In recent years, both field observations and laboratory studies have confirmed that the gas-phase precursors of SOAs include volatile organic compounds (VOCs), intermediate volatile organic compounds (IVOCs), and semi-volatile organic compounds (SVOCs). Based on the semi-empirical saturation concentration (C*) of the volatility basis set (VBS), it is considered that compounds with a C* \(>\) 10\({}^{6}\)\(\mu\)g m\({}^{-3}\) are VOCs, compounds with 10\({}^{3}\)\(\mu\)g m\({}^{-3}\) < C* \(<\) 10\({}^{6}\)\(\mu\)g m\({}^{-33}\) are IVOCs, and compounds with 1 \(\mu\)g m\({}^{-3}\) < C* \(<\) 10\({}^{2}\)\(\mu\)g m\({}^{-3}\) are SVOCs. The saturated vapor concentrations, i.e., volatility, of IVOCs are in between those of VOCs and SVOCs, with volatility ranges comparable to C\({}_{12}\)-C\({}_{22}\) n-alkanes [7,8]. IVOCs typically exist in a gaseous state at ordinary temperature, but can also be partially present in the particulate phase. They can participate in particulate-phase reactions through gas-particle partitioning to form species with lower volatility [7,9]. The composition of IVOCs is highly complex. Limited by the existing technological means, only some compositions, such as n-alkanes and polycyclic aromatic hydrocarbons (PAHs), have been identified, while a large number of compositions have not yet been identified at the molecular level, including numerous cycloalkanes and branched alkanes. There is a paucity of reports on these unresolved complex mixtures (UCMs) [10,11]. Research on IVOCs is becoming increasingly multidimensional and refined. In regard to field observations, the focus of the research is on accurately calculating the emissions of IVOCs and deeply analyzing their pollution sources, in order to comprehensively understand their actual performance in the atmospheric environment [12]. In laboratory simulations, the oxidation pathways, product compositions, yields, and yield modifiers of IVOCs in the formation of SOAs have been focused on, striving to reveal the complex reaction mechanisms of IVOCs [13,14]. In model simulations, the introduction of IVOCs-related parameters has significantly enhanced the accuracy of atmospheric simulations, providing a strong theoretical basis for in-depth analysis of the pathways and contribution ratios of IVOCs during the SOA formation process [12]. In terms of environmental health, research has focused on assessing the exposure levels of IVOCs in the population and systematically evaluating potential health risks, with the goal of providing a scientific basis for public health protection [15]. Meanwhile, new detection methods are continuously emerging (such as Comprehensive Two-dimensional Gas Chromatography, GC\(\times\)GC) to address the challenges in regard to IVOC species identification, and their precision is gradually improving [16]. Although the environmental concentrations of IVOCs are usually lower than those of routinely monitored VOCs, some IVOC compositions and their oxidation products can lead to chronic toxic effects through inhalation exposure and skin penetration. The toxicity mechanisms involve multiple pathways, including DNA damage, oxidative stress, and epigenetic regulation; therefore, the health risks should not be overlooked [15,17,18]. For instance, as a significant component in the composition of IVOCs, PAHs are recognized as one of the most important pollutants, due to their carcinogenicity, toxicity, and mutagenicity,posing a serious threat to human health [19]. Thus, conducting a health risk assessment of IVOC species can help identify high-risk IVOC species, fill the current gaps in the knowledge on IVOC pollutants, and enable more effective measures to reduce their negative impacts on public health and the ecological environment. Recent research has revealed the important role of IVOCs on environmental and human health. However, the current understanding of IVOCs remains in its infancy, due to limitations in terms of the measurement technology and insufficient research on their chemical mechanisms.