Heavy metals and microplastics as emerging contaminants in processed foods: Shared contamination pathways, health risks, advanced detection, and mitigation strategies

Heavy metals (HMs) and microplastics (MPs) are emerging contaminants that can co-occur in processed foods, threatening food safety and human health. Although these contaminants are commonly investigated separately, growing evidence indicates that they frequently originate from shared contamination pathways. Thus, this review aimed to present a pathway-oriented framework integrating HM and MP contamination across processed food production chains, including raw materials, process water, food additives, processing equipment, packaging materials, environmental exposure, and hygiene-related practices. Recent evidence demonstrates the occurrence of these contaminants in diverse processed foods, including cereals, dairy products, meat products, beverages, seafood, and infant foods. This study further synthesizes current advances in chromatographic, spectroscopic, electrochemical, and biosensing technologies, including AI-assisted analytical approaches for detecting contaminants in complex food matrices. Existing toxicological evidence suggests that co-exposure to HMs and MPs may contribute to synergistic health risks. Emerging mitigation strategies involving source control, advanced filtration systems, biological remediation, sustainable packaging technologies, wastewater treatment, and KAP-based interventions are critically evaluated. This review further highlights major regulatory gaps, including the lack of harmonized standards and integrated risk assessment frameworks for combined contaminant exposure, while providing a unified system-level perspective to support integrated monitoring strategies and comprehensive food safety policies for processed foods.