The Dangers of Heavy Metals (Pb, Cd, Hg, Ni, Cu) in Water, Soil, and Food and the Importance of Chemical Analysis for Early Detection

Heavy metal contamination, particularly lead (Pb), cadmium (Cd), mercury (Hg), nickel (Ni), and copper (Cu), has become a global concern due to its persistence, bioaccumulation, and toxicity. Contamination in water, soil, and food threatens environmental sustainability, food security, and public health. This literature review aims to analyze the dangers of heavy metals across environmental compartments and highlight the importance of chemical analysis for early detection. The study employs a qualitative literature review method, systematically examining peer-reviewed articles, conference papers, and reports published between 2021 and 2025. The population consists of recent international studies, while purposive sampling was used to select relevant works focusing on contamination and detection technologies. The main instrument is the researcher, supported by structured data extraction, while data analysis uses content and thematic analysis following reduction, display, and conclusion stages. Findings indicate widespread contamination of croplands and water systems, with clear evidence of heavy metals entering the food chain and posing health risks such as neurological, renal, and developmental disorders. Conventional laboratory methods like AAS and ICP-MS are effective but limited for field monitoring, while innovative tools such as microfluidic and electrochemical sensors show promise for real-time, portable detection. In conclusion, heavy metal pollution is systemic, requiring integrated monitoring and multi-compartmental approaches. Novel detection technologies, if validated and implemented, can strengthen early warning systems and preventive actions for safeguarding ecosystems and human health.