Re-engineering of nanofertilizers for sustainable agriculture: synthesis, mechanistic insights, toxicity and regulatory frontiers

The green revolution enhanced global food production, ensuring food security for a rapidly growing population. However, overreliance on traditional fertilizers has led to environmental degradation and poor nutrient use efficiency. This necessitates a paradigm shift toward sustainable agriculture. Nanofertilizers are a frontier technology having the potential to overcome such challenges by optimizing nutrient delivery and reducing environmental footprint. This review critically assesses the mechanistic basis of nanofertilizers, beginning with synthesis methods and formulation techniques which enable their controlled and targeted nutrient release. It further discusses, the fate and transformation of nanofertilizers in soil and atmospheric matrices. Also, interaction with microbial populations, along with mechanisms of uptake, translocation, and cellular internalization in plants. The review also explores pivotal areas of nanotoxicology, detailing phytotoxicity mechanisms, defining dose-limiting toxicity thresholds, and deliberation on mitigation options. A brief overview of the developing regulatory schemes is also presented, coupled with the present landscape of innovation and future prospects. Such an integration emphasizes the significance of multidisciplinary approach, linking strong regulatory controls with technological development to safely and efficiently harness nanofertilizers for a sustainable and climate-resilient food future.