Environmental exposure to cadmium and factors affecting trace-element metabolism and metal toxicity

Abstract

In the general population, food constitutes the major environmental source of cadmium (Cd) in nonsmokers. It is established that leafy vegetables, roots, and grains (wheat or rice) can accumulate relatively high amounts of Cd from the soil. Beef liver and kidney and shellfish are also major dietary sources of Cd. The daily intake of Cd in various parts of the world is different and depends on both the dietary habits and concentration of Cd in foodstuffs. Because of the long biological half-life of Cd in humans and absence of any specific indicators of its toxicity, the environmental exposure of Cd should be monitored in various countries. Although environmental Cd poisoning is rare, there are isolated reports on excessive exposure to Cd in Japan and Shipham, a zinc-mining town in England. The body retention and toxicity of Cd depends on various factors, such as daily intake, the form of Cd in food, its interactions with essential elements, and nutritional status of the population. Since kidney is considered a critical organ in Cd toxicity, the indicators of renal dysfunction have been widely used for evaluation of Cd poisoning in occupationally exposed people. It is unclear whether similar indicators can be used for monitoring environmental Cd exposure.

Cadmium distribution and toxicity in tissues of small rodents

“…The cadmium-zinc, cadmiumcopper, and cadmium-iron interactions are strictly connected and are dependent on the dose of those elements (Church and Pond, 1974;Kabata-Pendias andPendias, 1993, Peraza et al, 1998). The first interactions take place in the gastrointestinal tract during absorption (Chmielnicka and Cherian, 1986;Groten and van Bladern, 1994).…”

Sensorimotor developmental delays and lower anxiety in rats prenatally exposed to cadmium

“…In addition, Cd is generally found in low concentrations in food, air, water and cigarette smoke (Chmielewska and Cherian, 1986;WHO, 1992;Muller and Anke, 1994). Clinical and experimental studies have demonstrated an embryotoxic action of Cd.…”

Interactions between copper and cadmium modify metal organ distribution in mature tilapia, Oreochromis mossambicus

“…As a result, various blood parameters (McKim et al, 1970;Christensen et al, 1972), enzyme activities in blood (Christensen and Tucker, 1976) and reproduction (Homing and Nieheisel, 1979) are affected. In contrast to Cu, a biological function for Cd is unknown, and the metal is toxic to organisms at very low concentrations (Chmielnicka and Cherian, 1986). For example, exposure to Cd resulted in reduced growth, reproduction and survival in flagfish Jordanella floridae (Spehar, 1976).…”