Table 3.

Sample information from continental Portugal. TTXs analogues in positive samples analyzed by high resolution mass spectrometry (HRMS) and quantified by MRM mode.

Sampling Date	Sampling Site	Sample	Species	Trophic Level [Ref]	Edible	Code	Suspicious TTXs	RT (min)	Elemental Composition	Theoretical m/z	Experimental m/z	Error (mDa)	TTX eq (µg/Kg)
September 2011	Porto Côvo	Limpet	Patella depressa	Grazer [27]	Yes	225	11-oxoTTX	7.2	C11H17N3O9	336.1038	336.1000	−3.8	<LOQ
		Gastropod	Phorcus lineatus	Grazer [28]	Yes	226	trideoxyTTX	7.7	C11H17N3O5	272.1241	272.1232	−0.9	<LOQ
October 2011	Pedra de Jacó	Sea-urchin	Echinus esculentus	Grazer [29]	Yes	229_2	11-oxoTTX	7.2	C11H17N3O9	336.1038	336.1020	−1.8	<LOQ
	Ovar	Gastropod	Charonia lampas	3rd Level Predator [30]	Yes	232_2	trideoxyTTX	7.7	C11H17N3O5	272.1241	272.1230	−1.1	<LOQ
						232_3	trideoxyTTX	7.7	C11H17N3O5	272.1241	272.1251	1.0	<LOQ
November 2011	Memória	Gastropod	Nucella lapillus	1st Level Predator [27]	Yes	236	trideoxyTTX	7.7	C11H17N3O5	272.1241	272.1239	−0.2	<LOQ
			Phorcus lineatus	Grazer [28]	Yes	239	11-oxoTTX	7.2	C11H17N3O9	336.1038	336.1000	−3.8	<LOQ
			Gibbula umbilicalis	Grazer [28]	Yes	240	trideoxyTTX	7.7	C11H17N3O5	272.1241	272.1238	−1.1	<LOQ