Ultratrace elements deficiencies

The ultratrace element requirements of animals (and men) are, in part, extremely low and are reliably met everywhere. In practice, symptoms of ultratrace element deficiency in animals and man do not occur, apart from genetic defects which prevent utilization of the ultratrace elements. Hints as to the biological essentiality of these elements were only obtained in experiments with semisynthetic rations that where extremely poor in the element(s) to be tested. These conditions led to depressed performances, deficiency diseases, and reduced life expectancy. Deficiency symptoms of ultratrace elements were not registered in real life, as the... 

Anke M, Groppel B, Arnhold W, Langer M and Krause U (1990) The influence of the ultratrace element deficiency (Mo, Ni, As, Cd, V) on growth, reproduction performance and life expectancy. In Tomita H, ed. Trace Elements in Clinical Medicine, pp. 361-376. Springer-Verlag Tokyo, Japan. 

Essential ultratrace element in red algae, chick, rat, pig, goat, and probably humans. Deficiency results in depressed growth and increased mortality. 

The most significant differences are found for all major elements (e.g., Ca, K, Mg, Na, and P). However, the ratio Ca P, which is related to structural functions extremely important for the correct development of the newborn, is higher in human milk. Despite their low levels in milk, minor and trace elements play a central role in the organism, since their deficiency or excess may generate undesirable effects in the newborn. This fact and the centrality of milk in the human diet explain the growing interest in the determination of trace elements in milk [6-8], Table 13.6 summarizes the concentration levels for major, trace and ultratrace elements in human and cow milk. 

Arsenic Essential ultratrace element in red algae, chick, rat, pig, goat, and probably bumans. Deficiency results in depressed growth and increased mortality. Moderately toxic to plants, highly toxic to mammals. Serious pollution problems in some areas sources include mining, burning coal, impure sulfuric add, insecticides, and herbicides. 

First, it is interesting to note that a deficiency or excess of one element does not directly induce a particular symptom in cultivated or wild plants. In this respect, it is necessary to examine the macro, trace and ultratrace element transfer from the different polluted and unpolluted soils into the plant. Indicator plants must be easy to identify, grown worldwide, and indicate the mineral transfer to the food chain. On cultivated soils in many parts of the world, these conditions are met by wheat Triticum sativum), rye Secale cereale), and red clover Trifolium pratense sativum) of the field and meadow varieties (TrifoUum pratense spontaneum). The green plants were harvested when the rye was in blossom, the wheat shooting, the field red clover in bud, and the meadow red clover in blossom. 

Reduced growth rate and disturbances in lipid metabolism were observed in piglets separated from their mother immediately after birth and fed a synthetic lead-poor diet (Kirchgessner et al. 1991, Plass et al. 1991). Lead deficiency in rats and pigs can be prevented or abolished by lead supplementation (Reichlmayr-Lais and Kirchgessner 1997). The practical problem of lead is not a deficiency of this ultratrace element, but rather its toxicology (Griin etal. 1982). 

Factors which are important for the lowering of human health risks due to mineral deficiency and intoxication are the normative requirements of the macro, trace and ultratrace elements, recommendations for their intake, their apparent absorption and excretion rates, their interactions, tolerance limits for chemicals in food and water, and occupational health standards. 

The quality of the experimental evidence for nutritional essentiality varies widely for the ultratrace elements. The evidence for the essentiality of three elements, iodine, molybdenum and selenium, is substantial and noncontroversial specific biochemical functions have been defined for these elements. The nutritional importance of iodine and selenium are such that they have separate entries in this encyclopedia. Molybdenum, however, is given very little nutritional attention, apparently because a deficiency of this element has not been unequivocally identified in humans other than individuals nourished by total parenteral nutrition or with genetic defects causing disturbances in metabolic pathways involving this element. Specific biochemical functions have not been defined for the other 15 ultratrace elements listed above. Thus, their essentiality is based on circumstantial evidence, which most often is that a dietary deprivation in an animal model results in a suboptimal biological function that is preventable or reversible by an intake of physiological amounts of the element in question. Often the circumstantial evidence includes an identified essential function in a lower form of life, and biochemical actions consistent with a biological role or beneficial action in humans. The circumstantial evidence for essentiality is substantial for arsenic, boron, chromium, nickel, silicon, and vanadium. The evidence for essentiality for the... 

As already mentioned, the ultra trace elements other than selenium and iodine are a disparate group in terms of their possible requirement or nutritional importance for human health and well-being. Although molybdenum has known essential functions, it has no unequivocally identified practical nutritional importance. The other 14 ultratrace elements discussed here have been suggested to be essential based on circumstantial evidence. This evidence is presented below along with some indication of possible requirement (extrapolated from the deficient animal intakes shown in Table 3), and some indication as to what constitutes a high intake. 

Table 3 Human body content, and deficient, typical, and rich sources of intakes of ultratrace elements ...

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