Implementation Reliability in Forensic DNA Contamination Prevention: A Human-Factor Quality-Systems Mini Review

Abstract

DNA contamination remains a persistent challenge in forensic genetics, particularly as sensitive workflows increasingly support the recovery and interpretation of low-level, trace, mixed, or contact-derived DNA. Laboratory contamination-control systems commonly emphasize technical safeguards, including PPE, workflow separation, cleaning, environmental monitoring, negative controls, staff elimination databases, and chain-of-custody documentation. However, these safeguards depend on consistent human implementation under routine operational conditions. This mini review examines how forensic laboratories can integrate human-factor thinking into DNA contamination-prevention quality systems. The review focuses on workload, fatigue, time pressure, training, communication, PPE behaviour, documentation, workspace organization, near-miss reporting, and quality culture as variables that may influence procedural reliability. A practical quality-system approach is proposed in which laboratories identify high-risk workflows, define human-factor indicators, monitor practice through audits and environmental controls, investigate nonconformities and near-misses, implement corrective actions, and review trends at management level. This approach shifts contamination prevention from a reactive response to detected failures toward a proactive quality-management process. Human-factor integration is also relevant to forensic interpretation, because unexpected, mixed, or activity-level DNA findings require evaluation of how DNA may have been introduced, transferred, or contaminated. Future work should validate measurable human-factor indicators and assess their relationship with contamination events, environmental monitoring outcomes, staff matches, and quality-system trends.