Derivation of an inhalation TTC for the workplace based on DNEL values reported under REACH

Within the scope of the European REACH legislation, several thousand systemic long-term inhalation Derived No Effect Levels (DNELs) for workers have been published. By statistical evaluation of the DNEL distribution of 1876 chemicals and the resulting 99th percentiles, we propose an inhalation workplace TTC for systemic effects in the region of 50 μg/m3 (7 μg/kg body weight/day). Specific exclusion criteria apply for the discussed concept.