Molecular response of earthworm, Eisenia fetida to Oxybenzone (Benzophenone-3) exposure

Abstract

Benzophenone-type ultraviolet filters recently received significant attention to overlook regulatory agencies' safety potential due to their toxicological implications on humans and the environment. The present study has been carried out to explore the toxicity of Benzophenone-3 (BP-3) in earthworm Eisenia fetida. Low-level long-term exposure defiles earthworm health through elevated ROS and its detrimental impact on reproductive organs and reproduction. Based on KEGG and GO analysis, global transcriptomics reveals differentially expressed gene transcripts affecting key signaling pathways. Further validation by q-PCR showed significant upregulated expression of genes involved in stress (CuZn-SOD, CAT), metabolism (GST), reproduction and gametogenesis (ANN and Piwi-2), and endocrine (EcR) functions. Interestingly, lower concentrations of BP-3 are biologically effective in exhibiting a non-linear concentration-response pattern towards the expression of reproduction and endocrine function genes. In addition, BP-3, through soil exposure, significantly alters the gut microbiome by inducing changes in bacterial diversity, while fungal diversity remains unaffected. Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes have significantly affected phyla, whereas Ascomycota and Basidiomycota remain dominant, suggesting their potential role in metabolizing or tolerating the BP-3 contamination. The findings highlight the molecular consequences of BP-3 exposure in earthworms and indicate the broader environmental impacts of benzophenone-type organic UV filters on terrestrial biota. The information could also be helpful for chemical risk assessment in soil ecotoxicology.