Occurrence and variation of lipophilic shellfish toxins in phytoplankton, shellfish and seawater samples from the aquaculture zone in the Yellow Sea, China

Meihui Li; Geng Sun; Jiangbing Qiu; Aifeng Li

doi:10.1016/j.toxicon.2016.12.009

Occurrence and variation of lipophilic shellfish toxins in phytoplankton, shellfish and seawater samples from the aquaculture zone in the Yellow Sea, China

Toxicon. 2017 Mar 1:127:1-10. doi: 10.1016/j.toxicon.2016.12.009. Epub 2016 Dec 22.

Authors

Meihui Li¹, Geng Sun¹, Jiangbing Qiu¹, Aifeng Li²

Affiliations

¹ College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
² College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China; Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China. Electronic address: lafouc@ouc.edu.cn.

PMID: 28012801
DOI: 10.1016/j.toxicon.2016.12.009

Abstract

Lipophilic shellfish toxins (LSTs) produced by diverse microalgae have become a potential threat to the marine aquaculture industry in coastal regions throughout the world. In this study, phytoplankton, scallop, and seawater samples were collected and monitored in the aquaculture zone of Liuqing Bay located in the coast of Qingdao, Yellow Sea, in 2014 and 2015. Dissolved LSTs in seawater were adsorbed by solid phase adsorption toxin tracking (SPATT) bags and solid phase extraction (SPE) cartridges, respectively. PTX2 was found to be the predominant LSTs, while OA and DTX1 were detected at trace levels in the three species of Dinophysis and Phalacroma genera picked from the investigation zone. The highest quota of PTX2 occurred in D. fortii (0.28 pg cell^-1), followed by D. acuminata complex (0.08 pg cell^-1) and P. rotundatum (=D. rotundata) (0.02 pg cell^-1). PTX2 (nd∼5.7 μg kg^-1), OA (nd∼2.8 μg kg^-1) and DTX1 (nd∼1.6 μg kg^-1) were also observed in cultivated scallops, but in addition to the former, PTX2sa, 7-epi-PTX2sa and an isobaric form of DTX1 suspected as DTX1b were also found in the SPATT bags. The isobaric compound of DTX1 only appeared in the SPATT bags deployed in field samples of seawater. A significant higher quantity of OA was adsorbed by SPATT bags compared to DTX1, although similar concentrations of both toxins were adsorbed by SPE cartridges from the aquaculture zone. AZA2 was also found in the concentrated phytoplankton cells, which demonstrated that AZA-producing microalgae were present in this investigated area. The variation in concentrations of PTX2 adsorbed by SPATT bags could reflect the change of Dinophysis density in seawater, but there was a time lag behind the peaks of Dinophysis density. Comparative results did not support the SPATT technology as a useful warning tool for toxic algal blooms and toxin accumulation in bivalves. The data suggest that the contamination of LSTs was prevalent in the coast of Qingdao and the environmental behavior of LSTs should be explored further.

Keywords: Chlamys farreri; Dinophysis spp.; LC-MS/MS; Lipophilic shellfish toxins (LSTs); Solid phase adsorption toxin tracking (SPATT).

MeSH terms

Animals
Aquaculture
China
Dinoflagellida / chemistry*
Environmental Monitoring
Marine Toxins / analysis*
Pectinidae / chemistry*
Phytoplankton / chemistry*
Seawater
Shellfish / analysis*
Solid Phase Extraction / methods

Substances

Marine Toxins