Study of the bile proteome of Atlantic cod (Gadus morhua): Multi-biological markers of exposure to polycyclic aromatic hydrocarbons

• This study reports the characterization of the Atlantic cod bile proteome.
• This study aims to develop analytical strategies for fish bile analysis.
• Testing to discover new sensitive markers, PAH–protein adducts, in Atlantic cod.
• Protein markers were identified using LC–MS/MS, as single biological indicators.

PAH metabolites present in bile are well-known biological markers of exposure in fish, and their investigation is recommended by the ICES (International Council for the Exploration of the Sea) and the OSPAR convention (Convention for the Protection of the Marine Environment of the North-East Atlantic) for monitoring purposes.Development of analytical strategies for fish bile is encouraged by the need for more sensitive and informative markers (e.g. capable of tracking the PAH composition of contamination sources) and strengthened by recent results in both fish genomics and proteomics. Herein, the study of the Atlantic cod bile proteome is presented. Preliminary testing for discovering new sensitive markers in the form of expressed proteins affected by PAH exposure (i.e. PAH–protein adducts) is reported. Protein markers were identified using LC–MS/MS analysis, as single biological indicators. Through multivariate analyses, the overall proteome was revealed to be a sensitive multi-biological marker of exposure to PAHs.