Z. Amzil et al., Domoic acid accumulation in French shellfish in relation to toxic species of Pseudo-nitzschia multiseries and P-pseudodelicatissima, TOXICON, 39(8), 2001, pp. 1245-1251
Within the French phytoplankton monitoring network (REPHY), domoic acid (DA
), the toxin responsible for amnesic shellfish poisoning, was first detecte
d in samples collected in 1998. Toxin analysis by the official method [liqu
id chromatography with diode array detection (LC/DAD)] was performed when P
seudo-nitzschia cell concentration was greater than 1.0 X 10(5) cells/l. LC
/DAD results obtained in 1999 and 2000 showed increased DA accumulation in
bivalves sampled at different sites along French coasts. The toxin maximum
in 1999 was 3.2 mug DA/g of whole tissue, whereas the levels in 2000 (53 mu
g) were above the sanitary threshold (20 mug DA/g tissue). Phytoplankton sa
mples collected during blooms were observed by both light and scanning elec
tron microscopy (SEM). Identification of phytoplankton species by SEM analy
ses confirmed the presence of two known DA-producing species. P. pseudodeli
catissima and P. multiseries. LC/DAD results for a mass culture of P. multi
series indicated that this species: was involved in DA accumulation in Fren
ch shellfish. (C) 2001 Elsevier Science Ltd. All rights reserved.