AbstractCadmium is a toxic heavy metal which have a destructive impact on most organ systems.
It is widely distributed in humans, the chief sources of contamination is cigarette smoke and contaminated food and drinks. It’s toxict effect increases as its amount increases in the body. EDTA and other chelators are used in the detoxification of cadmium. INTRODUCTION Cadmium (Cd) is a naturally occuring toxic heavy metal. It is a silvery white metal having atomic number 48.It is situated in the periodic table of elements between zinc and mercury. It exists as a divalent cation, complexed with other elements eg CdCl2.
It is found in earth’s crust associated with zinc,lead and copper ores. Cadmium is used in television screens, lasers, batteries, paint pigments, stabilizers for plastic and in electroplating. It’s common exposure is in industrial workplaces, plant soils, and from smoking and contaiminated food. It is extremely toxic in low concentration and accumulates in organisms and in ecosystem.SOURCESFood Source Most common foods such as rice and wheat which are grown in contaiminated soil by super phosphate fertilizers and irrigation water are the good source of cadmium toxicity. Some other food sources are organ meats such as liver and kidney.
Large ocean Fish like Tuna, Oysters, Codfish and Haddock contain large ammount of cadmium within their tissuesCanned food Sealing cans are the good source of cadmium.Drinking Water New plastic pipes made up of PVC which are used in the supply of drinking water are the good source of cadmium.Electroplating, Batteries and Semiconductors Workers in these industries are at risk of exposure. Cigarette Smoke Cigarettes are especially dangerous because cadmium is efficiently absorbed when inhaled. Burning of Rubber Goods, Tires, Plastics and Paints Cadmium levels are highest in those areas where burning of plastics and tires takes place and where vehicle exhaust levels are higher.
Metabolism Of CadmiumAbsorptionAbsorption of cadmium is highest through inhalation. Cadmium toxicity is more common in women as compared to men.Dietary absorption of cadmium is due to the deficiency of calcium, zinc, copper, iron and protein in the diet.RetentionIngested, or inhaled cadmium is stored in the liver and kidneys.
High concentrations of cadmium are also deposited in the pancreas and salivary glands. Other storage sites may also include the joints, arteries, or in the bones. ExcretionExcretion of cadmium occurs through the kidneys and liver, but the excretion rate is normally very low.
The biological half-life of cadmium is probably between 10 and 30 years.Effects On Other Mineral ZincCadmium can replace zinc in many metallo-enzyme binding sites. Sodium Cadmium causes sodium retention by damaging the renal tubules which can contribute to a hypertension.
Copper Cadmium reduces copper levels in the liver because copper is not adequately bound, it becomes biounavailable.ManganeseHepatic and renal manganese are increased by cadmium.