Environmental geochemistry of emerging contaminants: impacts on agroecosystem function, food security, and human...

Agroecosystems, which sustain global food production and economic stability, face increasing threats from emerging contaminants such as microplastics, Per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, and engineered nanomaterials (ENMs). These pollutants persist in the environment, bioaccumulate in crops, and impose complex risks to soil health, biodiversity, and human well-being. Microplastics derived from agricultural plastics and sewage sludge disrupt soil structure and microbial communities, while PFAS migrate into groundwater and contaminate drinking water supplies. Pharmaceuticals introduced through wastewater irrigation and manure application accelerate antimicrobial resistance, and ENMs used in agrochemicals influence nutrient dynamics and soil chemistry. Despite growing recognition of these hazards, regulatory responses remain fragmented and current risk-assessment frameworks insufficient. This review synthesizes advanced detection tools-including CRISPR-based biosensors, machine-learning contamination mapping, and high-resolution spectroscopy-with sustainable remediation strategies such as phytoremediation, biochar amendments, and nano-enabled pollutant degradation. By comparing emerging contaminants with conventional pollutants, this work establishes their unique persistence, mobility, and policy challenges while linking their impacts to Sustainable Development Goals (SDGs) 2, 3, and 6. Importantly, the review emphasizes that long-term resilience of agroecosystems requires coordinated global policy alignment, integration of interdisciplinary monitoring systems, and stakeholder engagement to reduce contaminant loads. Future research should prioritize harmonized toxicity thresholds, long-term field experiments on contaminant-crop interactions, and scalable, low-cost detection platforms suitable for resource-limited regions. Together, these efforts will be essential for mitigating EC-related risks, strengthening food security, and safeguarding environmental and public health.