Uncontrolled Disposal of Plastic Agrochemical Packaging: Double-Trouble Ecotoxicological Effects in Soil and Water

The widespread use of agrochemicals, including inorganic and organic pesticides and fungicides, has contributed to the persistence of hazardous residues in agricultural environments, particularly through their accumulation in plastic packaging and containers. High-density polyethylene (HDPE), polypropylene (PP), and other polymer types commonly employed for agrochemical storage and transport retain significant quantities of active substances even after standard rinsing procedures. This phenomenon raises concerns over improper disposal practices, environmental contamination, and potential ecotoxicological impacts. Recent studies demonstrate that both inorganic and organic pesticide residues exhibit strong interactions with plastic polymers, influenced by factors such as polymer chemistry, surface aging, pH, ionic strength, and dissolved organic matter. These interactions not only delay degradation but also facilitate secondary release into soils and aquatic systems, where they may impair soil microorganisms, alter plant physiology, and disrupt aquatic food webs, including phytoplankton, fish, and microbial assemblages. Despite regulatory frameworks and container management schemes in some regions, major knowledge gaps remain regarding the long-term fate of pesticide residues on plastics, their transfer to ecosystems, and cumulative effects on agroecosystem sustainability. This review synthesizes current evidence on the chemical characteristics of pesticide residues in plastic packaging, their environmental mobility, and ecotoxicological effects. It further identifies urgent research needs, including long-term field assessments of polymer–pesticide interactions, improved recycling technologies, and the development of safer container designs. Effective management strategies, coupled with strengthened international stewardship programs, are essential to reduce risks to environmental health, agricultural productivity, and human safety.