One health is a holistic approach that recognizes people's health is closely linked to the health of animals and the environment. Environmental chemistry is integral to the One Health paradigm, providing critical insights into how pollutants and chemicals in our surroundings impact ecosystems, wildlife, and human populations. Persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and per- and polyfluoroalkyl substances (PFAS), are resistant to environmental degradation and accumulate in the food chain, posing significant risks to human, animal, and ecological health. Environmental chemistry helps us understand the mechanisms of POPs' persistence and dispersion, their transformation in various environmental media, and their exposure pathways to living organisms. For instance, the accumulation of POPs in marine ecosystems can lead to adverse effects on aquatic life, impacting human health through consuming contaminated seafood. Additionally, research in environmental chemistry has shown that POPs can disrupt endocrine systems, leading to reproductive and developmental problems in animals and humans. The field of environmental chemistry is also instrumental in understanding the effects of persistent organic pollutants (POPs) through adverse outcome pathways (AOPs), which provides the structured framework for linking molecular-level interactions of POPs with biological pathways, ultimately leading to adverse health effects. For example, exposure to POPs can initiate a cascade of events at the cellular level, such as receptor binding and gene expression changes, which may result in endocrine disruption and reproductive issues in wildlife and humans. This talk will explore the role of environmental chemistry in interdisciplinary collaborative efforts to tackle complex environmental health challenges.