Foods phosphorus

Phosphorus is acquired by eating phosphorus-rich foods. Phosphorus is absorbed in the GI tract and excreted in urine and a small amount in feces. It is converted to phosphate in the body. 

Phosphorus compounds are very important as fertilizers (world use 1976/77 27-3 megatonnes as P2O5) but are widely used in matches, pesticides, special glasses and china ware, alloys (sleels. phosphor bronze), and metal treating (10%), detergents (40%), electrical components (e.g. GaP), foods and drinks (15%). Phosphates are an essential constituent of living organisms. U.S. production of phosphorus 1982 372 000 tonnes. 

Phosphorus. Eighty-five percent of the phosphoms, the second most abundant element in the human body, is located in bones and teeth (24,35). Whereas there is constant exchange of calcium and phosphoms between bones and blood, there is very Httle turnover in teeth (25). The Ca P ratio in bones is constant at about 2 1. Every tissue and cell contains phosphoms, generally as a salt or ester of mono-, di-, or tribasic phosphoric acid, as phosphoHpids, or as phosphorylated sugars (24). Phosphoms is involved in a large number and wide variety of metaboHc functions. Examples are carbohydrate metaboHsm (36,37), adenosine triphosphate (ATP) from fatty acid metaboHsm (38), and oxidative phosphorylation (36,39). Common food sources rich in phosphoms are Hsted in Table 5 (see also Phosphorus compounds). 

Table 5. Common Food Sources Rich in Phosphorus ...

P4 Oio(.y) -F 6H2 0(/) 4H3 POio(<2 ( ) More than 80% of the elemental phosphorus produced is converted to phosphoric acid. This pure product, which constitutes about 10% of the total industrial output of phosphoric acid, is the starting material for making food additives, pharmaceuticals, and detergents. 

Rodriguez-Otero, J. L., Paseiro, P., Simal, J., and Cepeda, A. (1994). Mineral content of the honeys produced in Galicia (north-west Spain). Food Chem. 49,169-171. Rodriguez-Otero, J. L., Paseiro, P., Simal, J., Terradillos, L., and Cepeda, A. (1995). Silicon, phosphorus, sulphur, chlorine and ash contents of Spanish commercial honeys. Z. Lebensm. Unters. Forsch. 200, 233-234. 

J. Wasaki, M. Ando, K. Ozawa, M. Omura, M. Osaki, H. Ito, H. Matsui, and T. Tadano, Properties of secretory acid phosphatase from lupin roots under phosphorus-deficient conditions, Plant Nutrition for Sustainable Food Production and Environment (T, Ando, K. Fujita, T. Mae, H. Matsumoto, S. Mori, and J. Sekiya, eds), Kluwer Academic Publishers, Dordrecht, 1997, p. 295. 

Universal and selective detectors, linked to GC or LC systems, have remained the predominant choice of analysts for the past two decades for the determination of pesticide residues in food. Although the introduction of bench-top mass spectrometers has enabled analysts to produce more unequivocal residue data for most pesticides, in many laboratories the use of selective detection methods, such as flame photometric detection (FPD), electron capture detection (BCD) and alkali flame ionization detection (AFID) or nitrogen-phosphorus detection (NPD), continues. Many of the new technologies associated with the on-going development of instrumental methods are discussed. However, the main objective of this section is to describe modern techniques that have been demonstrated to be of use to the pesticide residue analyst. 

The first-line treatment for the management of hyperphosphatemia is dietary phosphorus restriction to 800 to 1000 mg per day in patients with stage 3 CKD or higher who have phosphorus levels at the upper limit of the normal range or elevated iPTH levels.39 Foods high in phosphorus are also high in protein, which can make it difficult to restrict phosphorus intake while maintaining adequate protein intake to avoid... 

The organics contaminants, whose concentration is usually expressed in terms of biochemical oxygen demand (BOD), are utilized as food for the bacteria. Besides oxygen, nutrients (nitrogen and phosphorus) are also needed by the bacteria for its metabolism. The concentrations of oxygen, bacteria, organic contaminants, and nutrients, as well as other factors, have an affect on the biological treatment rate. 

Jiao Y., Bailey L.D., Grant C.A. Effects of phosphorus and zinc fertilizer on cadmium uptake and distribution in flax and durum wheat. J Sci Food Agri 2004 84 777-785. 

Milk is an excellent source of calcium, phosphorus, riboflavin (vitamin B2), thiamine (vitamin Bl) and vitamin B12, and a valuable source of folate, niacin, magnesium and zinc (Food Standards Agency, 2002). In particular, dairy products are an important source of calcium, which is vital for maintaining optimal bone health in humans (Prentice, 2004). The vitamins and minerals it provides are all bioavailable (i.e. available for absorption and use by the body) and thus milk consumption in humans increases the chances of achieving nutritional recommendations for daily vitamins and mineral intake (Bellew et al., 2000). 

The most important acid containing phosphorus is orthophosphoric acid, H3P04. This is the acid usually indicated when the name phosphoric acid is used in most contexts. Approximately 30 billion pounds of this acid are produced annually. The commercial form of the acid is usually a solution containing 85% acid. The process used to produce phosphoric acid is related to the intended use of the acid. If the acid is intended for use in foods, it is prepared by burning phosphorus and dissolving the product in water. 

Used industrially as a chemical intermediate in the production of rayon, carbon tetrachloride, xanthogenates, flotation agents, and pesticides used in the cold vulcanization of vulcanized rubber, in adhesive compositions for food packaging as a solvent for phosphorus, sulfur, selenium, bromine, iodine, fats, resins, rubbers, waxes, lacquers, camphor, resins and in the production of optical glass, paints, enamels, varnishes, paint removers, tallow, putty preservatives, rubber cement, soil disinfectants, explosives, rocket fuel, and electronic vacuum tubes. 

The toxic impurities of phosphorus ores are conserved in phosphorus fertilizers produced from these ores, and finally they are accumulated in the agroecosystems (see Chapter 13). These pollutants can enter into biogeochemical food webs and increase the ecological risk especially under acid soils distributed in many regions of the World (Europe, Asia and North and South America). 

Additive organic phosphorus flame retardants, 11 488-489 Additives. See also Flocculating agents Food additives... 

Increasing both dietary Ca and P causes a decrease in PTH-mediated bone resorption polyphosphates and phosphorus in food cause greater reductions than does inorganic orthophosphate, as these sources are slowly released in digestion. 

Dietary phosphorus exerts variable influence on calcium loss depending on the nature of the dietary protein. Humans fed food containing abundant phosphorus to calcium excreted little more calcium unless the meat content of the diet changed markedly. 

Meat and such high protein plant foods as soy are excellent sources of phosphorus as well as protein. The phosphorus in meat is readily absorbed from the gastrointestinal tract however, much of the phosphorus in plant products is in a bound form which may inhibit the absorption of calcium as well as phosphorus. This study was designed to determine the effect of different levels of calcium and phosphorus with plant protein or animal protein on bone breaking strength and calcium and phosphorus utilization of weanling mice. 

Experimental. A second study was conducted with nine postmenopausal women age 51-65 yr. The subjects were fed standardized meals for 19 weeks. The mean composition for the 7-day menus of natural foods as % of total calories was 15% protein, 50% carbohydrate, 35% fat with a P/S ratio of 0.7, 10 g/day crude fiber, and less than 300 mg/day cholesterol. In addition, the diets supplied 1289 mg calcium, 1832 mg phosphorus, 2561 mg sodium and 5099 mg potassium daily. The diets met the RDA for all other nutrients. Calorie levels were adjusted to maintain body weight. The experimental meals were fed during the last six weeks of this 19-week period. No more than one liquid meal was consumed by each subject in one week. Fasting and postprandial samples of blood and urine were collected as in the previous study. Diuresis was induced by scheduled consumption of water. 

As can be seen from the results in Table V, fluoride levels in plasma, liver and kidney increased 3 to 8 times but there was no significant effect on the calcium or phosphorus content, although the kidney Ca level in fluoride treated rats was 40 higher than in the controls. Whereas the normal exposure to fluoride from air, food and water did not cause any increase in soft tissue levels, more than ten times the normal levels in soft tissues, including liver and kidney, were found in human fatalities due to fluoride poisoning (15). 

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