Environmental RNA (eRNA), derived from living organisms, pathogens, and double-stranded RNA (dsRNA)-based biopesticides, is becoming increasingly important in the contexts of environmental monitoring, biosafety, and environmental remediation. Although RNA is considered an unstable molecule, its stability can increase through interactions with solid surfaces and porous materials, thereby influencing its transport, accumulation, and bioavailability in the environment. This review summarizes the current state of knowledge regarding RNA adsorption onto advanced porous materials, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), mesoporous silica, carbon-based materials, biochar, porous polymers, and hybrid materials. It outlines RNA binding mechanisms—such as electrostatic interactions, hydrogen bonding, π–π interactions, and metal-ion complexation—as well as the influence of environmental factors such as pH, ionic strength, and the presence of organic substances. Methods for studying RNA adsorption, adsorbent regeneration and reusability, and potential applications in wastewater treatment, environmental monitoring, and the mitigation of the spread of biologically active RNA are also discussed. This review highlights the persistent gap between laboratory-scale adsorption studies and the real-world deployment of RNA-capturing materials in complex environmental matrices and proposes an integrative framework tracing how RNA type and material properties jointly shape adsorption mechanisms and, in turn, biosafety outcomes.