Derived No-Effect Level (DNEL)

Abstract

The Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) derived no-effect level (DNEL) is defined by the European Chemicals Agency (ECHA) as “… the level of exposure above which humans should not be exposed.” DNELs are derived for substances (i.e., chemicals and mixtures) that exhibit a threshold dose–response relationship. Based on the available, relevant health hazard data, substance-specific DNELs can be derived for both the worker and general populations (including consumers). The starting point for DNEL derivation is usually a no observed adverse effect level (NOAEL), lowest observed adverse effect level (LOAEL), or benchmark dose (BMD) from experimental animal studies. ECHA has developed extensive guidance on the DNEL derivation process. DNELs are used in REACH risk characterization process for REACH-regulated substances.