Vanadium [V, 23]
347
formed in soils: 400 mg/kg in Fe-rich and 440 mg/kg in Mn-rich nodules. There
is a competition between V and P for the same retention sites on surfaces of soil
particles, which resulted in low adsorption of V at a high P content. Vanadium
may replace Mo and Fe in nitrogenase, which play an important function in the N
fixation by Azotobacter.
There are not many reports on V contamination of soils, but it is most likely that
some industrial processing (ore smelters, cement and P-rock plants), as well as burning of coal and oil, increase its deposition on soils. Especially serious sources are
combustion of fuel oils and deposition of fly ash. The highest V contaminations are
reported for soils polluted by fly ash (up to 429 mg/kg) and for soils near a graphite
industry (up to 840 mg/kg) (Kabata-Pendias 2011).
53.3 WATERS
The average concentration of V in seawaters is estimated to be 2.5 μg/L, within
the range of 1–3 μg/L. Waters of the North Pacific contain V at an average value
of 2 μg/L (Nozaki 2005). However, its higher concentration, up to 30 μg/L, is also
reported (ATSDR 2012d).
Vanadium concentrations in river waters range from 0.02 to 5.8 μg/L, at the world
mean of 0.71 μg/L (Gaillardet et al. 2003). Waters of the Nordic lakes from some
countries contain V as follows (mean values, μg/L): Finland, 3.1; Norway, 2.2; and
Sweden, 2.5 (Skjelkvale et al. 2001).
Municipal waters of the United States contain V within the range of 1–6 μg/L,
whereas in waters of some U ore region its content is elevated up to 70 μg/L (ATSDR
2012d). Waters of rivers from some industrial regions of Poland contain V from 4 to
19 μg/L (Kabata-Pendias and Pendias 1999).
The highest V concentrations in surface waters, up to about 200 μg/L, were recorded
in the vicinity of metallurgical plants or downstream of large cities (WHO 1988). Its
anthropogenic sources account for only a small percentage of the dissolved V, reaching
the oceans (IARC 2006).
_
Vanadium in waters occurs in several species, such as VO , V O , VO
2
5
2+
, and H VO 4 .
2
2
However, V is not very mobile in aquatic environments and is rapidly fixed in bottom sediments. Thus, V contents of sediments can be an indicator for the pollution of
waters. Sediments of some Baltic Sea coast regions contain V from 53 to 153 mg/kg
(Szefer 2002).
Both zoo- and phytoplanktons accumulate V, and its content may reach 80 mg/kg
(Szefer 2002). It stimulates photosynthesis in algae. Several species of algae produce V-bromoperoxidase (V-Br-peroxidase) that controls the behavior of Br in
waters. Vanadium is involved, as a component of the enzyme (V-Br-peroxidase),
in the process of reduction of hydrogen peroxide due to the alteration from V 3+
to V 5+ .
The median V concentration in bottled waters of the EU countries is 0.15 μg/L
and is quite similar to its mean level in tap water, estimated to be 0.17 μg/L (Birke
et al. 2010). According to the ATSDR (2012d), the average V concentrations in tap
water are approximately 1 μg/L.