costa et al. 2004, 2005a), cuttlefish (Sepia officinalis) (Costa et al. 2005b) and
swimming crab (Polybius henslowii) (Costa et al. 2003) collected from the
Portuguese coast showed that toxin was transported through the sea food chain.
Novaczek et al. (1992) reported that industrial depuration may provide a means
of removing domoic acid toxin from blue mussels (Mytilus edulis). These researchers transported mussels containing up to 50 μg/g domoic acid from a Prince Edward
Island estuary into controlled laboratory conditions. They found that 50% of toxin
is eliminated within 24 h.
Although cooking due to the heat stability of domoic acid does not destroy the
toxin, it has been reported that normal home cooking processes such as boiling and
steaming can reduce the amount of DA in shellfish due to the partial leakage of the
toxin into the cooking liquids (Andjelkovic et al. 2012). The effect of cooking on
the concentration of domoic acid in the Manila clam (Ruditapes philippinarum) and
cockle (Cerastoderma edule) was investigated. In that study, these molluscs were
cooked by steaming and boiling. They found that cooking provided different effect
for these two species, a significant part of its domoic acid content was lost by cooking in the cockle, while the clam did not. The authors stated that cooking affects the
toxin concentration in bivalves in a way that is species specific (Vidal et al. 2009).
It has been determined that the cooking process provides more than 50% reduction
in the concentration of DA in swimming crab (Polybius henslowii) (Costa et al.
2003). Reboreda et al. (2010) studied on reduction of ASP in scallops. They tried
different elimination methods including evisceration, thermal processing, freezing
and their combination. They found that the most effective method to reduce toxin
level to the legal limit is ablation of the hepatopancreas. It was found insignificant
reduction with the other methods.
5.3.4 Neurotoxic Shellfish Poisoning (NSP)
Neurotoxic Shellfish Poisoning is a little common intoxication, which has not been
documented as a fatal intoxication in humans, and results from consumption of molluscan shellfish contaminated with brevetoxins (Zaccaroni and Scaravelli 2008).
NSP is caused by a group of toxins, the brevetoxins (BTXs), secreted by marine
dinoflagellates of the genus Karenia. The main symptoms of NSP are headaches,
dizziness, muscle and joint pain and difficulty in breathing, and full recovery generally occurs within 48 h (Gosling 2015). In the first one symptom are both neurological and gastro-intestinal and appear within 1–3 h after mussels’ ingestion.
Neurological syndrome includes paraesthesia of area around the mouth, the face
and throat, muscular ache, ataxia, inversion of thermal perception, bradycardia,
mydriasis. Gastro-intestinal syndrome includes abdominal pain, nausea, diarrhoea.
5 Shellfish Safety