Environmental DNA (eDNA) from humans: Review of recent advancements and forensic implications.

Abstract

The collection and analysis of biological samples for DNA profiling have become indispensable tools in forensic investigations, facilitating both the incrimination and exoneration of individuals implicated in criminal activities. Every individual constantly release traces of their DNA into their surroundings, depositing genetic material in the environment. Recent advancements in DNA technology have enabled the detection and profiling of these trace samples containing minimal cellular material. These evidences expand the scope of forensic analysis to a new concept of environmental DNA (eDNA) which refers to genetic material recovered from environmental matrices such as water, soil, and air. While eDNA has traditionally been utilized in ecological contexts-such as non-invasive species monitoring and population genetics-its forensic applications are now garnering significant attention. Between 2005 and 14th February, 2026 different keyword searches in Google Scholar, Scopus and PubMed revealed that about 25% of eDNA studies focused on biodiversity, 27% on conservation, and only 10% on forensic applications-with a mere 0.08% dedicated to human eDNA. This review, therefore, concentrates on human eDNA analysis from environmental sources such as water, air, and soil, along with their downstream applications. The approach offers a promising, non-invasive avenue for collecting biological evidence, potentially transforming forensic investigation methods. At the same time where eDNA research grows, it must also address key legal and ethical issues such as consent, data ownership, and privacy. This review summarizes recent advances and future directions in forensic eDNA, emphasizing the need for strong ethical and regulatory frameworks for its responsible use.