Quo vadis human biomonitoring?

The increasing presence of chemicals in commerce and their potential impacts on human and environmental health necessitate innovative approaches in exposure science, biomonitoring, and risk assessment. With over 450,000 synthetic chemicals currently in use and growing concerns about their ecological and human health effects, prioritizing chemicals for environmental risk assessment remains a critical objective. This review examines recent advancements in chemical prioritization, predictive toxicology, genomic databases, and biomonitoring techniques for evaluating health effects associated with chemical exposure. The significant progress achieved in recent years offers new opportunities for more comprehensive analyses of key factors influencing health outcomes.

Currently, fewer than 1000 chemicals have been analyzed in environmental studies, and fewer than 450 chemicals have been assessed in biomonitoring studies. This limited number constrains the ability to fully characterize real-world exposures and their potential health implications. Urinary biomarkers are frequently utilized in biomonitoring research, yet their interpretation remains complex due to the high intra-individual variability of non-persistent chemicals. As a result, single-sample assessments may not always provide an accurate representation of chronic exposure levels, underscoring the importance of refining biomonitoring methodologies to strengthen the reliability of exposure-health associations.

While biomonitoring effectively detects low-level exposures, linking these values to specific health outcomes is complex due to interactions between exposure, genetics, environmental factors, and individual health status. Furthermore, for many chronic diseases, long latency periods complicate direct exposure-disease correlations.