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All 14 pesticides showed different degrees of AhR agonistic activity, and none of the two non-agonist AhR ligand pesticides showed AhR agonistic activity, which suggests that our procedure had good robustness. Four of the pesticides were reported as AhR agonists for the first time, suggesting that these pesticides may need further toxicity assessment. In general, our procedure is a rapid, powerful and computationally inexpensive tool for predicting chemicals with AhR agonistic activity, which could be useful for environmental risk prediction and management.The plasticizer di (2-ethylhexyl) phthalate (DEHP) is becoming increasingly abundant throughout the global environment as plastic pollution becomes highly severe, especially in the ocean. The adverse effects of DEHP have garnered increasing concern as they are recognized as endocrine disruptors. However, information on the effects of DEHP in marine organisms remains limited. In this study, acute toxic effects on marine medaka (Oryzias melastigma) following DEHP exposure were investigated. Transcriptome analysis was performed on the livers of medaka exposed to DEHP for 6 and 24 h. Results showed that 1595 genes were affected in all the analyzed specimens, and several genes expressed variably according to sex. Some pathways associated with immunity, metabolism, and endocrine system were significantly enriched, with the complement system appearing to be the most affected immune pathway. Pathway enrichment indicated that, under acute DEHP exposure, the immune response of females tended to be more sensitive than that of males. In addition, ferroptosis occurred in response to DEHP exposure, which resulted in an enrichment of the ferroptosis pathway along with iron overload, an increase in malondialdehyde (MDA) and lipid peroxidation (LPO) content, and a decrease in glutathione (GSH) levels. These results indicate that a form of cell death characterized by iron-dependence occurred following DEHP exposure, but the underlying mechanism requires further analysis. This study implies that DEHP can alter some molecular regulation patterns within a short period and induce cell death through ferroptosis.Plastic pollution has become a pervasive environmental problem on a global scale, from the ocean depths to the aquatic ecosystems of the Tibetan Plateau. To date, data on plastic and microplastic occurrence in pristine ecosystems like high-mountain lakes are lacking. In this study, plastic (>5000 μm) and microplastic (10-5000 μm) levels were measured in snow at the end of the winter season (April 2020), and in water, sediment, and biological samples collected monthly (June-October 2019) during the ice-free season from the Dimon Lake, a high-mountain lake in the Carnic Alps, northeast Italy. Biological samples consisted of chironomids (Diptera, Chironomidae; n = 150) and stomach contents of Cottus gobio (n = 40). Analysis of the water, sediment, and biological samples revealed the absence of plastic and microplastics larger than 10 μm, whereas the snow samples contained microplastics of polyethylene terephthalate (PET) albeit at very low levels (0.11 ± 0.19 L-1). These results show that while the lake ecosystem could be considered unpolluted by microplastics, abundant snow precipitation in winter can trap microplastic particles that deposit on the ground. The very low levels of PET microparticles recorded in the snow samples suggest the need for further research to better understand the source of microplastic pollution in this environmental matrix.Polychlorinated biphenyls (PCBs) and dibenzo-p-dioxins and furans (PCDD/Fs) are notorious persistent organic pollutants (POPs), which may bioaccumulate through food chain and play detrimental effects to organisms even at trace levels. Quantification of PCBs and PCDD/Fs in biotic samples is a great challenge. In the present study, gas chromatography coupled to triple quadrupole mass spectrometry with an atmospheric pressure chemical ionization source (GC-(APCI)MS/MS) was studied for the isotope-dilution analysis of PCBs (mono-to deca-) and PCDD/Fs in Chinese mitten crab food webs. High-resolution mass spectrometry (HRMS) was applied for comparison. Light PCBs are compared between the two instruments for the first time. After optimization of instrument parameters, the RSDs of relative response factors of calibration curves were between 3.4% and 15.5% for PCBs and 1.7%-7.9% for PCDD/Fs. Selleck Remodelin The limits of detection were between 0.021 and 0.150 pg/mL for PCBs and 0.051-0.237 pg/mL for PCDD/Fs. PCB concentrations in crab food web samples detected by GC-(APCI)MS/MS were well correlated with those detected by HRGC/HRMS. A DiCB, 3,3'-dichlorobiphenyl (PCB11), was the dominant PCB congener in aquatic food webs. Other MoCB and DiCB congeners were also widely identified; hence, low-weight PCB congeners should arouse more concern in the future. GC-(APCI)MS/MS may become an alternative instrument satisfying the PCB and PCDD/F detection.Current guidelines tend to limit fish consumption based on mercury (Hg) or monomethylmercury (MeHg) content in fish flesh, without considering the presence of antagonist chemical elements that could modulate Hg toxicity. However, it is difficult to assess the potential for antagonistic interactions of these elements since their covariation within muscle tissues is poorly known. Here we present the first study simultaneously mapping multiple metal(oid)s (Hg, As and Se), lipids and proteins in fish fillets in order to assess the magnitude of intra-organ variability of metals and the potential for antagonistic interactions. We mapped two fish species (Striped Bass and Northern Pike) with contrasting muscular structure with respect to the presence of white, intermediate and red muscles. In individual Striped Bass muscle tissues, metals varied on average by 2.2-fold. Methylmercury and selenium covaried strongly and were related to protein content as assessed by % N; arsenic was inversely related to these elements and was associated with the lipid fraction of the muscle. In Pike, no such relationship was found because the contents in proteins and lipids were less variable. Arsenic speciation revealed that arsenobetaine and arsenolipids were the only As species in those fish species, whereas the toxic inorganic As species (As3+) was under the detection limit. Arsenobetaine was related to % N, whereas arsenolipids covaried with % lipids. Elemental associations found with muscle lipids and proteins could help explain changes in bioaccumulation patterns within and between individuals with potential implications on fish toxicology, biomonitoring and human consumption guidelines.