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Trace Elements in Abiotic and Biotic Environments
stream waters may be elevated up to the range of 14–98  μg/L (Reimann and de
Caritat 1998).
Maximum Y contents of snow from the Kola Peninsula range from 0.01 in
remote regions to 0.7 μg/L in polluted regions (Reimann and de Caritat 1998). Its
concentrations in rainwater, collected in Sweden during 1998, varied from 0.003 to
0.033 μg/L, at an average value of 0.01 (Eriksson 2001a).
Yttrium is adsorbed by bottom sediments, in relatively high amounts, with the
maximum values of 485, 731, and 2005 mg/kg in Germany, Scotland, and Austria,
respectively (Reimann and de Caritat 1998). The top layers of bottom sediments of
Swedish rivers, at the Baltic catchments, contain Y within the range of 13–23 mg/kg
(Szefer 2002).
The median Y concentration in bottled waters of the EU countries is 0.014 μg/L
and is similar to its mean level in tap waters, estimated to be 0.01 μg/L (Birke et al.
2010). Drinking waters contain Y usually within the range of 1–30 μg/L, with the
mean value of 5 μg/L.
54.4 AIR
Atmospheric dust contains Y within the range of 0.2–2 mg/kg. Its maximum concentration, of 6.0 ng/m 3 , is reported for air of industrial areas (Reimann and de Caritat 1998).
Mosses collected in Sweden, during the period 1990–1995, contained fairly similar amounts of Y from 0.04 to 2.3 mg/kg, which clearly indicates a small variation
in its concentrations in air at that time (Berg and Steinnes 1997). Similar Y contents
(up to 2.0 mg/kg) are reported for mosses collected earlier (1970) in Norway (Erämetsä
and Viinanen vide Kabata-Pendias 2011). Increased Y levels in mosses and lichens,
compared with higher plants, clearly indicate that its main sources are atmospheric
deposition. Yttrium wet deposition in Sweden has been estimated to be 1  g/ha/yr
(Eriksson 2001a).
Yttrium contents of moss (Hylocomium splendens) from the mountains in Poland,
0.11–0.18 mg/kg (mean 0.14 mg/kg), are slightly lower than those of the same moss
species from Alaska, 0.06–0.73 mg/kg (mean 0.23 mg/kg). This may suggest relatively similar Y atmospheric deposits in both regions (Migaszewski et al. 2009).
54.5 PLANTS
Yttrium contents of higher plants vary considerably, mainly from 0.01 to 3.5  mg/kg,
depending on soil and climatic factors. The reference Y contents of plants are proposed as 0.02 mg/kg (Markert and Lieth 1987). However, vegetables may contain
Y within the range of 20–100 mg/kg, depending on plants and growth media. Its
contents of cereal grains vary from 0.8 to 1.3 mg/kg (Eriksson 2001a).
54.6 HUMANS
Yttrium content in the human body is estimated to be 0.5 mg (Emsley 2011). It may
bind weakly to various organic ligands and may compete for the binding sites of
some other elements. It is toxic in excess amounts.