Traditional ecotoxicology primarily investigates pollutant toxicity through physiological, biochemical, and single-molecular indicators. However, the limited data obtained through this approach constrain its application in the mechanistic analysis of pollutant toxicity. Omics technologies have emerged as a major research focus in recent years, enabling the comprehensive and accurate analysis of biomolecular-level changes. The integration of multi-omics technologies can holistically reveal the molecular toxicity mechanisms of pollutants, representing a primary emphasis in current toxicological research. This paper introduces the fundamental concepts of genomics, transcriptomics, proteomics, and metabolomics, while reviewing recent advancements in integrated omics approaches within aquatic toxicology. Furthermore, it provides a reference framework for the implementation of multi-omics strategies in ecotoxicological investigations. While multi-omics integration enables the unprecedented reconstruction of pollutant-induced molecular cascades and earlier biomarker discovery (notably through microbiome–metabolome linkages), its full potential requires experimental designs, machine learning-enhanced data integration, and validation against traditional toxicological endpoints within environmentally relevant models.

In recent years, China has determined the national goal of “developing national environmental criteria”, thereby promoting the rapid development of environmental quality criteria research in China. In 2017, the Ministry of Ecology and Environment of China (MEEC, formerly the Ministry of Environmental Protection of China) issued the technical guideline for deriving water quality criteria (WQC) for protection of freshwater organisms (HJ 831-2017), and in 2022, they organized the guideline revision and issued an updated version (HJ 831-2022). The primary contents of the revision included the following. The minimum toxicity data requirements were upgraded from 6 to 10, and the species mean toxicity value was replaced by the same effect toxicity value for the criteria calculation. It is now required that the tested organisms must be distributed in China’s natural fresh waters, and the toxicity data of non-native model species will no longer be used. The list of freshwater invasive species in China that cannot be used as test species was added into the guideline. The acute/chronic ratio (ACR) method for the criteria derivation and the extreme value model were deleted, and the provisions for testing the toxicity data distribution were also deleted. The exposure time of the toxicity test of various tested organisms was refined, and the priority of the toxicity data was clearly specified. This paper introduces the framework and specific technical requirements of HJ 831-2022 in detail, including data collection, pre-processing of toxicity data, criteria derivation, fitting models, and quality control. This introduction is helpful for international peers to understand the latest research progress of China’s WQC.

This editorial introduces the Special Issue “Effects of Environmental Organic Pollutants on Environment and Human Health: The Latest Updates”

Chitons, ancient polyplacophoran mollusks, are ideal models for studying biomineralization evolution due to their conserved morphology since the Cambrian. This study investigates the matrix proteins in shell plates and spicules of Acanthochitona rubrolineata using liquid chromatography–tandem mass spectrometry. By extracting proteins from 30 individuals and using proteomic method, we identified 26 soluble proteins and 22 insoluble proteins in the shell plates and 25 insoluble proteins, and found domains such as von Willebrand factor type A, chitin-binding, ferritin, and cadherin. These domains, prevalent in molluscan biominerals, suggest conserved roles in organic matrix formation. Despite genomic dynamism, the conservation of key domains across species highlights a core biomineralization mechanism. Notably, eight of the shell proteins and eight of the spicule proteins were homologous between A. rubrolineata and chiton Acanthopleura loochooana, indicating functional conservation. Phylogenetic analysis further supported the evolutionary significance of these domains in chitons. The study advances understanding of biomineralization in Polyplacophora, emphasizing the interplay between morphological stasis and molecular evolution.