Identification of organic contaminants accumulated in mollusc by means of High Resolution Mass Spectrometry

Abstract

Chemical contamination of estuarine and coastal areas has negative implications for the environment and may also pose a risk for human health through the ingestion of contaminated fish and shellfish. Therefore, as part of the XENOMETABOLOMIC project, the present work aims to identify priority mixture of contaminants accumulated in wild mussels from Ebro Delta (Mytilus galloprovincialis) that may be of relevance for future monitoring and regulation. Moreover, it intends to elucidate potential differences in contamination patterns between the two Ebro Delta bays, Alfacs and Fangar, and provides data of the occurrence and distribution of the contaminants in mussels from each bay. For this purpose, a previously developed analytical method was used, based on ultra-high performance liquid chromatography (UHPLC) coupled to high resolution mass spectrometry (HRMS). Sample extraction and purification were performed by using QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) methodology. The analysis reveals the presence of 11 out of 23 compounds included in the analytical method, comprising organonitrogen pesticides, herbicides, endocrine disruptor compounds (EDCs), and pharmaceutically active compounds (PhACs). Their concentrations in mussels ranged from 0.19 ng/g dry weight (dw) of desethylatrazine to a maximum concentration of 19.25 ng/g dw of methylparaben. The total concentrations of contaminants (expressed as the sum of their single concentrations) at every sampling point did not exceed 25 ng/g dw. The levels found in the present work are far below the maximum residues limits (MRL) established by the European Union, so that a potential risk to human health through mussel ingestion is unlikely to happen