Anthropogenic Chemical Stressors and Host Defence in Wild Populations

Anthropogenic chemical stressors, including pesticides (insecticides and fungicides), per- and polyfluoroalkyl substances (PFAS), microplastics, and other emerging environmental contaminants, are increasingly pervasive in natural ecosystems, with growing evidence that they compromise host defence across taxa. Understanding how these compounds affect the full spectrum of host protection, from physical and chemical barriers to cellular and humoral immune responses, is critical to predicting disease susceptibility and population resilience in a changing world.Host defence in animals is a multilayered process encompassing physical and chemical barriers (cuticle, skin, mucus layers, gut epithelium), host–microbiota interactions, and innate and adaptive immune responses. Chemical contaminants can disrupt this system at multiple levels: degrading barrier integrity, altering microbial communities, impairing leukocyte function and cytokine signalling, and modulating antibody production, often with knock-on effects for growth, reproduction, and survival. Because exposure and its consequences are best understood under ecologically realistic conditions, studies of wild and semi-natural populations are especially valuable, and comparative approaches across vertebrate and invertebrate systems can reveal both shared vulnerabilities and lineage-specific responses to chemical stress.This Research Topic aims to explore how anthropogenic chemical stressors reshape host defence in wild hosts, spanning barrier function, microbiota, and immune responses, within an ecological and comparative immunology framework. We welcome contributions that examine how pesticides, PFAS, microplastics, and related contaminants affect host protection across species, and that link mechanistic findings to ecological and evolutionary consequences.We welcome original research articles, reviews, and perspectives addressing, but not limited to, the following themes:- Effects of pesticides, PFAS, microplastics, and other emerging contaminants on host defence in wild and semi-natural populations- Contaminant-driven disruption of physical and chemical barrier defences (cuticle, skin, mucus, gut epithelium)- Chemical stressor impacts on host–microbiota interactions and their consequences for protection- Immunotoxicological effects of environmental contaminants on cellular and humoral immune responses- Comparative vulnerability and resilience to chemical stressors across vertebrate and invertebrate systems- Trade-offs between contaminant-induced immune costs and growth, reproduction, or development- Ecological and evolutionary consequences of chronic low-level chemical exposure on host defence- Chemical pollution as a driver of disease susceptibility and population-level health outcomes in the wild Topic editors: Farley Silva, Ebru YILMAZ Source: https://www.frontiersin.org/research-topics/84717/anthropogenic-chemical-stressors-and-host-defence-in-wild-populations