Current recommendations submitted to the Federal Ministry of Labour and Social Affairs in July 2026 / Commission publications included in leading US databases
The DFG’s Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has presented its latest research-based recommendations on the risk assessment of substances used at the workplace and submitted them to the Federal Ministry of Labour and Social Affairs in July 2026.
The Commission’s annually published
List of MAK and BAT Values, which is now available in English, provides recommended occupational exposure limits and serves as a key basis for implementing Germany’s Hazardous Substances Ordinance (GefStoffV). The recommendations put forward by the Senate Commission on the handling of hazardous substances are first assessed by the Federal Ministry of Labour’s Committee on Hazardous Substances, and statutory regulations are subsequently drawn up on this basis as necessary.
MAK Values – Reassessment of Airborne Manganese
The MAK values contained in the list indicate maximum workplace concentrations, i.e. the quantities of a substance that do not cause any long-term harm at the workplace as a gas, vapour or aerosol in the air. In terms of the current recommendations on airborne exposure limits, the Commission changed the risk assessment of ten substances based on new scientific findings. Among other things, it reassessed manganese and its inorganic compounds. This is particularly relevant for employees working in the metalworking industry, because welding generates dusts and fumes that may contain very small manganese particles, for example. Once absorbed through the alveoli of the lungs, these particles can be distributed throughout the body, accumulate in the brain and produce neurotoxic effects.
“For the reassessment, we were able to draw on fifty new studies, including large epidemiological cohort studies from Australia, South Africa and the United States, as well as MRI scans of affected areas of the brain. These were systematically compiled, correlated and evaluated in accordance with our assessment criteria,” explains Professor Dr. Christoph van Thriel, Head of the Commission’s Working Group on Neurotoxicity and Sensory Systems and Professor of Neurotoxicology and Chemosensory Research at the Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund University (IfADo). Drawing on the work of several of its working groups, the Commission concluded that exposure to 0.05 mg of manganese per cubic metre of air is not expected to cause adverse health effects.
Six Changes to BAT Values
The recommendations issued by the Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area also include biological limit values in blood and urine, enabling individual exposure resulting from contact with workplace substances to be assessed from the perspective of occupational medicine and toxicology. This includes the concentrations of a substance in the body that a person can be exposed to throughout their working life without adverse health effects – known as biological work substance tolerance values (“BAT”) – and also the biological reference values (“BAR”), which can be used to assess the extent of occupational exposure. This year’s list includes revisions to the biological tolerance values in blood and urine for six substances, including sevoflurane, inorganic lithium compounds and strontium.
New Substances Added
The Commission has added a total of three substances to the list of recommendations: benzophenone, melamine and p-toluenesulfonic acid. Benzophenone is a chemical compound used as a photoinitiator in the printing industry, in chemical synthesis and as a fragrance ingredient in cosmetic products, for example. Melamine is used in the manufacture of melamine resins, which are employed in plastics and adhesives. The newly established BAT value of 300 µg melamine/l urine now provides a health-based reference value for assessing exposure in individuals who have absorbed melamine. For p-toluenesulfonic acid, a strong acid, the Commission derived a MAK value of 0.2 mg/m³. p-toluenesulfonic acid is used as a catalyst in chemical synthesis, for example, as well as a curing agent and descaling agent.
Increased International Visibility
Over the past year, the Commission published a total of seventy publications, including forty MAK documentation reports, ten BAT documentation reports, ten descriptions of air monitoring methods and ten biomonitoring methods. “The fact that we’ve been able to achieve this volume of publications reflects the exceptional voluntary commitment of all the scientists working together across disciplines within the Commission,” says the Commission Chair, Professor Dr. Andrea Hartwig of the Karlsruhe Institute of Technology.
Since spring this year, new publications issued by the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area have also been indexed in the US National Library of Medicine (NLM) databases PubMed and PubMed Central, thereby further enhancing the international visibility of the Commission’s work. “Inclusion in PubMed and PubMed Central reflects both the quality and the relevance of the Commission’s work for evidence-based occupational health and safety worldwide,” says Hartwig.
Detailed scientific justifications are available for each of the substances reviewed. In order to ensure the recommendations are up to date with the latest scientific findings, the proposed amendments and new additions remain open for discussion until 31 December 2026. New data or scientific comments can be submitted to the Commission up until that date.All substance documentation reports and method descriptions prepared by the Senate Commission are available in the
MAK Collection. In addition to the Commission’s latest scientific findings, all other publications are available on an open-access basis, ensuring that the knowledge generated can be widely reused for scientific purposes.