Molybdenum uptake, absorption and excretion in humans

Human parenteral nutrition micronutrient supplementation

Background: This work represents the first part of a progressive review of AuSPEN's 1999 Guidelines for Provision of Micronutrient Supplementation in Adult Patients receiving Parenteral [intravenous] Nutrition, in recognition of the developments in the literature on this  since that time.

Methods: A systematic literature review was undertaken and recommendations were made based on the available evidence and with consideration to specific elements of the Australian and New Zealand practice environment. The strength of evidence underpinning each recommendation was assessed. External reviewers provided feedback on the guidelines using the AGREE II tool.

Results: Reduced doses of manganese, copper, chromium and molybdenum, and an increased dose of selenium are recommended when compared with the 1999 guidelines. Currently the composition of available multi-trace element formulations is recognised as an obstacle to aligning these guidelines with practice. A paucity of available literature and limitations with currently available methods of monitoring trace element status are acknowledged. The currently unknown clinical impact of changes to trace element contamination of parenteral solutions with contemporary practices highlights need for research and clinical vigilance in this area of nutrition support practice.

Conclusions: Trace elements are essential and should be provided daily to patients receiving parenteral nutrition. Monitoring is generally only required in longer term parenteral nutrition, however should be determined on an individual basis. Industry is encouraged to modify existing multi-trace element solutions available in Australia and New Zealand to reflect changes in the literature outlined in these guidelines. Areas requiring research are highlighted

Osland, E. J., Ali, A., Isenring, E., Ball, P., Davis, M., and Gillanders, L., Australasian Society for Parenteral and Enteral Nutrition guidelines for supplementation of trace elements during parenteral nutrition, Asia Pacific Journal of Clinical Nutrition, 2014, 23, 545-554.

Molybdenum ingestion and excretion in human beings

A very thorough study of Mo uptake and recommended levels is available.

Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc, Panel on Micronutrients, Subcommittees on Upper Reference Levels of Nutrients and of Interpretation and Use of Dietary Reference Intakes, and the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, National Academy Press, 2001 Chapter 11 Molybdenum.

The Recommended Dietary Allowance for adult men and women is 45 microg/day. The average dietary intake of molybdenum by adult men is 109 microg/day and women is 76 microg/day. The Tolerable Upper Intake Level is 2000 microg/day, a level based on impaired reproduction and growth in animals. The main quantitative conclusions are summarised here. The reader should consult the original for definitions, general discussion and methodology.  

Molybdenum intake levels humans
 Adequate intake (AI)/ microg/dayEstimated average requirement (EAR) microg/dayRecommended dietary allowance (RDA) microg/dayTolerable upper intake level (UL) microgMo/day
Infants        
0-6 months 2      
7-12 3      
children        
1 -3   13 17 300
4-8   17 22 600
boys and girls        
9-13   26 34 1100
14-18   33 43 1700
men and women        
>18   34 45 2000
pregnancy        
14-18   40 50 1700
=>19   40 50 2000
lactation        
14-18   35 50 1700
=>19   36 50 2000

Infants

Plasma studies were conducted in healthy breast-fed infants and in patients with phenylketonuria at the age of 4 weeks, and the plasma investigations were repeated at the ages of 4 and 12 months. Molybdenum concentrations in formulas exceed those in human milk. Molybdenum intake and retention in all infants with phenylketonuria were more than 18 times those of breast-fed infants.The plasma concentrations reflected these differences. A median of 0.04 mu g/l was assessed in breast-fed infants at 4 weeks and less than 0.02 mu g/l at 4 months of age. Comparative results of infants with phenylketonuria were 2.9 mu g/l and 2.5 mu g/l, respectively. There were no significant differences between the groups at 12 months of age. The phenylketonuria diets investigated showed excessive retention and plasma concentrations of the essential trace element molybdenum in early infancy. In view of these findings, the present practice of molybdenum fortification should be revised

Sievers, E., Arpe, T., Schleyerbach, U., and Schaub, J., Molybdenum supplementation in phenylketonuria diets: Adequate in early infancy?, Journal of Paediatric Gastroenterology and Nutrition, 2000, 31, 57-62.

Daily Molybdenum Intake and Excretion Rates in Adults

Daily Molybdenum Intake and Excretion Rates in Adults
 Intake /microgExcretion /microg
Food 335  
Drinking water 2.8  
Air <1.0  
Total 338  
Urine   190
Feces   125
Perspiration   20
Total   335

Lever, J., and Bibr., Effects of Molybdenum on the Organism (A Review) , 1986.

A compartmental model of molybdenum metabolism based on stable isotope excretion patterns was developed. Molybdenum is an essential trace element in humans, with an estimated safe and adequate daily dietary intake (ESADDI) of 75-250 microg Mo/d. Four adult men were fed low molybdenum diets, 22 microg Mo/d, for a period of 102 d. The stable isotopes 97Mo and 100Mo were administered in intravenous and oral doses respectively at selected intervals. The resulting 6 d cumulative urinary and faecal isotope excretion data were used to model molybdenum metabolism using SAAM/CONSAM software. A kinetic model, including gastrointestinal (GI),plasma, slow-turnover tissue and fast-turnover tissue compartments, accurately simulated the observed pattern of urinary and faecal excretion for both stable isotopes in all four subjects. Residence time for molybdenum in the GI tract was estimated at 1.7 0.4 d. Predicted residence time for plasma molybdenum was 224 min, whereas slow-turnover tissue (possibly hepatic) retention averaged 58 16 d. The model thus permitted estimation of kinetic parameters for molybdenum metabolism in tissues not readily accessible or measurable in humans.

Thompson, K.H., Turnlund, J.R., Kinetic-Model Of Molybdenum Metabolism Developed From Dual Stable-Isotope Excretion In Men Consuming A Low Molybdenum Diet, Journal Of Nutrition, 1996, 126, 963-972.

The gastrointestinal tract readily absorbs soluble, but not insoluble, molybdenum compounds [Wester et al., 1971]. Absorption rate of molybdenum from the diet of both patients and healthy volunteers averaged about 50% in one study and 88-93% in another study in which the patients received 22-1490 microg Mo/d for 24 days.

Wester, P.O., Trace element balances in two cases of pancreatic insufficiency. Acta Med. Scand., 1971;190,155-161.

The Mo intake of adults in Germany and Mexico was determined in food duplicate samples by inductively coupled plasma atomic emission spectrometry [Holzinger et al. 1998]. Each test population consisted of seven men and seven women and also 10 female and 10 male vegetarians and two Mexican test groups. Molybdenum intake of adults with mixed diets increased from 1988 to 1996. German women with a mixed diet consumed 89 mu g/ din 1996 and men 100 mu g/ d, In comparison, female and male vegetarians consumed 179 mu g /d and 170 mu g/ d. Mexican women consumed 162 mu g /d and Mexican men 208 mu g /d. The Mo requirement of adults, 25 mu g /d, is met by normal intake, An intake of 150 mu g /kg body weight may be toxic for humans, Therefore, people in Germany and Mexico are not endangered by Mo exposure.

Holzinger, S., Anke, M., Rohrig, B., Gonzalez, D., Molybdenum intake of adults in Germany and Mexico, Analyst, 1998,3, 447-450.

When Mo in aqueous solution (0.5 - 5 mg Mo in ca 0.005M HCl) was administered to 3 healthy human volunteers on a total of 15 occasions, at doses up to 1 mg almost complete uptake (by intestinal absorption) of Mo was observed and only a slight decrease (< 30%) for higher doses [Werner et al., 1998]. Addition of black tea reduced the absorbed fraction by about a factor of ten. Mo uptake (intestinal absorption) from intrinsically labelled cress (60%)was less than the Mo uptake from extrinsically labelled cress (75%) and aqueous solutions (100%). Even less Mo (below 45%) was absorbed from an extrinsically labelled composite meal comprising chicken, vegetables and noodles).

Werner, E., Giussani, A., Heinrichs, U., Roth, P., Greim, H., Biokinetic studies in humans with stable isotopes as tracers. Part 2: Uptake of molybdenum from aqueous solutions and labelled foodstuffs, Isotopes In Environmental And Health Studies, 1998,.34, 297-301.

Molybdenum biokinetics in humans is of interest in connexion with the fate in the body of the radionuclide 99Mo [Giussani et al., 1998] which is used as a 99 mTc generator in nuclear medicine and may be released after accidents in nuclear power plants. (In Chernobyl ca 6% of the total radioactivity released within the first 10 d was due to 99Mo.). The aim in developing a biokinetic model is to provide an estimate of the number of radioactive transformations taking place in a given period in the organs where the radionuclides are distributed. Such studies, undertaken in humans with the stable isotopes 95Mo and 96Mo provide also data on the absorption, excretion of molybdenum and its distribution in the body. Values of the fractional transfer coefficients, e.g. from the stomach, to the intestines, the kidney and the bladder are given for Mo supplied in aqueous solution (chloride) (orally, 5.2 to 55 microg kg-1 body weight), in a foodstuff (cress), and intravenously.

The conclusions of these and related and earlier experiments are:

Intestinal absorption of Mo supplied as an aqueous solution is almost complete (>90%, Mo < 5 mg).

Intestinal absorption of Mo supplied with a solid meal is less than 50% of the administered amount.

Plasma clearance is fast:: mean sojourn time in the transfer compartment is ca 100 min.

Urinary excretion regulates rapidly the body content of Mo and its pattern is independent of the administered form (injection or ingestion, extrinsic or intrinsic tracer). The excreted amount rises strongly with increasing Mo dietary level. Thus when 33 microgMo were injected into human volunteers the excreted amounts (microg) in the urine within 18 d at increasing daily diet Mo values (microg) were: 13 at 22 in diet, 28 at 120 and 31 at 1500.

Gastric emptying is much slower with solid meals than with aqueous solutions of Mo: residence half-times for solids 30 min, for liquids 10 min.

Mean residence time for Mo in the kidney was 14 d.

Giussani, A., Cantone, M.C., deBartolo, D., Roth, P., Werner, E., A revised model of molybdenum biokinetics in humans for application in radiation protection, Health Physics, 1998, 75, 479-486.

In a study of molybdenum uptake by men and women absorption and excretion of molybdenum in foodstuffs and molybdenum added to the diet were compared. Molybdenum (100 mu g Mo per meal) in soy was less available than molybdenum added to the diet, but the molybdenum in kale was as available as molybdenum added to the diet. Once absorbed, urinary excretion was not significantly different for soy, kale, and extrinsic molybdenum [Turnlund et al., 1999].

Turnlund, J.R., Weaver, C.M., Kim, S.K., Keyes, W.R., Gizaw, Y., Thompson, K.H., Peiffer, G.L., Molybdenum absorption and utilization in humans from soy and kale intrinsically labeled with stable isotopes of molybdenum, American Journal Of Clinical Nutrition, 1999, 69, 1217-1223.

Dose coefficients for ingestion of radionuclides of molybdenum from members of the public have been calculated according to the guidelines using a revised biokinetic model. A constant daily intake of 200 microg/day is assumed. The results obtained for the effective dose do not differ remarkably from the estimates. However, considerable deviations are observed for the equivalent dose to some individual organs; for example, the dose coefficient for colon after ingestion of Mo-99 in solid form is about 7 times higher than the International Commission on Radiological Protection value, whereas for other organs the new estimates are about one tenth. In agreement with earlier work liver and kidney are the organs where molybdenum is more easily found with concentrations (microg/g wet weight): for liver, 0.5 to 1.0; kidney, average 0.3, range 0.2 – 0.4.

Giussani, A., Cantone, M.C., deBartolo, D., Roth, P., Werner, E., Internal dose for ingestion of molybdenum radionuclides based on a revised biokinetic model, Health Physics, 2000, 78, 1, 46-52.

Plasma molybdenum and dietary uptake

An isotope dilution method was developed to determine molybdenum in 0.5 mL blood plasma by ICP-MS. The effect of dietary intake on plasma molybdenum was determined for twelve young men (ages 22–33 y). This is an important paper which includes a discussion of the instrumentation and experimental procedures, including the avoidance of contamination, required to determine accurately molybdenum at the low levels found in plasma. It is suggested that earlier values for molybdenum in whole blood may be as much as ten times too high. Some typical results are these.

For subjects consuming a very low Mo diet (22 microg/day) plasma molybdenum decreased from 8.2 ± 0.5 to 6.1 ± 0.5 nmol/L after 13 days of low molybdenum intake and was 5.1 ± 0.5 nmol/L after 24 days.

Another group consumed the low molybdenum diet for 102 days followed by high molybdenum (467 microkg/day for 18 days and the plasma molybdenum rose to 16.5 ± 0.6 nmol/L during the high molybdenum period.

The results demonstrate that, in contrast to most other essential minerals, plasma molybdenum reflects low and high dietary molybdenum intakes within 14 days and may a useful indicator of low and high dietary intakes.

Turnlund, J.R. and Keyes, W. R., Plasma molybdenum reflects dietary molybdenum intake, Journal of Nutritional Biochemistry, 2004, 15, 90-95.

Mo uptake humans

The intestinal absorption of molybdenum in healthy human volunteers has been measured by simultaneous oral and intravenous administration of the stable isotopes 95Mo and 96Mo, and the results were analysed using the convolution integral technique. The results showed that molybdenum ingested in liquid form was rapidly and totally absorbed into the circulation under ordinary intake regimes. The rates and extent of absorption were lower for composite meals, and also for increasing levels of administration. This information can be helpful in the application of the new ICRP model of the human alimentary tract.

Giussani, A., Arogunjo, A. M., Cantone, M. C., Tavola, F., and Veronese, I., Rates of intestinal absorption of molybdenum in humans, Applied Radiation and Isotopes, 2006, 64, 639-644.

The intestinal uptake, systemic kinetics and urinary excretion of molybdenum in 17 healthy human volunteers has been studied using stable isotopes of molybdenum measuring their concentrations by activation analysis and mass spectrometry in blood plasma (96Mo) following intravenous injection and urine (95Mo) following oral administration. Molybdenum was administered in water (up to 5 mg Mo in 100 ml), and 0.5  1 mg Mo in black tea (100 ml) mg and in vegetables (cress and green salad) and solid food (baby formula, tomatoes, bean soup). The object of the experiments was to develop a compartmental model for the systemic kinetics of molybdenum. The main observations were

Molybdenum was eliminated very rapidly from the circulation. Urinary excretion of molybdenum was intense and rapid in the few hours after incorporation. After 24 h excretion rates were negligible.

Intestinal absorption of the oral tracer Mo into the systemic circulation depended on the form in which it was administered reflecting its bioavailability

in water solution 100% absorption for administration up to 1 mg,

with solid foods reduced to 50% absorption

with black tea 10% or less absorption.

Only the process of renal excretion is influenced by the total amount of molybdenum in the systemic circulation.

The amount eliminated via the renal pathway was observed to be dependent on several factors: form and modality of administration and the total amount of circulating molybdenum.

Modelling urinary excretion of molybdenum after oral and intravenous administration of stable tracers. Giussani A, Cantone MC, Höllriegl V, Oeh U, Tavola F, Veronese I. Radiat Prot Dosimetry. 2007 Jun 19; [Epub ahead of print]

An expanded compartmental model of molybdenum kinetics to determine rates of molybdenum distribution during molybdenum depletion and repletion was developed. The model was based on a clinical study in which 4 men consumed a low-molybdenum diet of 22 mu g/d (0.23 mu mol/d) for 102 d, followed by a high molybdenum diet of 467 mu g/d (4.9 mu mol/d) for 18 d. Stable isotopes 100Mo and 97Mo were administered orally and intravenously, respectively, at several time points during the study, and serial samples of plasma, urine, and feces were analyzed for 100Mo and 97Mo , and total Mo. Based on plasma, urine, and fecal molybdenum levels, kinetic parameters of distribution and elimination were determined. The rates of molybdenum distribution and elimination were different during depletion and repletion. During high intake, urinary molybdenum excretion was greater than during low intake. Fractional tissue storage of molybdenum was lower during high intake than during low intake. Low intake results in an adaptation to conserve body Mo, and that high intake results in an adaptation to eliminate Mo. The model also suggested that food-bound molybdenum was approximately 16% less bioavailable than purified Mo. The model suggested that an intake of 43 mu g/d (0.45 mu mol/d) would be sufficient to maintain plasma molybdenum levels at steady state. This is a minimum estimate because subjects in this study were in a molybdenum-sparing state. These findings provide an understanding of the adaptations in molybdenum metabolism that take place during depletion and repletion

Novotny, J. A. and Turnlund, J. R., Molybdenum kinetics in men differ during molybdenum depletion and repletion, Journal of Nutrition, 2006, 136, 953-957.

The objectives of this study were to determine physiologic adaptations that occur when humans are exposed to a wide range of molybdenum intake levels and to identify the pathways that are influenced by dietary intake. Four males consumed each of 5 daily molybdenum intakes of 22, 72, 121, 467, and 1490 microg/d (0.23,0.75, 1.3, 4.9, and 15.5 micromol/d) for 24 d each. During each treatment period, oral and intravenous doses of (100)Mo and (97)Mo were administered. Serial plasma, urine, and fecal samples were analyzed for labeled and unlabeled molybdenum. Compartmental modeling was used to determine rates of distribution and elimination at each dietary intake level. Three pathways were sensitive to daily molybdenum intake. With increasing intake, absorption and urinary molybdenum excretion increased, whereas the fraction deposited in tissues decreased. Kinetic analysis suggested a daily intake of 115-120 microg/d (1.20-1.25 micromol/d) would maintain initial plasma molybdenum levels at their prestudy values and that their prestudy dietary intake was well above the Recommended Dietary Allowance of 45 microg/d. The physiological adaptations to changing intake that the model demonstrated may help prevent molybdenum deficiency and toxicity.

Molybdenum intake influences molybdenum kinetics in men. Novotny JA, Turnlund JR. J Trace Elem Med Biol. 2007;21(1):8-16. Epub 2007.

Molybdenum metabolism of premature infants

The supplementation of formulas for premature infants with Mo should be rescinded until there is evidence for its necessity

Plasma was collected at 3, 16, and 52 wk and

72 h balances were performed at 3 wk of age.

For premature infants

n = 18,

gestational age less than or equal to 32 wk,

birth weight less than or equal to 1500 g

Increased Mo intake and low relative urinary excretion resulted in a retention of 4.4 (0.99-7.77) mug Mo/kg initially in premature infants (median, range). Parallel plasma concentrations were 5.5 (2.5- 7.3) mug Mo/L,, declining to 2.36 (0.73-3.87) mug Mo/L at 4 wk.

For healthy formula-fed term infants

n = 14

Initial plasma 1.49 (0.29-1.7) mug Mo/L (p < 0.05), with no significant differences later.

Sievers, E., Schleyerbach, U., Arpe, T., Garbe-Schonberg, D., and Schaub, J., Molybdenum supply of very low-birth-weight premature infants during the first months of life, Biological Trace Element Research, 2001, 80, 97-106.

Mo balances were assessed for formula Mo concentrations from 0.125 to 2.704 mu mol/l.

For infants with a "low" Mo intake 0.024 (0.020-0.035) mu mol/ kg per day

urinary excretion was 0.02 (0.008-0.045) mu mol/kg per day

retention 0.0006 (-0.03 to 0.008) mu mol/kg per day.

For infants with a "high" intake 0.284 (0.2270.487) mu mol/kg per day,

urinary excretion was 0.243 (0.118-0.378)

retention of 0.022 (-71.1 to 141.44) mu mol/kg per day.

Since the median urinary excretion exceeded 60% of the Mo intake at low and high intakes, sufficient resorption but minimal retention was assessed at low intakes of Mo. In view of the limited knowledge of long-term exposure to an elevated molybdenum intake and the substantial retention observed at higher intakes, upper limits should be set for molybdenum concentrations in preterm infant formulas

Sievers, E., Oldigs, H. D., Dorner, K., Kollmann, M., and Scbaub, J., Molybdenum balance studies in premature male infants, European Journal of Pediatrics, 2001, 160, 109-113.

Molybdenum dietary uptake

Recommended dietary allowances of molybdenum

A very thorough study of Mo uptake and recommended levels is available here. The Recommended Dietary Allowance for adult men and women is 45 microg/day. The average dietary intake of molybdenum by adult men is 109 microg/day and women is 76 microg/day. The Tolerable Upper Intake Level is 2000 microg/day, a level based on impaired reproduction and growth in animals. The main quantitative conclusions are summarised here. The reader should consult the original for definitions, general discussion and methodology.

Recommended dietary allowances of molybdenum
 Adequate intake (AI)/ microg/dayEstimated average requirement (EAR) /microg/dayRecommended dietary allowance (RDA) /microg/dayTolerable upper intake level (UL) /microgMo/day
Infants        
0-6 months 2      
7-12 3      
children        
1 -3   13 17 300
4-8   17 22 600
boys and girls        
9-13   26 34 1100
14-18   33 43 1700
men and women        
>18   34 45 2000
pregnancy        
14-18   40 50 1700
=>19   40 50 2000
lactation        
14-18   35 50 1700
=>19   36 50 2000

Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc, Panel on Micronutrients, Subcommittees on Upper Reference Levels of Nutrients and of Interpretation and Use of Dietary Reference Intakes, and the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, National Academy Press, 2001 Chapter 11 Molybdenum.

Bioaccessibility of micron-sized powder particles of molybdenum metal, Mark iron metal, molybdenum oxides and ferromolybdenum - Importance of surface oxides

The European chemical framework REACH requires that hazards and risks posed by chemicals, including alloys and metals, that are manufactured, imported or used in different products (substances or articles) are identified and proven safe for humans and the environment. Metals and alloys need hence to be investigated on their extent of released metals (bioaccessibility) in biologically relevant environments. Read-across from available studies may be used for similar materials. This study investigates the release of molybdenum and iron from powder particles of molybdenum metal (Mo), a ferromolybdenum alloy (FeMo), an iron metal powder (Fe), MoO2, and MoO3 in different synthetic body fluids of pH ranging from 1.5 to 7.4 and of different composition. Spectroscopic tools and cyclic voltammetry have been employed to characterize surface oxides, microscopy, light scattering and nitrogen absorption for particle characterization, and atomic absorption spectroscopy to quantify released amounts of metals. The release of molybdenum from the Mo powder generally increased with pH and was influenced by the fluid composition. The mixed iron and molybdenum surface oxide of the FeMo powder acted as a barrier both at acidic and weakly alkaline conditions. These findings underline the importance of the surface oxide characteristics for the bioaccessibility of metal alloys. (C) 2015 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Morsdorf, A., Wallinder, I. O., and Hedberg, Y.,Bioaccessibility of micron-sized powder particles of molybdenum metal, Mark iron metal, molybdenum oxides and ferromolybdenum - Importance of surface oxides, Regulatory Toxicology and Pharmacology, 2015, 72, 447-457.

Surface and Subsurface Analyses of Metal-on-Polyethylene Total Hip Replacement Retrievals

Metal-on-polyethylene (MOP) articulations are one of the most reliable implanted hip prostheses. Unfortunately, long-term failure remains an obstacle to the service life. There is a lack of higher resolution research investigating the metallic surface component of MOP hip implants. This study investigates the surface and subsurface features of metallic cobalt chromium molybdenum alloy (CoCrMo) femoral head components from failed MOP retrievals. Unused prostheses were used for comparison to differentiate between wear-induced defects and imperfections incurred during implant manufacturing. The predominant scratch morphology observed on the non-implanted references was shallow and linear, whereas the scratches on the retrievals consisted of largely nonlinear, irregular scratches of varying depth (up to 150 nm in retrievals and up to 60 nm in reference samples). Characteristic hard phases were observed on the surface and subsurface material of the cast samples. Across all samples, a 100-400 nm thick nanocrystalline layer was visible in the immediate subsurface microstructure. Although observation of the nanocrystalline layer has been reported in metal-on-metal articulations, its presence in MOP retrievals and unimplanted prostheses has not been extensively examined. The results suggest that manufacturing-induced surface and subsurface microstructural features are present in MOP hip prostheses prior to implantation and naturally, these imperfections may influence the in vivo wear processes after implantation.

Vuong, V., Pettersson, M., Persson, C., Larsson, S., Grandfield, K., and Engqvist, H.,Surface and Subsurface Analyses of Metal-on-Polyethylene Total Hip Replacement Retrievals, Annals of biomedical engineering, 2015.

Absorption and excretion of molybdenum

Variability of Metal Levels in Spot, First Morning, and 24-Hour Urine Samples over a 3-Month Period in Healthy Adult Chinese Men

BACKGROUND: Metals in single spot urine samples are often used to estimate individual exposure in human studies. However, measurements in urine could vary greatly over time due to the variable exposure, potentially leading to exposure misclassification. OBJECTIVE: To examine the variability of metal levels in the urine of 11 men who provided 529 samples on 8 days during a 3-month period, which corresponds to the duration of spermatogenesis.

METHOD: The urinary levels of arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), lead (Pb), molybdenum (Mo) and nickel (Ni) were measured using inductively coupled plasma-mass spectrometry. We calculated the intraclass correlation coefficients (ICCs) to assess the reproducibility of metal measures and computed the sensitivity and specificity to evaluate how well spot urine samples determined the individuals' 3-month average exposure.

RESULTS: Fair to good reproducibility was observed for the serial measurements of Cd (ICC=0.53) in spot samples collected during the 3-month period, whereas the serial measurements of As, Co, Cu, Pb, Mo and Ni showed poor reproducibility (ICCs=0.01-0.29). Use of single spot urine samples to classify the high (top 33%) 3-month average metal levels had uniformly high specificities (0.70-0.84) but relatively low sensitivities (0.40-0.57), except for Cd (0.77). The minimum number of specimens (k) required to estimate the participant-specific mean for the seven metals within 20% of the "true" values ranged from 3 for Cd to 27 for Ni.

CONCLUSIONS: The high variability observed in the urinary levels of As, Co, Cu, Pb, Mo and Ni suggest that a single measurement provides only a brief snapshot in time of the exposure levels of an individual, which can result in a moderate degree of exposure misclassification.

Wang, Y. X., Feng, W., Zeng, Q., Sun, Y., Wang, P., You, L., Yang, P., Huang, Z., Yu, S. L., and Lu, W. Q.,Variability of Metal Levels in Spot, First Morning, and 24-Hour Urine Samples over a 3-Month Period in Healthy Adult Chinese Men, Environmental health perspectives, 2015.

 

Absorption and excretion of molybdenum

Intake of copper and molybdenum in Korean adults

This study aimed to analyze the amounts of copper, selenium, and molybdenum among trace minerals in foods and to evaluate their daily intakes in Korean adults. Contents of copper, selenium, and molybdenum in 366 varieties of foods commonly consumed by Koreans were analyzed using inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry, techniques with low detection limits as well as high reproducibility and precision. Next, we evaluated the status of trace mineral intake using the 24-h recall method after conducting anthropometric measurements on 249 male and 344 female adults aged 20 or older. The average daily energy intake for males was 7,452.8 kJ, significantly higher than the 6,118.3 kJ for females (p < 0.001). The average daily copper, selenium, and molybdenum intakes by males were 1,156.7, 135.5, and 12.2 mu g, respectively, compared to 1,028.5, 122.9, and 10.1 mu g, respectively, by females. In males, the intake levels of copper and molybdenum were both significantly higher than in females. By continuously evaluating intake levels in this manner, it is anticipated that reference intakes of trace minerals will be established

Choi, M. K., Kang, M. H., and Kim, M. H., The Analysis of Copper, Selenium, and Molybdenum Contents in Frequently Consumed Foods and an Estimation of Their Daily Intake in Korean Adults, Biological Trace Element Research, 2009, 128, 104-117.

Recommended daily allowances of molybdenum

Recommended daily allowances 0.15 – 0.5 mg/d
Min daily requirement Mo 2 microg Mo/kg body weight
WHO

A recommended daily allowance of molybdenum for an adult has been established at 0.2 mg [Dulce, 1968]. In addition daily molybdenum intakes from drinking water and ambient air are almost neglible and should be considered only in molybdenum mining areas. A rapid rate of molybdenum excretion has been observed after the administration of high doses and it has been suggested that this observation is likely to represent one of the defence and regulatory mechanisms of the organism [Lener, 1978].

Dulce, H. J., D. Zahnaerztl. Z., 1968, 23, 101.
Lener, J., Molybden jako faktor zivotního prostredíz hlediska jeho nekterých úcinku. Doktorská disertacní práce, Praha, 1978.

Four young men were fed a low-molybdenum diet (22 microg/d) for 102 d followed by 18 d of the same diet supplemented to contain 467 microg/d. The study was to determine the minimum dietary molybdenum requirement of healthy young men. Stable isotopes of molybdenum were used as tracers. The study demonstrated that subjects could not consistently attain balance with the low-molybdenum diet, but balance improved with time, and no signs of molybdenum deficiency were observed. Molybdenum was very efficiently absorbed at both intakes of dietary molybdenum and urinary excretion increased as dietary molybdenum increased. Molybdenum turnover was significantly slower when dietary molybdenum was low. The minimum dietary molybdenum requirement is approximate 25 microg/d less than the current recommended amount of 75 microg/d [Turnlund et al., 1995.]

Turnlund, J.R., Keyes, W.R., Peiffer, G.L., Chiang, G., Molybdenum Absorption, Excretion, And Retention Studied With Stable Isotopes In Young Men During Depletion And Repletion, American Journal Of Clinical Nutrition, 1995, 61,1102-1109.

Reference values for molybdenum intake

A set of reference values has been established for chromium, copper, iodine, iron, manganese, molybdenum, and zinc to replace Recommended Dietary Allowances (RDAs), Estimated Safe and Adequate Daily Dietary Intakes published in 1989. AU RDAs, Adequate Intakes (AIs), and Tolerable Upper Intake Levels (ULs] reported are summarized, commented and compared with the DACH reference values 2000. For some elements including molybdenum, ULs have been established.

Reference values for molybdenum intake
AgeDRI 2001 RDA /microgMo/dayAgeDACH Reference value 2000 /microgMo/dayAgeTolerable upper intake levels /microgMo/day
0 – 6 Month. 2 0 - <4 Month 7 0 – 6 Month. k.A.
7 – 12 3 4 - <12 20 - 40 7 – 12 Month k.A.
1 – 3 Year 17 1 - <4 Year 25 – 50 1 – 3 Year 300
4 – 8 22 4 - <7 30 – 75 4 – 8 600
9 – 13 34 7 - <10 40 - 80 9 – 13 1100
    10 - <13 50 - 100    
    13 - <15 50 – 100    
14 – 18 43 15 - <19 50 – 100 14 – 18 1700
19 – 50 45 19 - <25 50 – 100 Adult 2000
    25 - <51 50 – 100    
> 50 45 > 51 50 – 100 > 50  
Pregnant       Pregnant  
14 – 18 Year 50   50 - 100 14 – 18 Year 1700
> 18 50     > 18 2000
Lactating       Lactating  
14 – 18 Year 50   50 – 100 14 – 18 Year 1700
> 18 50     > 18 2000

Gassmann, B., Dietary reference intakes, report 4: Trace elements, Ernahrungs-Umschau, 2001, 48, 148-152.

Molybdenum recommended intake for premature infants

Molybdenum recommended intake for premature infants
StatusRecommended Mo intake microg/kg/day
transitional period 0-14d  
enteral 0.3
parenteral 0
stable/postdischarge periods  
enteral 0.3
parenteral 0.25

Mo in premature formula milk (170 microg/l) or breast milk (2-3 microg/l) gave similar plasma Mo concentrations. Urinary uric acid which reflects xanthine oxidase metabolism reduced by lower Mo intake from formula. Mo better adsorbed from human milk.

Zlotkin, S.H., Atkinson, S., Lockitch, G.,Trace-Elements In Nutrition For Premature-Infants, Clinics in Perinatology, 1995, 22, 223-240.

Mo deficiency in low-birth-weight infants

Low-birth-weight infants might be at risk for Mo deficiency because they are born before adequate stores for Mo can be acquired, they have rapid growthrequiring increased intakes, and they frequently receivesupplemental parenteral nutrition and total parenteralnutrition unsupplemented with molybdenum. Conclusions: The authors speculate that an intravenous intake of 1 mu g/kg/d (10nmol/kg/d) and an oral intake of 4-6 mu g/kg/d (40-60nmol/kg/d) would be adequate for the LBW infant.

Friel, J.K., MacDonald, A.C., Mercer, C.N., Belkhode, S.L., Downton, G., Kwa, P.G., Aziz, K., Andrews, W.L., Molybdenum requirements in low-birth-weight infants receivingparenteral and enteral nutrition, Journal Of Parenteral And Enteral Nutrition, 1999, 23, 3, 155-159.

Dietary intakes of molybdenum: recommended levels

Dietary intakes of molybdenum: recommended levels
 mg Mo/day
Safe [1] 0.5 - 1.0
Safe [2] 0.15 - 0.5
Harmful [1] >10
Human adults dietary minimum [3] 0.025

[1] Mertz, W., Molybdenum in the Environment, 1976, 1, Ch.18, Marcel Dekker, New York.
[2] National Academy of Sciences, Mineral Tolerance of Domestic Animals, 1980, Washington, D.C.
[3] Turnlund, J.R., Keyes, W.R., Peiffer, G.L., Chiang, G., Molybdenum Absorption, Excretion, And Retention Studied With Stable Isotopes In Young Men During Depletion And Repletion, American Journal Of Clinical Nutrition, 1995, 61,1102-1109.

Molybdenum retention in humans

Residence time for molybdenum in human adults
LocationRetention
GI tract 1.7 +/- 0.4 day
plasma 22 +/- 4 min
hepatic tissue 58 +/- 16 day

Thompson, K.H., Turnlund, J.R., Kinetic-Model Of Molybdenum Metabolism Developed From Dual Stable-Isotope Excretion In Men Consuming A Low Molybdenum Diet, Journal Of Nutrition, 1996, 126, 963-972.

Molybdenum in nutrition for premature infants

Molybdenum in Nutrition For Premature Infants
StatusRecommended Mo intake microg/kg/day
transitional period 0-14d  
enteral 0.3
parenteral 0
stable/postdischarge periods  
enteral 0.3
parenteral 0.25

Mo in premature formula milk (170 microg/l) or breast milk (2-3 microg/l) gave similar plasma Mo concentrations. Urinary uric acid which reflects xanthine oxidase metabolism reduced by lower Mo intake from formula. Mo better adsorbed from human milk.

Zlotkin, S.H., Atkinson, S., Lockitch, G.,Trace-Elements In Nutrition For Premature-Infants, Clinics in Perinatology, 1995, 22, 223-240.

Molybdenum excretion and molybdenum in urine

The molybdenum levels found in human urine samples determined spectrophotometrically were between 0.5-2.1 mu g/100 ml.

Amin, A.S., Determination of molybdenum in human urine by spectrophotometric method using thiazolylazo compounds as chromogenic reagents Analytical Letters, 1999, 32, 1575-1587.

Molybdenum in urine (summary) [Barceloux, 1999] US residents (National Health and Nutrition Examination Survey [NHANES III) a 95th percentile concentration of 168 microg Mol/L. The maximum concentration was 688 microg Mo/L.

Danish population: concentration in urine was 42.5 microg/L with an 95% reference interval of 10-124 microg/L.

Barceloux, D.G., Molybdenum, Journal Of Toxicology-Clinical Toxicology, 1999, 37, 231-237

Mean molybdenum creatinine levels in urine in 128 Danish inhabitants by ICP-MS were 42.5 mu g /l, (3.89 mu g Mo /mmol creatinine) using Mo-95 and 41.5 1 mu g/ l(3.81 mu g Mo /mmol creatinine) using Mo-98 [Sabbioni, 1998]. The precision was 8.6% and the recovery of added NIST 1643c certified reference material was 94%. The limit of detection was 0.2 mu g/ l. The difference between men and women reached the level of significance only after the values were corrected for the creatinine concentration, There was no influence of age on the Mo concentration Specific effects of different food and beverage intakes could not be demonstrated, with the exception of a positive correlation between butter consumption and Mo concentration.

Sabbioni, E., Iversen, B.S., Menne, C., White, M.A., Kristiansen, J., Christensen, J.M.,Inductively coupled plasma mass spectrometric determination of molybdenum in urine from a Danish population, Analyst, 1998, 123, 81-85.

The technique of electrothermal atomic absorption spectrometry has been developed and standardised for the determination of Mo and other metals in human urine. [Campillo et al., 1999].

Values for Mo from 4 subjects were

Molybdenum in urine
Subject1234
Mo in urine/microg/l 12 2.4 6.5 14
Mean +/-SD (n=9) 1 0.1 0.1 1

Average recovery of Mo added to a standard was 98.9% (range 95 - 103%).

The detection limit was 0.81 nanog Mo/l.

Campillo, N., Vinas, P., Lopez-Garcia, I., Hernandez-Cordoba, M., Determination of molybdenum, chromium and aluminium in human urine by electrothermal atomic absorption spectrometry using fast-programme methodology
Talanta, 1999, 48, 905-912

For molybdenum

Concentration range 5.8 – 313.9 microg/l (cf literature 4.7 – 152.2)

Mean 64+/-80

Median 25.6

The detection limit was 0.09 mug/l

The precision (RSD,%) was 2.8.

Wang, J.H., Hansen, E. H., and Gammelgaard, B., Flow injection on-line dilution for multi-element determination in human urine with detection by inductively coupled plasma mass spectrometry, Talanta, 2001, 55, 117-126

B.S. Iversen, T. Menne, M.A. White, J. Kristiansen, J.M. Christensen, E. Sabbioni, Analyst, 1998, 123, 81.)

Molybdenum in human urine was determined by direct dilution of the sample in doubly distilled water with 1% HNO3 (v/v) and inductively coupled mass spectrometry (ICP-MS). The detection limit was 0.2 mug/L Mo and the lower limit of quantification 0.6 mug/L. Mo in the urine of a population group 51 male 49 female in Tuscany, Italy, was determined:

Urinary molybdenum
 microg/lmicrog/g creatinine
Mean 54.1 44.8
Standard deviation 33.9 23.8
Highest 155.8 137.0
Lowest 11.1 7.4

Molybdenum level did NOT depend on gender, age, smoking and drinking habits. The variability is likely to depend on Mo intake which was not measured.

Minoia, C., Gatti, A., Aprea, C., Ronchi, A., Sciarra, G., Turci, R., and Bettinelli, M., Inductively coupled plasma mass spectrometric determination of molybdenum in urine, Rapid Communications in Mass Spectrometry, 2002, 16, 1313-1319.

Molybdenum concentration was analyzed in 24-hour urinary specimens (n = 193) to evaluate the range in pediatric patients in 20 children aged 0.4 to 9.3 (mean 2.3) years.The molybdenum concentration in 24 hour specimens was 4.0 (0-123) microg Mo/l.

Sievers, E., Schleyerbach, U., and Schaub, J., Molybdenum in infancy: Methodical investigation of urinary excretion, Journal of Trace Elements in Medicine and Biology, 2001, 15, 149-154.

Uric acid

The effect of molybdenoenzymes on atherosclerotic hyperuricaemic patients [uric acid]

In the present work Fourier transform infrared spectroscopy (FT-IR) was used to study the mechanism of calcification and plaque formation in carotid arteries in hyperuricaemic patients.

From the changes of the intensity and shape of the characteristic bands of the spectra of hyperuricaemic patients in comparison with corresponding spectra of normal patients it is suggested that the tissues change their flexibility and permeability due to peroxidation of lipids and phospholipids.

SEM (Scanning Electron Microscope) analysis showed that the carotid atheromatic plaques of the hyperuricaemic patients are rich in molybdenum.

This finding suggests that the molybdenum enzymes react with superoxide anions (O2) leading to molybdenum release and that xanthine oxidase (XO), a molybdenum-iron sulfur flavoprotein, cannot normalize the uric acid of the patients.

Mamarelis, I., Pissaridi, K., Dritsa, V., Koutoulakis, E., Chr, K., Kotileas, P., Tsiliggiris, V., Tzilalis, V., Xaplanteris, P., Lazaridis, K., and Anastassopoulou, J., The effect of molybdenoenzymes on atherosclerotic hyperuricaemic patients, Coronary Artery Disease: 2011 Update: from Prevention to Intervention, 2011, 83-89.

[Atherosclerosis (hardening of the arteries) occurs when fat, cholesterol, and other substances build up in the walls of arteries and form hard structures called plaques.

Hyperuricemia is a level of uric acid in blood that is abnormally high. In humans, the upper end of the normal range is 360 µmol/L (6 mg/dL) for women and 400 µmol/L (6.8 mg/dL) for men.]

Molybdenum in urinary calculi

Metals concentrations were determined in 110 urinary calculi samples from hospital patients in Jordan using X-ray fluorescence (XRF) and atomic absorption spectroscopy (AAS). Twenty-one calculi were pure calcium oxalate (CaOax), 29 were mixed calcium oxalate/uric acid, 23 were mixed calcium oxalate/phosphate (apatite), 25 were phosphate calculi (apatite/struvite), five were mixed calcium oxalate monohydrate/struvite, four were urate calculi (mixed ammonium acid urate/sodium acid urate) and three were pure cystine calculi. Mean metal concentrations were: Ca 48.18, Na 1.56, K 0.9, Mg 3.08, Fe 1.17, Al 0.49, Zn 0.7, Cu 0.19, Mn 0.029, P 10.35, S 1.88, Sr 0.306, Mo 0.2, Cr 0.146, Co 0.05, Ni 0.014 %.

It is noteworthy that the concentration of molybdenum in the urate and cystine calculi (0.65, 0.58 wt-%) is ten-fold greater than the concentration in the other calculi, a selectivity effect not found for the other metals and reflecting possibly the involvement of molybdenum in urate production via the molybdoenzyme xanthine oxidase.

Abboud, I. A., Concentration effect of trace metals in Jordanian patients of urinary calculi, Environmental Geochemistry and Health, 2008, 30, 11-20.

Sources of molybdenum uptake by humans

Molybdenum daily intake by humans in various countries
GroupingOriginDaily Intake /microg
Young female New Zealand 48 - 96
Child Russia (USSR) 156 - 161
Adult Russia (USSR) 329 - 376/ 200 - 500
General USA 210 - 460
General UK 128 ± 34
General Belgium 87 ± 11 mu g/day

Anke, M., Groppel, B., and Grun M., Essentiality, Toxicity, Requirement and Supply of Molybdenum in Humans and Animals , 1985, in: Mills, C. T., Bremner, I., and Chesters, J. K. (ed.), Trace Elements in Man and Animals, 154. C.A.B. Farnham Royal, London.
Van Cauwenbergh, R., Hendrix, P., Robberecht, H., Deelstra, H. Daily dietary molybdenum intake in Belgium using duplicate portion sampling. Zeitschrift Fur Lebensmittel-Untersuchung Und-Forschung A-Food Research And Technology,1997, 205, 1-41.

Daily Molybdenum Intake and Excretion Rates in Adults

Daily Molybdenum Intake and Excretion Rates in Adults
 Intake /microgExcretion /microg
Food 335  
Drinking water 2.8  
Air <1.0  
Total 338  
Urine   190
Feces   125
Perspiration   20
Total   335

Lever, J., and Bibr., Effects of Molybdenum on the Organism (A Review) , 1986. Dietary sources of molybdenum

Animal products, with the exception of the liver, are usually low in molybdenum. An extensive listing of the molybdenum content of different foods has been published [Koivistoninen, 1980]. Bovine and human liver contains about 3 ppm which is relatively high compared to other trace metals [Ward, 1987; Wennig and Kirsch, 1988]. It has been estimated that in England an adult diet contained 128 ± 34 mg of molybdenum per day [Friberg and Lener, 1986]. Papadopolou and Hadzistelios (1988), found 400-800 ng Mo/g dry weight in marine plankton, mussels and fish but no indication for food chain biomagnification. The rates of absorption of molybdenum from the diet are inversely related to dietary levels of inorganic sulfate. Of the various molybdenum compounds found in herbage only molybdenum disulfide appears to be poorly absorbed from the intestines of animals. The biological half-life of molybdenum in mammals is comparatively short, ranging from a matter of hours to several days [Friberg and Lener, 1986].

CG1H. Documentation of the Threshold Limit Values and Biological Exposure Indices 6th ed Vol. IL Cincinnati, Ohio: American Conference of Governmental and Industrial Hygienists. Inc.,
Koivistoninen, P., Mineral Element Composition of Finnish Foods. Acta Agric. Scand. (Suppl. 22) , 1980.
Ward, G. M., Progress Report of' the Molybdenum Project, University of Colorado, 1974, 179.
Wennig, R., and Kirsch, N., in Handbook on Toxicity of Inorganic Compounds, Seiler, H. G., Sigel, H., and Sigel, E., eds., Marcel Dekker, New York, 1988, 437.
Papadopolou, C. and Hadzistelios, I., Radiochemical Determination of Molybdenum in Marine Organisms from the Aegean Sea. Proceedings 3rd International Conference on Environmental Pollutants, Venice, 1988,70. CEP Consultants Ltd., Edinburgh.
Friberg, L. and Lener, J., in Handbook of Toxicology of Metals. Friberg L. et al., eds., 2nd Ed.,Elsevier Science Publishers, Amsterdam, 1986, II, 446.

Among plants, legumes (peas and beans) are relatively rich in and are good dietary sources of molybdenum. Cereal grains contain less molybdenum and fruits, berries, and most root and stem vegetables only minute traces. Among animal tissues, liver, kidney and spleen are relatively rich in molybdenum and are good dietary sources. Cows' milk has a relatively high molybdenum content (ca 50 microg/l, cf. river water ca 1 microg/l). Various vitamin and mineral supplements contain trace amounts of molybdenum although it is generally believed that the average diet provides adequate molybdenum for human beings. The average daily requirements of molybdenum for human beings are given. [Schroeder et al., 1970].

Schroeder, H. A., Balassa, J. J. and Tipton, I. H., J. Chronic Diseases, 1970, 23, 481.

Dietary exposure to Molybdenum

Determined by Inductively Coupled Plasma-Mass Spectrometry. Molybdenum limit of detection was 0.003 mg/kg fresh weight. Molybdenum concentrations (mg/kg fresh weight) in most foodstuffs were below 0.2. Exceptions with higher levels were offal (1.2), canned vegetables (0.31), nuts (0.96). The dietary exposure to Mo estimated from typical diets was in mg/day for the total population 0.11, for adult consumers 0.12 mean and 0.21 upper range.

Ysart, G., Miller, P., Crews, H., Robb, P., Baxter, M., DeLArgy, C., Lofthouse, S., Sargent, C., Harrison, N.,Dietary exposure estimates of 30 elements from the UK TotalDiet Study, Food Additives And Contaminants,1999, 16, 9,391-403.

Molybdenum Concentrations in Selected Foods
FoodCountriesConcentration /microg kg-1
Milk UK [1] 25
  USA [2] 38 - 48
  Germany [3] 29
  processed [4] 50
  powdered [4] 40
Potatoes Canada [5,6] 20 - 180
  USA [7,6] 30
  Singapore [16] 31 ppb
Cauliflower Switzerland [9,6] 2260
Cauliflower Czechoslovakia[8,6] 1150
Cauliflower [17]   winter170,summer 230microgMo/g wet digested
Beans Germany [10,6] 1000
  Russia [11,6] 6030
  USA [7,6] 4800
  Czechoslovakia [8,6] 1188
Wheats India [12,13,6] 490, 179-222
  Germany [10,6] 230 - 400
  Singapore [16] 510 ppb
corn British Columbia  
  Lower Fraser Valley [14] 100 - 2000
turnip root British Columbia  
  Lower Fraser Valley[14] 200 - 1000
carrot root British Columbia  
  Lower Fraser Valley[14] 100 - 500
lettuce British Columbia  
  Lower Fraser Valley[14] 100 - 200
spinach NIST Standard reference material [15] 0.43050.12 mg/kg
cucumber Singapore [16] 52 ppb
cabbage Singapore [16] 74 ppb
tea Singapore [16] 210 ppb
tomato Singapore [16] 38 ppb

[1] Stanton, R. E., Hardwick, A. J., Analyst, 1968, 93, 1
[2] Ward, G. M., Progress Report of' the Molybdenum Project, University of Colorado, 1974, 179.
[3] Kirchgessner, M., Z. Tierernahr. Futtermittelkunde, 1957, 12, 156.
[4] Koivistoninen, P., Mineral Element Composition of Finnish Foods. Acta Agric. Scand. (Suppl. 22) , 1980.
[5] Warren, H . V., Delavault, R. E., Fletcher, K. W., Geology Environ. Contr. Bull., 1971, 6, 34.
[6] Anke, M., Groppel, B., and Grun M., Essentiality, Toxicity, Requirement and Supply of Molybdenum in Humans and Animals , 1985, in: Mills, C. T., Bremner, I., and Chesters, J. K. (eds.), Trace Elements in Man and Animals, 154. C.A.B. Farnham Royal, London.( From J. Lener and B. Bibr: Effects of Molybdenum on the Organism, J. Hygiene, Epidem., Microbiol. and Immunol., 1984, 28, 405.)
[7] Schroeder, H. A ., Balassa, J. J., Tipton, I. H., J. Chron. Dis., 1970, 23, 481.
[8] Hlavsova D., Turek, B., Waldman, J.,-Tucek, J., Sbornik Cs. chemicke spolecnosti, Praha, 1972, 45.
[9] Boway, E., Rod, P., citovano podle Schlettwein-Gsell, D., Mommsen-Straub, S. (117).
[10] Schall, H., Schall, H., Nahrungsmitteltabelle, 18 Aufl., Barth Leipzig, 1973.
[11] Los, L. J., Pjatnickaja, L. K., Samsonova, A. S., Vop. Pitan., 1971, 30, 82.
[12] Reddy, G. R., Ind. J. Agr. Sci., 1964, 34, 219.
[13] Lupea, V., Vranceanu, C., Waltraut, M., citovano podle Schlettwein-Gsell, D., Mommsen-Straub, S. (117).
[14] Depieri, L.A., Buckley, W.T., Kowalenko, C.G., Micronutrient Concentrations Of Commercially Grown Vegetables And Of Soils In The Lower Fraser Valley Of British-Columbia, Canadian Journal Of Soil Science, 1996, 76, 173-182.
[15] Zeisler, R., Becker D.A., Gills T.E., Certifying the chemical composition of a biological material - a case study, Fresenius J. Anal. Chem., 1995, 352, 111 - 115.
[16] Gao, Z.Q., Siow, K.S., Catalytic-Adsorptive Stripping Voltammetric Determination Of Molybdenum In Plant Foodstuffs, Talanta,1996, 43, 719-726.
[17] Somer, G. and Unal, O., A new and direct method for the trace element determination in cauliflower by differential pulse polarography, Talanta, 2004, 62, 323-328.

Soybean flour

The total concentrations of Na, Mg, P, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Se and Mo in soybean flour and in extract of soybeanflour were determined by ICP - AES and ICP - MS. The soybean flour extract wassubmitted to fractionation by size exclusion chromatography ona Fractogel EMD Bio SEC (S) column with 0.2 mol/L Tris-HNO3buffer pH 7.5. Molybdenum was mostly found in a low- molecular fraction (2-3 kDa).

Fingerova, H., Koplik, R., Study of minerals and trace element species in soybean flour, Fresenius Journal Of Analytical Chemistry, 1999, 363, 5- 6, 545-549.

White wine

The average values for molybdenum content in white wines are within the range1.77x10-7-1.83 x 10-7 mol l-1.

Bejan, D., Kinetic-catalytic-spectrophotometric determination of low concentrations of molybdenum in white wines, Analytica Chimica Acta, 1999, 390, 1-3, 255-259.

Baby food

The preparation of the recently released Standard Reference Material (SRM) 2383 Baby Food Composite and the process used for value assignment of nutrient concentrations are reported. SRM 2383 can be used as a control material when assigning values to in-house control materials and when validating analytical methods for measuring proximates, vitamins, and minerals in baby food and similar matrixes. The SRM was prepared as a commercial baby food would be prepared, with the same ingredients. Molybdenum determined by ICP MS was 0.065 mg/kg.

Sharpless, K.E., Gill, L.M., Margolis, S.A., Wise, S.A., Elkins, E., Preparation of Standard Reference Material 2383 (Baby Food Composite) and use of an interlaboratory comparison exercise for value assignment of its nutrient concentrations, Journal Of Aoac International, 1999, 82, 2, 276-287.

Molybdenum in medical foods
Mo0.07-2.3 microu g/g
relative standard deviation 4.8% (n = 5)
detection limits 0.67 nanog/mL

Phifer, E.C. Determination Of Chromium And Molybdenum In Medical Foods By Graphite-Furnace Atomic-Absorption Spectrophotometry, Journal Of AOAC International, 1995, 78, 1497-1501.

Molybdenum in foodstuffs

Market baskets containing sixty food items included in the average Swedish diet were purchased from three shops in four major Swedish cities during autumn 1987. Food items were selected on the basis of food-balance-sheet data. Freeze-dried homogenates representative of each city were analysed for twelve essential or toxic mineral elements. The energy content of the market baskets (11.5 MJ) corresponded to the reference value for male adults. The molybdenum content was 150 mug, within the safe and adequate intake values given in the US recommended dietary allowance (Food and Nutrition Board, National Research Council, 1989).

Becker, W. And Kumpulainen, J., Contents Of Essential And Toxic Mineral Elements In Swedish Market-Basket Diets In 1987, British Journal of Nutrition, 1991, 66, 151-160.

Molybdenum in rice

Dietary intake of minerals and trace elements in rice on the Jamaican market

Twenty-five rice brands, available on the Jamaican market, and a local field trial sample were collected and analyzed for 36 essential, non-essential and toxic elements using four techniques: flame atomic absorption spectrophotometry (F-MS), inductively coupled plasma optical emission spectrometry (ICP-OES), instrumental neutron activation analysis (INAA), and total reflection X-ray fluorescence (TXRF). The mean values for both white and brown rice respectively for calcium (127 mg/kg; 104 mg/kg), chromium (0.08 mg/kg; 0.157 mg/kg), copper (1.65 mg/kg; 2.96 mg/kg), iron (22.3 mg/kg; 20.1 mg/kg), magnesium (371 mg/kg; 1205 mg/kg), manganese (10.5 mg/kg; 26.5 mg/kg), molybdenum (0.790 mg/kg; 0.770 mg/kg), phosphorus (1203 mg/kg; 3361 mg/kg), potassium (913 mg/kg; 2157 mg/kg). selenium (0.108 mg/kg; 0.131 mg/kg), sodium (6.00 mg/kg; 15.1 mg/kg), sulfur (1131 mg/kg; 1291 mg/kg) and zinc (15.6 mg/kg; 20.2 mg/kg) were used to calculate intake values. The percentage contribution to Provisional Tolerable Weekly Intakes were also estimated for the toxic elements aluminum (6.6-17.9%), arsenic (7.8-10.2%), cadmium (5.1-9.0%) and mercury (3.2-12.0%) with ranges dependent on white or brown rice consumption and gender. It was concluded that, for most essential elements, rice does not significantly contribute to mineral nutrition. The local field trial sample yielded encouraging results in terms of uptake of toxic elements. (C) 2012 Elsevier Inc. All rights reserved

Antoine, Johann M. R., Fung, Leslie A. H., Grant, Charles N., Dennis, Haile T., and Lalor, Gerald C., Dietary intake of minerals and trace elements in rice on the Jamaican market, Journal of Food Composition and Analysis, 2012, 26, 111-121.

Molybdenum in a dietetic preparation

Iron and molybdenum in a dietetic pharmaceutical preparation (multivitamin-multimineral preparation, Alcala Farma S.L., Spain) have been determined by flame atomic absorption spectrometry (FAAS) after dry ashing at 600 degreesC. The interest of the paper is the precision of Mo determination.

For molybdenum

Concentration in the preparation ca 0.08 mgMo/g.

Linearity of response was verified for concentrations 1.00 to 6.00 mg/ l of molybdenum.

Precision of the methods, performed under conditions of repeatability and reproducibility, gave relative standard deviations of 1.0 and 6.5%, respectively.

Mean recoveries determined after spiking dietetic preparation placebos 95.2 to 102.9%

The limit of detection 129 mug/l.

Quantification limits were 433 mug/l

Day-to-day and analyst-to-analyst variability was 4.5% for molybdenum.

Results show the suitability of the method for measurement of iron and molybdenum in a complex matrix sample such as a dietetic pharmaceutical preparation.

Canfranc, E., Abarca, A., Sierra, I., and Marina, M. L., Determination of iron and molybdenum in a dietetic preparation by flame AAS after dry ashing, Journal of Pharmaceutical and Biomedical Analysis, 2001, 25, 103-108.

Mo dietary uptake

Dietary intakes of 25 pairs of Japanese children and their parents of 12 toxic and essential trace elements using 7-day duplicate diet composites were determined. Intake of molybdenum (children 103, adults 131 mg/day were close to the recommended values.

Aung, N. N., Yoshinaga, J., and Takahashi, J. I., Dietary intake of toxic and essential trace elements by the children and parents living in Tokyo Metropolitan Area, Japan, Food Additives and Contaminants, 2006, 23, 883-894.

Compare Mo retention in animals (see also Experimental Toxicity and Physiology)

Mo release from joint replacements

No significant differences were observed in mean serum and urinary levels of Mn, Mo and Ni between patients who had undergone arthroplasty [joint replacement, e.g. knee, hip] and control subjects.

Iavicoli, I., Gianluca, F., Alessandrelli, M., Rafaella, C., De Santis, V., Salvatori, S., Alimonti, A., and Carelli, G., The release of metals from metal-on-metal surface arthroplasty of the hip, Journal of Trace Elements in Medicine and Biology, 2006, 20, 25-31.

The concentrations of 14 trace elements in blood plasma are reported for 158 patients in 3 dialysis surgeries having chronic kidney failure. Molybdenum concentrations/microg l-1 were:

Normal group: minimum 0.27 median 0.66 maximum 1.7

Reference: lower limit 0.3 upper limit 1.2

Dialysis patients: 0.6 3.2 7.7

Keller, T., Gehring, L., Loser, T., Trace element disorders in patients with chronic kidney failure during dialysis, Nieren-Und Hochdruckkrankheiten, 1998, 27,12,522-532.

The role of blood and blood components in the process of molybdenum metabolism is not as yet clear. Molybdenum concentrations in blood and blood serum have been determined under both normal and pathological conditions. The serum molybdenum concentration in blood donors was 1.8 ng/g, in hospital personnel 3.4 ng/g and in patients with degenerative diseases 1.2 ng/g. Patients treated for specific processes were found to have 7.2 ± 0.3 ng/g of molybdenum in their whole blood [Butt et al.,1964]. The fate of 99Mo in human subjects has also been studied [Rosoff and Spencer, 1964]. A single tracer dose of 50-100 microCi was injected intravenously. After injection blood levels of the isotope fell rapidly (from 5% to 0-5% within 1 to 8 h). The extent to which molybdenum accumulates in persons exposed to low daily concentrations of molybdenum is not known but if the animal experiments are taken as a guide it is likely that the rate of accumulation of molybdenum is small.

Butt, E. M., Nusbaum, R. E., Gilmour, T. C. and Didio, S. L., Arch. Environ. Health, 1964, 8, 52.
Rosoff, B. and Spencer, H., Nature, 1964, 202, 410.

Skin lesions from a metal implant containing molybdenum ― alleged histiocytosis associated with molybdenum

A unique case of intralymphatic histiocytosis with granuloma formation associated with orthopaedic metal implants is reported. Asymptomatic reddish-brown nodules were observed on the left knee of a seventy-five year old man; an orthopaedic metal implant had been inserted in the knee for a knee joint disorder. Histopathological examination revealed typical features of mixed cell granuloma with many dilated lymphatics that contained many histiocytes from the upper dermis to subcutaneous fat tissue. Biopsy specimens were analysed qualitatively by energy-dispersive X-ray spectroscopy and were positive for molybdenum, one of the constituents of the metal implant. It is suggested that the synovial fluid containing molybdenum had drained into the skin lesion from the synovial cavity of the left knee. The lesions disappeared following drainage.

[Intralymphatic: situated within or introduced into a lymphatic vessel

Histiocytosis: an abnormal increase in the number of certain immune cells, called histiocyte cells.

Histiocyte: A macrophage (cell which ingests particulate materials) found within the tissues.

Granuloma: a localised accumulation of macrophages around the site of some continuing stimulus, e.g. injury, inflammation or infection, having their cell membranes fused together so as to form multinucleated giant cells.]

COMMENT. The case of intralymphatic histiocytosis associated with an orthopaedic metal implant reported in this paper is unique. Any significance to be attached to molybdenum in the biopsy specimens is not clear and is not discussed. There is, of course, no control.

Watanabe, T., Yamada, N., Yoshida, Y., and Yamamoto, O., Intralymphatic histiocytosis with granuloma formation associated with orthopaedic metal implants, British Journal of Dermatology, 2008, 158, 402-404.