Multi-year assessment of paralytic shellfish toxins in hard clam species along the coastline of Jiangsu Province, China

Abstract

Paralytic shellfish toxins (PSTs) are notorious neurotoxins that threaten public health and food safety worldwide. Although PST monitoring programs have recently been established throughout China, the profiles and variation of PSTs in important commercial clams (e.g., Mactra veneriformis, Ruditapes philippinarum, and Meretrix meretrix) along the Jiangsu Province coastline remain largely unexplored. In this study, a validated hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC-MS/MS) method was used to examine PST profiles and levels in 540 clam samples from natural production areas along Jiangsu Province coastline during 2014–2016. Although the PST levels (≤6.38 μg saxitotoxin equivalents (eq)/kg) were consistently below European Union regulatory limits (≤800 μg saxitotoxin eq/kg) during this time period, saxitotoxin, decarbamoylsaxitotoxin, and gonyautoxins 1 and 4 were detected, and nearly 40% of the samples were saxitotoxin-positive. The PST levels also varied significantly by seasons, with peak values observed in May during 2014–2016. This is the first systematic report of PSTs in clams from Jiangsu Province, and additional research and protective measures are needed to ensure the safety of clams harvested in this area.