# Emerging Contaminants in Raw and Cooked Marine Mussels: The QuEChERS Approach Combined With High‐Performance Liquid Chromatography Coupled With Tandem Mass Spectrometry

## TL;DR

This study uses a new method to detect emerging contaminants in raw and cooked mussels, finding higher contaminant levels after boiling.

## Contribution

This is the first study to investigate how cooking affects concentrations of emerging contaminants in mussels.

## Key findings

- Caffeine was the most frequently detected contaminant in mussel samples.
- Boiled mussel samples showed consistently higher contaminant concentrations than raw samples.
- UV filters were commonly found, likely due to increased sunscreen use during the sampling period.

## Abstract

Mussel aquaculture has experienced substantial growth in recent decades, with global production exceeding 2.17 megatons (live weight), more than doubling since the early 21st century. Representing nearly 94% of the total mussel production, aquaculture plays a crucial economic and ecological role. Mussels accumulate xenobiotics through their filter‐feeding behaviour, providing valuable insights into potential human exposure to the contaminants. However, the high lipid and protein content in their tissue can introduce analytical challenges, requiring rigorous clean‐up procedures to mitigate matrix effects. Herein, we applied a QuEChERS‐based extraction method coupled with high‐performance liquid chromatography‐tandem mass spectrometry (HPLC–MS/MS) to investigate the occurrence of emerging contaminants (ECs) in raw and boiled
Mytilus galloprovincialis
samples. Samples were collected from three aquaculture farms supplying mussels to fish markets in Liguria (Italy), aiming to provide a representative overview of contamination across different geographical sources. A total of 36 samples were analysed, detecting ECs in 26 samples. Caffeine was the most frequently detected contaminant, consistent with its widespread consumption. Additionally, UV filters were also commonly found in the samples, likely due to the sampling period at the end of summer, when sunscreen use is highest. This is the first study to investigate the impact of cooking on the concentrations of different classes of ECs in mussels, reflecting real consumption conditions. Box and whisker plots revealed consistently higher contaminant concentrations in boiled samples, suggesting that thermal processing may influence contaminant release. This study aims to offer insights into contaminants distribution and preliminary information for human exposure assessment of potential risks to human health.