Laboratory Diagnosis of Poisoning: Current Concepts, Analytical Advances and Emerging Perspectives

Abstract

Laboratory investigation is central to the diagnosis and interpretation of poisoning in both clinical and forensic practice. This review summarises current principles of specimen selection, post-mortem sampling, biochemical assessment, and analytical methodology, and then examines emerging approaches that may reshape toxicological diagnosis. Blood, urine, gastric contents, hair, nails, vitreous humour, and post-mortem tissues each provide different information and have distinct limitations. Interpretation is influenced by toxicokinetics, sampling time, specimen integrity, post-mortem redistribution, and the distinction between screening and confirmatory testing. Conventional approaches including colorimetric tests, immunoassays, chromatography, and mass spectrometry remain essential, while HRMS increasingly permits suspect and non-targeted screening. Metabolomics, proteomics, microRNA-based markers, pharmacogenetic approaches, and AI-assisted analysis offer additional avenues for detecting exposure and biological effect. However, most emerging technologies remain complementary rather than replacements for validated toxicological methods. Future progress will depend on analytical standardisation, quality assurance, appropriate reference databases, multidisciplinary interpretation, and equitable access to advanced laboratory facilities.