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Trace Elements in Abiotic and Biotic Environments
Ni were 0.082 mg in Sweden and 0.16 mg in Denmark in 1987. The dietary intake
of Ni in a Canadian study ranged from 0.19 mg/day for 1- to 4-year-old children to
0.406 mg/day for 20- to 39-year-old males; the Ni intake for 20- to 39-year-old women
was, on average, 0.275 mg/day (WHO 2005a). The population dietary exposure to Ni
in the United Kingdom was estimated to be 0.13 mg/day in 2006, and this is the same
as previously reported in 1997 and 2000 (Rose et al. 2010).
29.7 ANIMALS
Nickel is an essential element in a number of laboratory animal species, although its
functional importance has not been clearly demonstrated. It is considered essential,
based on the reported Ni deficiency in several animal species (e.g., rats, chicks, cows,
goats). Nickel deficiency is manifested primarily in the liver functions, including
abnormal cellular morphology, oxidative metabolism, and increases and decreases
in lipid levels. In animals, Ni deficiency is associated with disturbances and reduced
growth, impaired reproductive function, and reduced hematopoiesis.