Food sources cadmium

Roy, I. and Hare, L. (1999). Relative importance of water and food as cadmium sources to the predatory insect Sialis velata (Magaloptera), Can. J. Fish. Aquat. Sci., 56, 1143-1149. 

Cadmium TT a simple microcosm experiment associating two biotic levels conducted in a Petri dish allows measurement of reproduction effects on daphnids following Cd contamination of either their food source (algae) or of their water medium. I (Janati-Idrissi et ah, 2001)... 

Williams, D.R. and J.P. Giesy, Jr. 1978. Relative importance of food and water sources to cadmium uptake by Gambusia affinis (Poeciliidae). Environ. Res. 16 326-332. 

Food is the main source of cadmium input to human organisms, however the smokers take in a much larger amount of this element with tobacco smoke. The average period of cadmium storage in the human body is 18 years. 

On the basis of chemical profile, Wood (38) predicted that arsenic, selenium, and tellurium will be methylated in the environment, and lead, cadmium, and zinc will not. Elemental concentration in the aquatic food chain has been reported for As (39), Hg (40), Cd (41), Pb (42), and Cu (43). The biological half-life of methylmercury in fish, for example, is one to two years (44). Pillay et al. (40) implicated heavy coal burning in the mercurial contamination of plankton and fish populations of Lake Erie. Other metals, notably cadmium, have been shown to be incorporated into the grazing grasses surrounding a coal burning source (27). Trace element contamination, therefore, can enter the food chain at various points. Disposal of solid wastes in the form of ash and slag is yet another environmental consideration (45). 

The presence of elements known to have adverse health effects in humans such as lead and arsenic is obviously undesirable in food. Environmental sources are the main contributors to contamination of food with most metals and other elements. Some elements (e.g. arsenic) are present naturally but the major sources of other elements (e.g. lead) in the environment are from pollution from industrial and other human activities. The presence of metals and other elements in food can also be the result of contamination from certain agricultural practices (e.g. cadmium from phosphate fertilisers) or manufacturing processes (e.g. tin in canned foods). 

For mean and 97.5th percentile adult consumers, the dietary exposures from the 1997 UK TDS were 0.014 mg/day and 0.024 mg/day respectively. These exposures to cadmium from food and other sources (e.g. air, water and smoking)... 

The impact to health has been mostly dependent on the concentration of the candidate metal. Some metals (e.g., mercury, lead, arsenic, cadmium, iron, copper) ultimately find their way into human systems via soil, minerals, and water. Studies have shown the presence of many metals in daily consumable products (e.g., food, fruits, milk, fabric materials, drinking water). Further, heavy metals associated with particle material can be accumulated in areas suitable for sedimentation or particle concentration (e.g., upstream from sills or dams, in estuary sludge clog, etc.). These accumulation areas are creating possible pollution sources, as particles pooled could be resuspended during punctual hydrologic periods (floods, drains). Bioavailability, and therefore toxicity of heavy metals, is strongly bound to the current chemical form. 

Heavy Metals Limits (Policy) The Committee on Food Chemicals Codex notes the importance of providing limits for individual heavy metals as required by the source and composition of individual food additives. Thus, it has decided to remove from most monographs the general heavy metals (as lead) limits and tests and, based on the current level and availability of scientific information and on the policy stated below, to replace them with limits and tests for specific heavy metals such as lead, cadmium, and mercury as may be relevant to each substance. 

From local sources poisonous elements have been spread through the atmosphere to the soil. Close to a zinc factory in Odda, western Norway, great concentrations of heavy metals in the soil and plants have been proved. The content of cadmium for example, is so high that warnings have been issued against substantial dependence upon food plants grown in the vicinity of the factory (Lag, 1975). 

Food and cigarette smoke are the most likely sources of cadmium exposure for the general population. The total daily intake of cadmium from food, water, and air for an adult fiving in North America or Europe is estimated to be between 10 and 40 micrograms (3.53 X 10 and 1.41 X lO ounces). The U.S. Environmental Protection Agency has established oral reference doses for cadmium 0.0005 mg/kg/day (from water) and... 

Chronic Environmental Exposure Itai-itai disease (for details, see Part III, Chapter 6) was first reported in 1955 among the human population of Toyoma, Japan. Urinary cadmium levels were found to be high in affected patients. Studies showed that cadmium content was particularly high in rice, a staple food for this population. The source of cadmium was felt to be via water from the Kamiaha mine upstream from Toyama. It was concluded that cadmium played the most important role in the development of Itai-itai disease (Friberg et al. 1979). 

In addition, periodic review articles are published in the Analyst and Pure and Applied Chemistry, as well as in other sources, oriented either to technique, analyte or material. Examples are Robards and Wors-fold (1991) Cadmium toxicology and analysis, A review. Analyst (London) Schuller and Egan (1976) (a review of methods of trace analysis and sampling with special reference to food for the determination of cadmium, lead, mercury and methylmercury (MeHg) compounds, FAO publication) and... 

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