Changes in metabolic profiles of amphipods Allorchestes compressa after acute exposures to copper, pyrene, and their mixtures

Amphipods are ideal indicators for biomonitoring and ecotoxicological studies of environmental contaminants because they are extensively distributed in aquatic environments, are easy to collect and are important in nutrient cycling. Marine amphipods (Allorchestes compressa) were exposed to two concentrations of copper and pyrene, and their mixtures, for 24 and 48 h. Changes in polar metabolites were assessed using Gas Chroma-tography Mass Spectrometry (GC-MS)-based untargeted metabolomics. Generally, limited metabolite changes were observed for copper and pyrene single exposures (eight and two significant metabolites, respectively), while 28 metabolites had changed following exposures to mixtures. Furthermore, changes were mainly observed after 24 h but had seemingly returned to control levels after 48 h. Multiple types of metabolites were affected including amino acids, Tricarboxylic acid (TCA) cycle intermediates, sugars, fatty acids, and hormones. This study highlights the sensitivity of metabolomics in assessing the impacts of low concentrations of chemicals compared to traditional ecotoxicological endpoints.

Automated summary

Amphipods are widely distributed in aquatic environments and play an important role in nutrient cycling, making them ideal indicators for biomonitoring and ecotoxicological studies. In this study, marine amphipods were exposed to copper, pyrene, and their mixtures for different durations, and changes in polar metabolites were assessed using GC-MS-based untargeted metabolomics. Limited metabolite changes were observed for single exposures, while mixtures had a greater impact on metabolites. The results highlight the sensitivity of metabolomics in assessing the effects of low concentrations of chemicals compared to traditional ecotoxicological endpoints.