Biological Limit Values

Biological indicators of nickel exposure are currently under study by several non-governmental bodies, including the American Conference of Governmental Industrial Hygienists (ACGIH) and the World Health Organization (WHO).

In 1990, the Maximale Arbeitsplatz- Konzentrationen Commission (MAK) in Germany established “EKAs” (exposure equivalents for carcinogenic materials) for nickel. Despite the generally recognized poor correlation between exposure and nickel concentrations in urine (Bernacki et al., 1978; Høgetveit et al., 1978; Morgan and Rouge, 1979; Raithel et al., 1981; Aitio, 1984; IPCS, 1991), the MAK recommended an EKA of 50 µg Ni/L in urine as being equivalent to an airborne exposure of 0.5 mg Ni/m3. The 0.5 mg Ni/m3 level is the current maximum allowable concentration in Germany for water-insoluble forms of nickel.