Molybdenum in Human Health
Molybdenum uptake, absorption and excretion in humans
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.
|
|
Adequate intake (AI)/ microg/day |
Estimated average requirement (EAR) microg/day |
Recommended dietary allowance (RDA) microg/day |
Tolerable 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
| Intake /microg |
Excretion /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.
| Adequate intake (AI)/ microg/day |
Estimated average requirement (EAR) /microg/day |
Recommended dietary allowance (RDA) /microg/day |
Tolerable 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.
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.
| Age |
DRI 2001 RDA /microgMo/day |
Age |
DACH Reference value 2000 /microgMo/day |
Age |
Tolerable 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 |
k.A., no data
Gassmann, B., Dietary reference intakes, report 4: Trace elements, Ernahrungs-Umschau, 2001, 48, 148-152.
Molybdenum recommended intake for premature infants
| Status |
Recommended 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
| 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
| Location |
Retention |
| 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
| Status |
Recommended 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
| Subject |
1 |
2 |
3 |
4 |
| 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:
| microg/l |
microg/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.
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
| Grouping |
Origin |
Daily 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
| Intake /microg |
Excretion /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.
| Food |
Concentration /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.
| Mo |
0.07-2.3 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 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.
