Cadmium daily intake levels

Cadmium daily intake levels in most OECD nations have been decreasing steadily since the 1970s and today range from 10 to 20 jig per day, well below any levels of human health concern (International Cadmium Association 1999). These relationships are shown in Figure 6. 

Selenium is readily available in a variety of foods including shrimp, meat, dairy products, and grains, with a recommended daily intake of 55 to 70 jug. It occurs in several forms with Se+6 being biologically most important. Selenium is readily absorbed by the intestine and is widely distributed throughout the tissues of the body, with the highest levels in the liver and kidney. It is active in a variety of cellular functions and interacts with vitamin E. Selenium appears to reduce the toxic effects of metals such as cadmium and mercury and to have anticarcinogenic activity. Selenium produces notable adverse effects both in deficiency and excess thus recommended daily intake for adults is approximately 70 Jg/day but should not exceed 200 pg/day. 

Figure 6. Daily Cadmium Intake Levels for General Population...

Human exposure to high concentrations of cadmium are rare and current concern centers around the chronic toxicity caused by long-term exposure to low levels of the metal. Bone disorders are one manifestation of chronic cadmium exposure. Cadmium is present in all tissues of adults, with the most significant amounts found in the liver and kidney, and the concentrations tend to increase with age. The WHO regards a tolerable daily intake of cadmium to be 70pgd for an adult of 70 kg. 

Phosphorus fertilizers may contain impurities among those are some heavy metals that are of concern. In particular, cadmium (Cd) has received attention during the past few years. The level of cadmium content in fertilizers has been more or less arbitrarily limited to the concentration of 50 mg Cd/kg of P2O5 [7]. WHO has limited the daily intake of Cd to 1 microgram Ag of body weight per day [7]. The current average intake in Europe is lower than this limit [8]. 

Human beings are exposed to cadmium in food, water, and air. Of these routes of exposure, food is considered to be the major one. In contaminated areas, cadmium is accumulated in certain kinds of food, especially liver and kidney from animals and shellfish High concentrations may also be found in oysters and crabs. Rice and wheat in exposed areas may contain high levels of cadmium The daily intake of cadmium from food in uncontaminated areas has been estimated at 25-60 xg for a 70 kg person. ... 

Recommendations for cadmium in air and human health protection under the worst scenario (Table 1.8) assume that total daily air intake is 27.14 m3 for an adult human who spends about 6.3 h in occupational exposure to air containing 100 pg Cd/m3 (USEPA 1980). Under these conditions, a 70-kg adult would retain about 361 pg Cd/day, based on an absorption factor of 0.5 (USEPA 1980), and most of this cadmium would probably be translocated to the kidney a critical threshold level of 200 mg Cd/kg in the kidney would be reached in about 1.52 years. It is not now known... 

Monitoring human food and the evaluation of daily dietary intake of toxic metals is a part of international efforts to assess the integral human exposure to various pollutants. The greatest attention is presently paid to lead, cadmium and mercury. They are released continuously into the environment, and tho efore, reflect increasing levels in human food. 

This review will be focused on available literature data of concentration levels of lead, cadmium, and mercury in different food items in Croatia and in other republics of former Yugoslavia, compared to other eastern and western European countries. The evaluation of the daily dietary intake of metals in general population, obtained by different methods will be also presented compared to other countries. Although the author is aware of the high risk groups within the country population (small children and pregnant women), the data presented here q)ply only to adult general population, as such data from other countries are available in the literature. 

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