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most severe example of chronic Cd poisoning caused by prolonged oral Cd ingestion. For the first time, Cd
pollution was shown to have severe consequences on human health, particularly in women. The most important
effects were softening of the bones and kidney failure. The name of the disease is derived from the painful screams
(Japanese: itai) caused by the severe pain in the joints and the spine of the victims. Its cause was found to be
due to environmental Cd pollution originating from effluent from a zinc mine located in the upper reaches of the
river (
Figure 23.1
)
. In the Cd-polluted areas, 50%
70% of the amount of Cd ingested orally was derived from
e
FIGURE 23.1
Itai
e
Itai disease. (left) the degree of Cd pollution and (right) the presence of the disease in women over 50 years of age.
rice, and in practice a close association was reported between the prevalence of Itai
Itai disease and the Cd
e
concentration in rice.
Although Cd emissions in the air have been constantly decreasing since the 1960s due to improved technology
for the production, use, and disposal of Cd and Cd-containing products, industrial Cd consumption in the world
has increased steadily (from 18,400 tons in 2003 to 20,400 tons in 2007). Occupational and environmental
pollution with cadmium can result from heavy metal mining, metallurgy and industrial use, manufacturing of
nickel
cadmium batteries, pigments, plastic stabilizers, and anti-corrosive products. Important sources of human
intoxication are cigarette smoke, due to high concentrations of cadmium in cigarettes (smokers on a packet a day
can easily double their cadmium intake), as well as food, water, and air contamination. In Europe, the highest Cd
levels in soil were found to occur in topsoil and to follow closely the distribution of P
2
O
5
, suggesting that the
contamination is derived from the use of rock phosphate fertilizer in intensive arable agriculture.
e
