International biomonitoring assessment values

Hazardous substances in the workplace can be absorbed through the air, skin, or mouth. Therefore, compliance with air limit values can only cover part of the risks in the workplace. Biomonitoring, on the other hand, can integrate all uptake pathways and allows many substances to be directly detected in blood or urine measurements. This is done with two approaches:

1. With exposure biomonitoring, the concentration of substances or metabolites can be measured.
2. With effect biomonitoring, effects of substances and mixtures are measured.

For biomonitoring, there are biological assessment standards in several countries that are also intended to protect the health of workers or from occupational diseases and can provide information on whether workplace protection measures are sufficiently protective. In cooperation with the OECD Working Party on Exposure Assessment, an overview of sources for international assessment values was created, available at: 

Biomonitoring Assessment Values Databases (PDF, 83 kB, 28.10.2024)

As part of its OECD activities, SECO coordinated work on biomonitoring: This resulted in recommendations for a harmonized derivation of health-related biomonitoring assessment standards as well as limit and guideline values (Occupational Biomonitoring Level, OBL). This guidance aims to generate a comparable health protection level for workers in the future.

Additionally, harmonized derivation and application recommendations for health-related biomonitoring assessment standards have been published:

• A Harmonized Occupational Biomonitoring Approach
• A Harmonized Methodology for Deriving Occupational Biomonitoring Levels 
  

In addition, a concept for deriving limit values for biomonitoring of effects was developed in collaboration with Unisanté, SCAHT, OFEV and SUVA, among others, and published in 2025:

• Guiding principles for mixture threshold derivation from effect biomarkers
  

• Guiding principles to advance occupational mixture risk assessment with effect biomarkers
  

The concept and the mixture limit values are intended to provide additional protection for workers who are particularly exposed to complex genotoxic, neurotoxic or reprotoxic mixtures.

Last modification 28.10.2025