PRODUCTS

SODIUM MOLYBDATE

Sodium molybdate, Na2MoO4, is useful as a source of molybdenum.[2] It is often found as the dihydrate, Na2MoO4·2H2O.
The molybdate(VI) anion is tetrahedral. Two sodium cations coordinate with every one anion.
Sodium Molybdate is a crystalline powder essential for the metabolism and development of plants and animals as a cofactor for enzymes.

SODIUM MOLYBDATE

CAS No. : 7631-95-0
EC No. : 231-551-7

Synonyms:
Disodium molybdate; Sodium molybdate dihydrate; Molybdic acid, disodium salt, dihydrate; molibden; Sodium molybdate; Disodium molybdate; 7631-95-0; Sodium molybdate(VI); Molybdate disodium; Natriummolybdat; sodium molybdenum oxide; Molybdic acid, disodium salt; Natriummolybdat [German]; Sodium molybdate (VAN); Sodium molybdate (Na2MoO4); EINECS 231-551-7; NSC 77389; sodium molybdate (anhydrous); Molybdic acid (H2MoO4) , disodium salt; Molybdate (MoO42-), disodium, (T-4)-; disodium;dioxido(dioxo)molybdenum; Molybdic acid sodium salt dihydrate; 13466-16-5; Molybdate (MoO42-), disodium, (beta-4)-; Sodium dimolybdate; Na2MoO4; Sodium Molybdate Anhydrous; MoNa2O4; Molybdic acid (H2MoO4), disodium salt; Molybdenum (as sodium); Anhydric sodium molybdate; disodium tetraoxomolybdate; sodium molybdate (anh.); Molybdic acid, sodium salt; EC 231-551-7; Sodium Molybdate, anhydrous; Sodium molybdate, >=98%; Ddisodium Molybdate Dihydrate; Sodium Molybdate, ACS Grade; Molybdate (MoO42-), sodium (1:2), (T-4)-; sodium dioxido(dioxo)molybdenum; Sodium Molybdate 35% Solution; Sodium Molybdate Solution 35%; CHEBI:75215; Sodium molybdate, LR, >=99.5%; AKOS015912969; DB14496; LS-91592; Sodium Molybdate Crystals, Technical Grade; FT-0701280; Sodium Molybdate Dihydrate (Technical Grade); C15455; Molybdic acid (H2MoO4), disodium salt (8CI); Q414518; Sodium molybdate, anhydrous, powder, -100 mesh particle size, 99.9% trace metals basis; Sodium molybdate (Compound); Molybdic acid sodium salt dihydrate; Sodium Molybdenum Oxide Dihydrate, Disodium molybdate dihydrate, Molybdic acid sodium salt dihydrate, Sodium molybdate(VI) dihydrate, Sodium dioxido(dioxo)molybdenum hydrate (2:1:2); Sodium Ammonium Trimolybdate Nanowires; Sodium Molybdate, Anhydrous; Sodium Phosphomolybdate Hydrate; Sodium Molybdate; Disodium molybdate; Sodium molybdate dihydrate; Molybdic acid, disodium salt, dihydrate; molibden; Sodium molybdate; Disodium molybdate; 7631-95-0; Sodium molybdate(VI); Molybdate disodium; Natriummolybdat; sodium molybdenum oxide; Molybdic acid, disodium salt; Natriummolybdat [German]; Sodium molybdate (VAN); Sodium molybdate (Na2MoO4); Ammonium Molybdate Solution; Barium Europium Calcium Molybdate; Copper Molybdate Sputtering Target; Ammonium Heptamolybdate; Ammonium Octamolybdate; Molybdenum; Disodium molybdate; disodium tetraoxomolybdate; Molybdic acid, disodium salt; Na2MoO4; Natriummolybdat Deutsch; sodium molybdate; sodium molybdate (anh.); Sodium molybdate(VI); sodium orthomolybdate; Sodium molybdate(VI) dihydrate, 99+%, ACROS Organics; disodium; dioxido(dioxo)molybdenum; dihydrate; sodium molybdate dihydrate; sodium molybdate vi dihydrate; disodium molybdate dihydrate; na2moo4.2h2o; disodium dihydrate molybdate; molybdic acid sodium salt dihydrate; molybdic acid; disodium salt; dihydrate; sodium molybdate 2 hydrate; dipotassium dihydrate molybdate

Sodium Molybdate

History
Sodium molybdate was first synthesized by the method of hydration.[4] A more convenient synthesis is done by dissolving MoO3 in sodium hydroxide at 50–70 °C and crystallizing the filtered product.[3] The anhydrous salt is prepared by heating to 100 °C.
MoO3 + 2NaOH + H2O → Na2MoO4·2H2O

Uses
The agriculture industry uses 1 million pounds per year as a fertilizer. In particular, its use has been suggested for treatment of whiptail in broccoli and cauliflower in molybdenum-deficient soils.[5][6] However, care must be taken because at a level of 0.3 ppm sodium molybdate can cause copper deficiencies in animals, particularly cattle.[3]
It is used in industry for corrosion inhibition, as it is a non-oxidizing anodic inhibitor.[3] The addition of sodium molybdate significantly reduces the nitrite requirement of fluids inhibited with nitrite-amine, and improves the corrosion protection of carboxylate salt fluids.[7]
In industrial water treatment applications where galvanic corrosion is a potential due to bimetallic construction, the application of sodium molybdate is preferred over sodium nitrite. Sodium molybdate has the advantage in that the dosing of lower ppm's of molybdate allow for lower conductivity of the circulating water. Sodium molybdate at levels of 50-100 ppm offer the same levels of corrosion inhibition that sodium nitrite at levels of 800+ ppm. By utilizing lower concentrations of sodium molybdate, conductivity is kept at a minimum and thus galvanic corrosion potentials are decreased.

Reactions
When reacted with sodium borohydride, molybdenum is reduced to lower valent molybdenum(IV) oxide:
Na2MoO4 + NaBH4 + 2H2O → NaBO2 + MoO2 + 2NaOH + 3H2
Sodium molybdate reacts with the acids of dithiophosphates:
Na2MoO4 + (R = Me, Et)(RO)2PS2H → [MoO2(S2P(OR)2)2]
which further reacts to form [MoO3(S2P(OR)2)4].

Compound Formula   H4Na2MoO6
Molecular Weight   241.95
Appearance   White powder or crystals
Melting Point   100 °C
Boiling Point   N/A
Density   2.37 g/cm3
Solubility in H2O   N/A
Exact Mass   243.885735
Monoisotopic Mass   243.885735

Chemical Identifiers
Linear Formula   Na2MoO4 • 2H2O
MDL Number   MFCD00149170
EC No.   231-551-7
Pubchem CID   16211258
IUPAC Name   disodium; dioxido(dioxo)molybdenum; dihydrate
SMILES   [Na+].[Na+]. O.O.[O-][Mo] ([O-])(=O)=O
InchI Identifier   InChI=1S/Mo.2Na.2H2O.4O/h;;;2*1H2;;;;/q;2*+1;;;;;2*-1
InchI Key   FDEIWTXVNPKYDL-UHFFFAOYSA-N

Safety
Sodium molybdate is incompatible with alkali metals, most common metals and oxidizing agents. It will explode on contact with molten magnesium. It will violently react with interhalogens (e.g., bromine pentafluoride; chlorine trifluoride). Its reaction with hot sodium, potassium or lithium is incandescent.
It is a molybdenum transition metal and in its pure form it is silvery white in color and very hard. Its melting temperature is quite high. Further hardening of the steel can be achieved by adding a small amount. Molybdenum is also important in the nutrition of plants and is involved in some enzymes.

Swedish chemist Carl Wilhelm Scheele showed in 1778 that the mineral (molybdenite), which was previously thought to be a lead ore or graphite, was a sulfur compound of an unknown metal. Swedish chemist Peter Jacob Hjelm also separated molybdenum into metal in 1782 and named it after the Greek word molybdos, which means "like lead".
Although molybdenum is found in minerals such as wulfenite (PbMoO4) or powellite (CaMoO4), the main commercial source of molybdenum is molybdenite (MoS2). Molybdenum can also be obtained by direct mining and as a byproduct during copper mining. Molybdenum is found in its ores in amounts varying from 0.01% to 0.5%. About half of the world's molybdenum mining is carried out in the USA (Phelps Dodge Corporation).
Molybdenum, which is similar to chromium and wolfram in terms of chemical properties; It has superior properties such as high melting and boiling point, high heat resistance, high thermal conductivity and low thermal expansion. Molybdenum melts at 2623 ° C. With this feature, it takes the sixth place among metals. Molybdenum boiling at 4639 ° C is not affected by air in cold, oxidized in incandescent state, affected by nitric and sulfuric acids, decomposes water vapor at high temperatures. The density of molybdenum is 10.28 gr / cm3.

Usage areas
The agricultural industry uses up to £ 1 million a year of fertilizer. In particular, it has been suggested to be used for processing broccoli and cauliflower seeds in molybdenum deficient soils.
However, caution should be exercised as sodium molybdate at a level of 0.3 ppm can cause copper deficiencies in animals, especially cattle.
It is used in industry for corrosion prevention because it is a non-oxidizing anodic inhibitor.
The addition of sodium molybdate significantly reduces the nitrite requirement of nitrite-amine inhibited liquids and improves the corrosion protection of carboxylate salt fluids.
In industrial water treatment applications where galvanic corrosion is potential due to the bimetal structure, sodium molybdate application is preferred over sodium nitrite.
Sodium molybdate has the advantage that lower ppm molybdate dosing has lower conductivity of circulating water. Sodium molybdate at 50-100 ppm levels offers the same levels of corrosion inhibition as sodium nitrite at 800+ ppm levels.
By using lower concentrations of sodium molybdate, conductivity is kept to a minimum, thus reducing galvanic corrosion potential

Sodium Molybdate Dihydrate is generally immediately available in most volumes. Hydrate or anhydrous forms may be purchased. High purity, submicron and nanopowder forms may be considered. American Elements produces to many standard grades when applicable, including Mil Spec (military grade); ACS, Reagent and Technical Grade; Food, Agricultural and Pharmaceutical Grade; Optical Grade, USP and EP/BP (European Pharmacopoeia/British Pharmacopoeia) and follows applicable ASTM testing standards. Typical and custom packaging is available. Additional technical, research and safety (MSDS) information is available as is a Reference Calculator for converting relevant units of measurement.

WHAT IS SODIUM MOLYBDATE?
There are two main forms of Sodium Molybdate. Sodium Molybdate, Dihydrate is a crystalline powder. It loses its water of crystallization at 100 degrees Celsius. It is known to be less toxic than the other corresponding compounds of group 6B elements in the periodic table. Sodium Molybdate, Dihydrate is used in the manufacturing of inorganic and organic pigments, as a corrosion inhibitor, as a bath additive for finishing metals finishing, as a reagent for alkaloids, and as an essential micronutrient for plants and animals.

Sodium Molybdate, Anhydrous is a small, lustrous, crystalline plate. It has the melting point of 687 degrees Celsius and a density of 3.28 (18C). It is soluble in water and also noncombustible. It can be used for reagent in analytical chemistry, paint pigment, production of molybdated toners and lakes, metal finishing, brightening agent for zinc plating, corrosion inhibitor, catalyst in dye and pigment production, additive for fertilizers and feeds, and micronutrient.

WHY THE AGRICULTURE INDUSTRY USES SODIUM MOLYBDATE
Sodium Molybdate uses cover a wide range of fields, including manufacturing, metalwork, printing, and more. But the impact it can have on plants and animals has brought it into the forefront of use for the agriculture industry, to the tune of more than 1 million pounds of sodium molybdate fertilizer used per year.

The basic chemistry of a molybdate, such as sodium molybdate, contains the element molybdenum in its highest oxidation state, which in turn helps contribute to a high solubility of the chemical in water, a benefit in fertilizer application. This characteristic, when combined with sodium molybdate’s use as a delivery vessel for essential micronutrients (such as molybdenum) in plants, serves as another key reason for the choice of sodium molybdate fertilizer over other types of fertilizers used in agriculture.
Another touchpoint for this usage ties back to the hydroponic nutrient practice that is growing in popularity. Hydroponics is an agricultural method in which plants are grown without soil. Instead, they receive their essential micronutrients through a water solvent, a practice that has shown growth rates almost 50 percent faster than traditional soil-grown plants, in addition to a higher yield from hydroponic plants.

Sodium molybdate has seen a particularly strong uptick in usage among farmers of leguminous plants, such as alfalfa, peas, beans, lentils and peanuts. Included in fertilizer, it provides these plants with enhanced uptake of the essential nitrogen element, while also allowing for efficient fixing of atmospheric nitrogen found in the atmosphere by bacteria in the legumes. These bacteria convert the nitrogen into ammonia to synthesize amino acids within the plant.
Overall, the use of sodium molybdate in the agricultural industry can be summarized in that it is one of the few chemicals that can provide essential micronutrients and help drive plant function in a form that is both efficient and effective. Efficiency is shown not only by the relatively small amounts needed to make an impact on the treated plants, but also in the ability to administer the chemical in easily-absorbed water-based formats.

Use of Sodium Molybdate Dihydrate as an Efficient Heterogeneous Catalyst for the Synthesis of Benzopyranopyrimidine Derivatives
Sodium molybdate dihydrate (Na2MoO4.2H2O) has been investigated as a heterogeneous catalyst for the one-pot pseudo–four-component synthesis of the benzopyranopyrimidine derivatives. This efficient and facile technique avoids the use of difficult workup and harsh reaction conditions.

SODIUM MOLYBDATE
Sodium Molybdate is a free flowing soluble crystalline fertiliser and is used to supply the trace element molybdenum to crops and livestock in various situations. Sodium Molybdate is only required in very small quantities to satisfy annual plant requirements. Sodium Molybdate is suitable for foliar or fertigation application on a wide range of horticultural and broad acre crops and pastures.
SODIUM MOLYBDATE BENEFITS
• Supplies the essential trace element molybdenum to crops and livestock
• Foliar applied to crops and pastures grown on acid soils where plant availability is low
• Essential for conversion of nitrates in leaves to amino acids and proteins
• Suitable for foliar or fertigation
• Ideal for brassica, beans, peas, grapes, cucurbits, canola, clover and other crops and pastures susceptible to molybdenum deficiency.

Application
Sodium Molybdate can be used as a foliar or fertigation application in a regular nutrition program for applicable crops and pastures. Multiple applications may be required if leaf analyses reveal ongoing deficiency.
Note: Molybdenum can be toxic when levels become too high. One spray per crop is generally sufficient, except where deficiency is noted. Susceptible crops such as brassicas and cucurbits may require two sprays three weeks apart

Molybdate Stabilization
It is well known that sodium molybdate forms stable complexes with thiols (Kay and Mitchell, 1968; Kaul et al., 1987). Ever since Pratt described the ability of molybdate to stabilize the steroid binding activity of receptors, and to block activation (or transformation) (Leach et al., 1979), it has been suspected that molybdate exerted its effects by interacting with cysteines of the receptor. A series of indirect experiments led to the postulate that the sequence of 644–671, and especially cysteines 656 and 661, were required for molybdate stabilization (Dalman et al., 1991a). Experiments with receptor fragments of wild-type and mutant receptors have supported the involvement of this region. However, they have also ruled out the involvement of Cys-656 and 661 in any of molybdate’s effects (Modarress et al., 1994) (see Section III,E,4).

Chemicals
Cobalt thiocyanate, cobalt acetate dihydrate, glacial acetic acid, isopropylamine, acetaldehyde, ammonium vanadate, formaldehyde, para-dimethylaminobenzaldehyde, ferric chloride, vanillin, sodium molybdate, selenius acid, copper sulfate pentahydrate, sodium nitroprusside, 2-chloroacetophenone, and sodium carbonate were purchased from Sigma-Aldrich Chemical (St. Louis, MO, USA). Methanol, hexane, and chloroform were obtained from Burdick and Jackson (Muskegon, MI, USA). Hydrochloric acid, sulfuric acid, nitric acid, and pyridine were purchased from Mallinckrodt Baker, (Paris, KY, USA). Ethanol was obtained from Quantum Chemical (Tuscola, IL, USA). The drugs were purchased in powder form from Sigma-Aldrich Chemical (St. Louis, MO, USA), Alltech-Applied Science (State College, PA, USA) or Research Triangle Institute (RTI, NC, USA).

Animal
Water-insoluble molybdenite (MoS2) is practically nontoxic; rats dosed with up to 500 mg molybdenite daily for 44 days exhibited no adverse effects. In contrast, animals dosed subchronically with water-soluble molybdenum compounds exhibited gastrointestinal disturbances, growth retardation, anemia, hypothyroidism, bone and joint deformities, liver and kidney abnormalities, and death. Fifty percent mortality was reported in rats maintained for 40 days on molybdenum-enhanced diets containing 125 mg Mo kg−1 (as molybdenum trioxide, MoO3), 100 mg Mo kg−1 (as calcium molybdate, CaMoO4), or 333 mg Mo kg−1 (as ammonium molybdate, (NH4)2MoO4). A dietary level of 0.1% sodium molybdate (Na2MoO4·2H2O) for several weeks was lethal to rabbits. Growth retardation was observed in rats maintained on diets containing 0.04–0.12% molybdenum. Evidence that the toxic effects of molybdenum might be caused by a secondarily acquired copper deficiency was shown in a study where a significant reduction in growth occurred in rats after 11 weeks on a diet containing 20 ppm molybdenum and 5 ppm copper; whereas, growth was not affected by molybdenum dietary levels as high as 80 ppm when the dietary level of copper was increased to 20 ppm. Hypothyroidism, as evidenced by decreased levels of plasma thyroxin, was found in rabbits maintained on a diet containing 0.3% Mo (as sodium molybdate) for several weeks or longer.

Anemia, as well as anorexia, weight loss, alopecia, and bone deformities occurred in young rabbits maintained for 4–17 weeks on a diet containing 0.1% molybdenum (as sodium molybdate). Anemia was also observed in rats maintained on a diet containing 0.04% Mo (as sodium molybdate) for 5 weeks, in rabbits on a dietary level of 0.2% sodium molybdate for 5 weeks, and in chicks on a dietary level of 0.4% sodium molybdate for 4 weeks. Signs of anemia and marked erythroid hyperplasia of the bone marrow were observed in rabbits maintained for 11 days on a diet containing 0.4% sodium molybdate. Bone and connective tissue disorders observed in animals receiving dietary levels of molybdenum 0.04% for 4 weeks or longer included mandibular exostoses, joint deformities, detachment of tendons, epiphyseal line fractures, and epiphyseal plate widening.

Acute and Short-Term Toxicity
There is considerable variability in the toxicity of molybdenum, depending on the chemical form and the animal species. Generally, soluble compounds are more toxic than insoluble compounds. In animals, acutely toxic oral doses of molybdenum result in severe gastrointestinal irritation with diarrhea, coma, and death from cardiac failure. The rat oral lethal doses (LD50s) values are 188 mg kg−1 for molybdenum trioxide, and 680 mg kg−1 for ammonium molybdate. The LD50 for water-insoluble molybdentite (MoS2) is >500 mg kg−1 and exposures at this level for 44 days exhibited no adverse effects. Oral subchronic median LD50s for molybdenum oxide, calcium molybdate, and ammonium molybdate in rats were 125, 101, and 330 mg kg−1 day−1, respectively, with deaths occurring over a period of 8–232 days. Molybdenum compounds produce varying degrees of eye and skin irritation, with molybdenum trioxide producing eye and respiratory irritation. Rabbits exposed to dietary doses of ammonium molybdate at 0.025, 0.5, 5, and 50 mg kg−1 day−1 for 6 months resulted in liver changes that generated a NOAEL of 0.5 mg kg−1 day−1. Guinea pigs are a less-sensitive species after dietary exposure to sodium molybdate for 8 weeks yielded a LOAEL of 75 mg kg−1 day−1. Anemia, as well as anorexia, weight loss, alopecia, and bone deformities occurred in young rabbits maintained for 4–17 weeks on a diet containing 0.1% molybdenum (as sodium molybdate). Anemia was also observed in rats maintained on a diet containing 0.04% Mo (as sodium molybdate) for 5 weeks, in rabbits on a dietary level of 0.2% sodium molybdate for 5 weeks, and in chicks on a dietary level of 0.4% sodium molybdate for 4 weeks. Signs of anemia and marked erythroid hyperplasia of the bone marrow were observed in rabbits maintained for 11 days on a diet containing 0.4% sodium molybdate. Bone and connective tissue disorders observed in animals receiving dietary levels of molybdenum 0.04% for 4 weeks or longer included mandibular exostoses, joint deformities, detachment of tendons, epiphyseal line fractures, and epiphyseal plate widening.

Medium formulation
Chemostat glucose-limited synthetic minimal media contains (per liter) 0.1 g calcium chloride, 0.1 g sodium chloride, 0.5 g magnesium sulfate, 1 g potassium phosphate monobasic, 5 g ammonium sulfate, 500 μg boric acid, 40 μg copper sulfate, 100 μg potassium iodide, 200 μg ferric chloride, 400 μg manganese sulfate, 200 μg sodium molybdate, 400 μg zinc sulfate, 1 μg biotin, 200 μg calcium pantothenate, 1 μg folic acid, 1 mg inositol, 200 μg niacin, 100 μg p-aminobenzoic acid, 200 μg pyridoxine, 100 μg riboflavin, 200 μg thiamine, and 0.08% glucose.
Medium is prepared in 10 l quantities, mixed thoroughly, and filter sterilized into an autoclaved glass carboy. Carboy has an outlet port at bottom, leading to a small piece of tubing with a luer lock connector at the end. All entry and exit ports are covered with foil before autoclaving. Outflow tubing is sealed with a metal clamp before filling. Carboy is placed on a shelf above chemostat area.

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on safety and efficacy of sodium molybdate dihydrate for sheep, based on a dossier submitted for the re‐evaluation of the additive. The additive is currently authorised in the EU for all animal species as ‘Nutritional additive’ – ‘Compounds of trace elements’. Taking the optimal Cu:Mo ratio of 3–10, and the highest total copper level authorised in complete feeds for sheep (15 mg/kg), the FEEDAP Panel concluded that 2.5 mg total Mo/kg complete feed is safe for sheep. Considering (i) a safe intake of 0.6 mg Mo/day, (ii) the estimate average intake figure from food in Europe (generally less than 100 μg/day), (iii) the contribution of foods of animal origin to the total molybdenum intake (estimated to be up to 22 %), and (iv) that molybdenum would not accumulate in edible tissues/products of sheep fed molybdenum supplemented diets up to the upper safe level, the FEEDAP Panel concluded that the use of sodium molybdate as a additive in sheep at 2.5 mg total Mo/kg complete feed is safe for consumers. The additive under assessment feed poses no risk by inhalation to users; it is a skin and eye irritant, but it is not considered as a skin sensitiser. Sodium molybdate used up to 2.5 mg Mo/kg complete sheep feed poses no concerns for the safety for the environment. The FEEDAP Panel recognises that molybdenum does not need to be added to diets to cover the nutritional needs of molybdenum of sheep. Molybdenum supplementation in sheep feed is considered effective in order to guarantee an adequate balance with copper, when the Cu:Mo ratio in the diet is in the range 3–10.

Summary
Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on safety and efficacy of sodium molybdate dihydrate for sheep. The additive is currently authorised in the European Union (EU) under the element Molybdenum‐Mo (E7) for all animal species; the compound is included in the EU Register of Feed Additives under the category ‘Nutritional additives’ and the functional group ‘Compounds of trace elements’.

Molybdenum toxicity in farm animals is manifested as antagonism of absorption and/or biological activity of copper, and is greatly enhanced by high sulfur content in the diet. Ruminants, including sheep, are highly susceptible to molybdenum excess, which may induce a clinically severe copper deficiency (molybdenosis). Conversely, low molybdenum in the diet is expected to enhance copper toxicity, if the intake of copper is high. The FEEDAP Panel considered therefore not possible to establish an absolute figure for a dietary molybdenum concentration which is equally safe for sheep and effective in preventing copper toxicity. Considering that (i) the key parameter to ensure the safety of molybdenum supplementation is the optimal Cu:Mo ratio, which in sheep is in the range of 3–10 and (ii) the highest total copper level authorised in complete feeds for sheep is 15 mg/kg, the FEEDAP Panel concluded, that 2.5 mg total Mo/kg complete feed is safe for sheep.

Toxicokinetic data in laboratory rodents and farm animals (including sheep), however incomplete, uniformly indicate that molybdenum would not accumulate in edible tissues or products of sheep fed molybdenum supplemented diets up to the upper maximum level of 2.5 mg/kg. The FEEDAP Panel considered that the available data support an upper intake tolerable level (UL) of 0.01 mg/kg body weight (bw) for molybdenum based on the no observed adverse effect level (NOAEL) for female reproductive toxicity and developmental toxicity of 0.9 mg/kg bw per day and the application of a 100‐safety factor. The UL would result in a safe intake of 0.6 mg/day in a 60‐kg individual; this intake is largely higher than the estimate average intake figure from food in Europe (generally less than 100 μg/day). Molybdenum is ubiquitous in foods, surveys in the EU countries provide average intake figures generally lower than 100 μg/day, whereas offals (liver and kidney) are relatively rich sources of molybdenum, the contribution of foods of animal origin to the total molybdenum intake has been estimated to be up to 22%. Molybdenum would not accumulate in edible tissues or products of sheep fed molybdenum supplemented diets up to the upper maximum level of 2.5 mg/kg. Therefore, the FEEDAP Panel considered that the use of sodium molybdate as a feed additive in sheep at 2.5 mg Mo/kg complete feed is safe for consumers.

Molybdenum is a potential respiratory toxicant; the available data indicate that the use of the sodium molybdate under evaluation in animal nutrition poses no risk by inhalation to users. The additive is a skin and eye irritant, but it is not considered as a skin sensitiser.
The use of sodium molybdate as a feed additive in sheep up to maximum of 2.5 mg of Mo/kg complete feed poses no concerns for the safety for the environment.
The FEEDAP Panel recognises that molybdenum does not need to be added to diets to cover the nutritional needs of molybdenum of sheep. Molybdenum supplementation in sheep feed is considered effective in order to guarantee an adequate balance with copper, when the Cu:Mo ratio in the diet is in the range 3–10.

Additional information
The additive ‘Sodium molybdate’ had been authorised in the European Union (EU) under the element Molybdenum‐Mo (E7) for all animal species ‘Without a time limit’ (Council Directive 70/524/EEC concerning additives in feedingstuffs – List of authorised additives in feedingstuffs (2004/C 50/01). Following the provisions of Article 10(1) of Regulation (EC) No 1831/2003 the compound was included in the EU Register of Feed Additives under the category ‘Nutritional additives’ and the functional group ‘Compounds of trace elements’.
The Scientific Committee on Food (SCF) of the European Commission published in the year 2000 an opinion on the tolerable upper intake levels of molybdenum (European Commission, 2000). The EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS Panel) delivered an opinion on potassium molybdate as a source of molybdenum added for nutritional purposes to food supplements (EFSA, 2009). The EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA Panel) delivered an opinion on dietary reference values for molybdenum (EFSA NDA Panel, 2013).

According to Regulation (EC) no 1170/20092, Molybdenum is listed as mineral which may be used in the manufacture of food supplements (Annex I); the following molybdenum compounds are authorised for use in the manufacture of food supplements: ammonium molybdate (molybdenum (VI)), potassium molybdate (molybdenum (VI)) and sodium molybdate (molybdenum (VI)) (Annex II); the following molybdenum compounds are authorised as mineral substances which may be added to foods: ammonium molybdate (molybdenum (VI)) and sodium molybdate (molybdenum (VI)) (Annex III).
The following molybdenum compounds may be added for specific nutritional purposes in foods for particular nutritional uses (Commission Regulation (EC) No 953/2009)3: ammonium molybdate and sodium molybdate.
The following types of fertilisers containing molybdenum and described as ‘Fertilisers containing only one micro‐nutrient’ are listed in Annex I of Regulation (EC) No 2003/2003 of the European Parliament and of the Council4 as: (a) sodium molybdate (chemically obtained product containing sodium molybdate as its essential ingredient), (b) ammonium molybdate (chemically obtained product containing ammonium molybdate as its essential ingredient), (c) molybdenum‐based fertiliser Product obtained by mixing types (a) and (b)), and (d) molybdenum‐based fertiliser solution (product obtained by dissolving types ‘(a)’ and/or one of the type ‘(b)’ in water).

Effects on skin and eye
No original studies were provided by the applicant. The potential of sodium molybdate to elicit skin and ocular irritation or skin sensitization were briefly reviewed in (European Commission, 2000). When tested in rabbits, sodium molybdate (anhydrous form) elicited evident skin irritation for 24 h after application, albeit the skin lesions reversed within 72 . In an eye irritation test on rabbits, a 20% solution did not increase corneal irritation but caused evident conjunctival redness. Based on these findings, sodium molybdate is considered as a skin and eye irritant. The substance is reported not to elicit skin sensitisation (European Commission, 2000 and references herein).

Sodium molybdate, Na2MoO4, is useful as a source of molybdenum. It is often found as the dihydrate, Na2MoO4·2H2O. The molybdate(VI) anion is tetrahedral. Two sodium cations coordinate with every one anion.
Sodium Molybdate is a crystalline powder essential for the metabolism and development of plants and animals as a cofactor for enzymes.
Sodium molybdate (anhydrous) is an inorganic sodium salt having molybdate as the counterion. It has a role as a poison. It contains a molybdate.

General description
Sodium molybdate dihydrate (SMD) is a molybdic acid disodium salt. It crystallizes in the orthorhombic space group, Pbca.[1] The toxic effect of SMD on the avian species, northern bobwhite quail has been investigated.[2] Its ability to inhibit corrosion of 6082 wrought aluminum alloy has been studied in NaCl solution of chlorosulfonic acid.[3]

Application
Sodium molybdate dihydrate has been used as one of the phosphatase inhibitor during the Western blot analysis.[4]
It may be used to prepare:
• Shuttle-like barium molybdate (BaMoO4) microstructures under microwave conditions.[5]
• Nickel-molybdenum-zinc (NiMoZn) electrode.[6]
• Eu3+ doped lead molybdate (PbMoO4) nanocrystals (NCs) under microwave conditions.
Sodium molybdate was first synthesized by the method of hydration.[4] A more convenient synthesis is done by dissolving MoO3 in sodium hydroxide at 50–70 °C and crystallizing the filtered product.[3] The anhydrous salt is prepared by heating to 100 °C.