Abstract
Food contaminants-including chemical, biological, physical, allergenic, and radiological agents-pose major global food safety challenges. This review synthesizes evidence from 2014 to 2025 on Food contaminants sources, cellular and molecular mechanisms, monitoring strategies, and mitigation approaches. Major food contaminants include heavy metals (lead, mercury, cadmium, and arsenic), mycotoxins (aflatoxins, and ochratoxin A), pesticide residues, allergens, microplastics, per- and polyfluoroalkyl substances (PFAS), radioactive isotopes (cesium-137, and iodine-131), and microbial agents such as Bacillus, Salmonella, Listeria, and Escherichia species. At the molecular level, heavy metals trigger oxidative stress, mitochondrial dysfunction, and DNA damage; aflatoxins form DNA adducts, driving carcinogenesis; organophosphate residues inhibit cholinesterase; allergens activate IgE-mediated hypersensitivity; and radiological agents generate reactive oxygen species, causing lipid peroxidation and genomic instability. Regulatory agencies, including WHO, FDA, EFSA, and the European Commission, classify metals as priority hazardous substances and set maximum residue limits (MRLs), tolerable daily intakes (TDIs), and action levels for vulnerable populations, such as children. For example, cadmium in wheat is limited to 100 ppb in the EU, lead in candy to 0.1 ppm, and arsenic in apple juice to 10 ppb. Advanced detection technologies, such as liquid chromatography-mass spectrometry (LC-MS) and inductively coupled plasma mass spectrometry (ICP-MS), enable precise monitoring of contaminants at trace levels. Mitigation strategies emphasize improved agricultural practices, safe processing, allergen control, environmental monitoring, and policy enforcement. Ongoing research on emerging contaminants, particularly PFAS and nanoplastics, is crucial to strengthening food safety systems and protecting public health.