Derived No-Effect Levels (DNELs) for chemicals registered under REACH

Project No. IFA 1117


completed 12/2013


According to Annex I of EU Regulation No 1907/2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), the objectives of the human health hazard assessment are to derive levels of exposure to the substance "above which humans should not be exposed". This exposure limit is known as the derived no-effect level (DNEL).

DNEL values must be formulated by the manufacturers or importers of dangerous substances subject to registration, and stated in the chemical safety report and on the safety data sheet, when the quantity produced or imported exceeds ten tons per annum. Different DNEL values may be determined for one and the same substance for different groups of persons (e.g. consumers, commercial users, pregnant women, children) and for different durations of exposure and exposure routes.

In Germany, occupational exposure limits (OELs) continue to constitute workplace atmospheric limit values that are binding for employers. Should neither an OEL nor a maximum workplace concentration (MAK) value formulated by the DFG (German Research Foundation) be available, the substance-specific DNEL ("inhalative, long-term, workers") in accordance with the TRGS 402 technical rules for dangerous substances serves as a basis for assessment of whether the measures taken are sufficient.

The DNEL values formulated to date can be found in a sub-chapter of the relevant substance-specific registration dossier on the website of the European Chemicals Agency (ECHA). A comprehensive compilation that would facilitate risk assessment, consulting with the accident insurance institutions and systematic evaluation does not exist at this stage.

Compilation of existing DNEL values in a clear form would facilitate the assessment of exposure in plants.


The DNEL values ("inhalative, long-term, workers") were taken from the individual registration dossiers (approximately 7,000 in number) and placed on the Internet in the form of a list with a user-friendly user interface. A preface to the list describes the criteria by which they were derived, and their legal significance. The list is to be updated regularly.

The project was supported by a consortium comprising several German Social Accident Insurance Institutions (BG BAU, BG ETEM, BGHM, BG RCI, VBG, UK NRW), the Federal Institute for Occupational Safety and Health (BAuA), the Association of the German Chemical Industry (VCI) and the Austrian Workers' Compensation Board (AUVA).


The substances marketed in large quantities which were reported to the European Chemicals Agency by the manufacturers and importers during the first REACH registration period have been included in the DGUV's DNEL list and made available on an IFA Internet portal together with explanatory texts. In order to make it even more user-friendly, the list was embedded in a database which provides guidance on identifying the substances, and on their physical and chemical properties. Substances with a binding German occupational exposure limit and carcinogens are specifically identified.

Initial systematic inspection of the DNEL list revealed a number of contradictions and deficiencies. These included DNEL values for carcinogenic substances with no known toxicological threshold of action, a substantial number of identical DNEL values for different health impacts caused by a substance, and substances in widespread use for which no DNEL entry exists. The results were published in order to facilitate discussion with the European Chemicals Agency and the manufacturers for the purpose of optimising the welcome instrument of "DNEL" for exposure assessment at workplace.

Last Update:

16 Apr 2014


Financed by:
  • Deutsche Gesetzliche Unfallversicherung e. V. (DGUV)
Research institution(s):
  • Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA)
  • UV-übergreifend

-cross sectoral-

Type of hazard:

dangerous substances


limit value

Description, key words:

DNEL, risk assessment, REACH Regulation, chemical agents without occupational exposure limit value (OEL)


Further information