Barium sulfate BaSO4
BaSO4 · CAS 7727-43-7 · orthorhombic
Barium sulfate (BaSO4) is a dense, white, very poorly water-soluble barium salt.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Density
4.49 g/cm³
Filler capacity
Up to 70%
Melting
1580 °C
Water solubility
2.448 mg/L
Recipe, share of the weight
- Ba not statedBarium
- S not statedSulfur
- O not statedOxygen
Best for
Dense X-ray and gamma shielding fillers where density matters more than mechanical strength (USGS: used as aggregate in high-density radiation-shielding concrete)
Weakest at
No space, vacuum or long-term radiation-durability data were found in the sources read; hazard data are inconsistent between sources
Risk at a glance
- People None found. Mixed: most reports not classified; some list H372
- If it fails Moderate. Violent reaction with aluminium powder
- Corrosion Low. Barium sulfate dissolves only in concentrated, hot sulfuric acid among the solvents the Chembox lists.
Quick facts: BaSO4
| Property | Value | Basis |
|---|---|---|
| Density | 4.48 to 4.5 g/cm³ | 4 sourced values across conditions |
| Melting point | 1,580 °C | 1 sourced value |
What is the density of Barium sulfate (BaSO4)?
Barium sulfate (BaSO4) has a density of 4.48 to 4.5 g/cm³. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the melting point of Barium sulfate (BaSO4)?
Barium sulfate (BaSO4) has a melting point of 1,580 °C. The source and test conditions are listed in the properties table on this page.
What is Barium sulfate (BaSO4) used for?
Uses recorded in the sources include Concrete aggregate for shielding around X-ray units; Filler in polymer composites.
Why it exists
Barium sulfate is a dense, poorly soluble barium salt that is used where a heavy, inert filler is needed. Its density and barium content let it block X-rays and gamma rays, so it is added to polymers and concrete for radiation shielding. The USGS lists its main uses as a weighting agent in drilling fluids, a filler and extender in paints and plastics, and aggregate in high-density concrete for radiation shielding. The 2026 systematic review of shielding concretes calls barite and magnetite concretes among the most reliable materials for medical radiation rooms, nuclear containment structures and accelerator facilities. No space or vacuum test was found.
Where it's used
Concrete for X-ray and gamma shielding
The USGS says barite significantly blocks X-ray and gamma-ray emissions, so it is used as aggregate in high-density concrete around X-ray units in hospitals, nuclear power plants and university nuclear research facilities.
Polymer composites
Barium sulfate is used as a filler for polypropylene and polystyrene plastics in proportions up to 70%, and such composites are also used as X-ray shielding materials.
Drilling fluids
Wikipedia says the largest use of barium sulfate is as a component of oil-well drilling fluid, where it raises the density of the fluid and reduces the chance of a blowout.
Recipe
BaSO4
Barium sulfate is BaSO₄, a salt of barium and sulfate. It occurs in nature as the mineral barite, which is the main commercial source of barium according to the Wikipedia article. The formula BaSO₄ has the barium, sulfur and oxygen atoms listed in the parts.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Barium Ba | not stated | The heavy element that gives the material its high density and its ability to absorb X-rays and gamma rays. |
| Sulfur S | not stated | Forms the sulfate group that binds the barium into a stable, insoluble salt. |
| Oxygen O | not stated | Complete the sulfate group around the sulfur atom. |
Weight shares are as printed in the sources.
What it can do
Density
4.49 g/cm³
measured
The Chembox gives a density of 4.49 g/cm3, and the ICSC card gives 4.5 g/cm3. The barite mineral has a density of 4.48 g/cm3 according to Ahmad et al. (2024).
Filler capacity
Up to 70%
measured
Polymer composites carry barium sulfate in proportions up to 70%, per Wikipedia. The filler raises the density of the plastic and adds X-ray opacity.
Melting
1580 °C
measured
The Chembox gives a melting point of 1580 °C. The ICSC card gives no melting point and says the material decomposes at 1600 °C.
Water solubility
2.448 mg/L
measured
The Chembox gives a water solubility of 2.448 mg/L at 20 °C, which keeps the solid largely undissolved in water.
How it compares
Barium sulfate is the pure, manufactured form of the mineral barite, and the two are the same chemical. Ahmad et al. (2024) give a density of 4.48 g/cm3 for barite, and the Chembox gives 4.49 g/cm3 for barium sulfate; the two values are close and both are recorded. Barium sulfate used in concrete is a different material system with different strength and attenuation figures, which are set out in the separate barite-heavyweight concrete profile.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details.
| Measurement | BaSO4 |
|---|---|
| Capacity and energy | |
| Molar heat capacity | 101.7 J/(mol K)6 |
| Thermal behavior and safety | |
| Melting pointValue in the Chembox of an encyclopedia article | 1580 °C |
| Physical and electrical | |
| Density (Chembox) | 4.49 g/cm³1 |
| Density (ICSC 0827) | 4.5 g/cm³2 |
| Specific gravity of barite (mineral data page)Value in a note on a mineral data page | 4.48 gm/cc |
| Density of barite as a heavy mineral (Ahmad et al. 2024)Value in the text of an open-access paper | 4.48 g/cm³ |
| Temperature behavior | |
| Decomposition temperature | 1600 °C4 |
| Other measurements | |
| Molar mass | 233.4 g/mol3 |
| Solubility in water at 20 °C | 2.448 mg/L5 |
| Refractive index (alpha form)Value in the Chembox of an encyclopedia article | 1.636 - |
| Standard molar entropy | 132 J/(mol·K)7 |
| Filler loading in polymers | < 70 %8 |
| MAK (as barium, respirable fraction) | 0.3 mg/m39 |
| TLV (inhalable fraction) | 4 ppm10 |
Why choose it, and why not
Good for
- Dense filler for X-ray and gamma shielding in polymers and concrete, per the USGS and Wikipedia.
- Very low water solubility (Chembox), so the solid stays largely undissolved in water.
Watch out for
- Dust hazard, and one notification lists H372 for repeated exposure.
- Reacts violently with aluminium powder, per the ICSC card.
- No space, vacuum or long-term radiation-durability data in the sources read.
- The ICSC card and the Chembox disagree on water solubility.
Barium sulfate is a dense, very poorly soluble filler for X-ray and gamma shielding. Its main hazards are dust and reaction with aluminium powder, and no space test was found.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density (Chembox) | Value in the infobox of an encyclopedia article, which cites secondary references | form barium sulfate, solidbasis Chembox value for the pure compound | — |
| 2 | Density (ICSC 0827) | Value printed on the International Chemical Safety Card | form barium sulfate, as listed on the card | The card and the Chembox agree to the precision the card prints; both are recorded. |
| 3 | Molar mass | Value printed in the infobox of an encyclopedia article | basis molar mass of BaSO4 as printed in the Chembox | — |
| 4 | Decomposition temperature | Value printed on the International Chemical Safety Card | basis statement on the card: 'Decomposes at 1600°C'note The ICSC card lists no melting point | — |
| 5 | Solubility in water at 20 °C | Value in the Chembox; the same box gives 2.85 mg/L at 30 °C | temperature 20 °Csolvent water | The ICSC card gives 'none' for solubility in water, which disagrees with the Chembox figure; both are recorded in corrosion. |
| 6 | Molar heat capacity | Value in the Chembox thermochemistry section, which cites a textbook | basis Chembox thermochemistry field; temperature not stated in the box | — |
| 7 | Standard molar entropy | Value in the Chembox thermochemistry section, which cites a textbook | basis standard conditions as given in the Chembox thermochemistry section | — |
| 8 | Filler loading in polymers | Value stated in the text of an encyclopedia article | polymers polypropylene and polystyrenebasis maximum proportion stated in the text | — |
| 9 | MAK (as barium, respirable fraction) | Value printed on the International Chemical Safety Card | basis MAK value printed on the card, as Ba, respirable fractioncategory peak limitation category II(8) | — |
| 10 | TLV (inhalable fraction) | Value printed on the International Chemical Safety Card | basis TLV as TWA, inhalable fraction, as printed on the card | The card prints the unit ppm for a dust limit; it is copied as printed. |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Concentrated, hot sulfuric acid | low | Barium sulfate dissolves only in concentrated, hot sulfuric acid among the solvents the Chembox lists.1 |
| Water | low | The sources disagree on water solubility: the Chembox gives a figure, while the ICSC card says none.2 |
| Fire and high temperature | low | The card says the material is not combustible, but it gives off irritating or toxic fumes in a fire.3 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Concentrated, hot sulfuric acid | The Chembox lists barium sulfate as soluble in concentrated, hot sulfuric acid and as insoluble in ethanol. It gives a water solubility of 2.448 mg/L at 20 °C, so it does not dissolve appreciably in water. | basis solubility fields in the Chembox; no test of corrosion rates is given |
| 2 | Water | The ICSC card gives 'none' for solubility in water. The Chembox gives 2.448 mg/L at 20 °C. Both are recorded here and neither is filled in. | basis two sources compared side by side |
| 3 | Fire and high temperature | ICSC 0827 says 'Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.' It also says the material decomposes at 1600 °C. The card does not name the fumes. | basis fire-fighting section of the card; the gases are not named |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
PubChem's aggregated summary says most company reports do not meet GHS hazard criteria, but other notifications list hazard statements, including a repeated-exposure hazard.
- Most reports
- PubChem's summary reads: 'This chemical does not meet GHS hazard criteria for 91% (1648 of 1811) of all reports.'
- Harmful if swallowed
- One notification lists H302, harmful if swallowed, with the signal word Warning.
- Repeated exposure
- Another notification lists H372, causes damage to organs through prolonged or repeated exposure, with the signal word Danger.
- Dust
- The ICSC card advises preventing dust from spreading and says repeated or prolonged inhalation of dust may affect the lungs, possibly as baritosis.
Handling powder
Barium sulfate is usually handled as a powder or a filler, so the main concerns are dust and mixing with reactive metals.
- Reaction
- The ICSC card warns that the material reacts violently with aluminium powder.
- Fire
- The card says it is not combustible but gives off irritating or toxic fumes in a fire.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Violent reaction with aluminium powdermoderate severity | Contact with aluminium powder in a mix or spillICSC 0827 lists 'Reacts violently with aluminium powder' under chemical dangers. |
Handling and storage
- The ICSC card says to prevent dispersion of dust, use local exhaust or breathing protection, and wear protective gloves and safety spectacles.
- The card says to sweep spilled substance into covered containers and, if appropriate, to moisten it first to prevent dusting, using a particulate filter respirator.
- No barium sulfate safety data sheet from a supplier was read in this run. Check the supplier's data sheet before handling bulk powder.
Mitigations
- The ICSC card's eye first aid is to rinse first with plenty of water for several minutes, then refer for medical attention.
Supply and geography
How common the raw materials are and where they come from.
Barite (barium sulfate mineral)
- Top producers (2025)
- India 34.5%, China 25.3%, Morocco 11.5%, Kazakhstan 8%, Mexico 3.4%
- Critical mineral lists
- EU: listed
- Recycling
- USGS barite chapter: 'Recycling: None.'
- Substitutes
- USGS: 'there are no large-scale alternatives to barite in oil- and gas-drilling fluids'. It names calcium carbonate, hematite, ilmenite and manganese tetroxide as the most common alternatives in specific circumstances.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: barium-sulfate
spore_version: 0.2
family: barium
name: Barium sulfate
abbreviation: BaSO4
role: X-ray and gamma shielding filler and radiocontrast agent
category: shielding
type: spot-shields
summary: |
Barium sulfate (BaSO4) is a dense, white, very poorly water-soluble barium salt. In nature it occurs as the mineral barite. The Wikipedia Chembox gives a density of 4.49 g/cm3, and the ILO International Chemical Safety Card 0827 gives 4.5 g/cm3. The material is used as a heavy filler in polymers and as aggregate in radiation-shielding concrete, where it blocks X-rays and gamma rays.
best_for: 'Dense X-ray and gamma shielding fillers where density matters more than mechanical strength (USGS: used as aggregate in high-density radiation-shielding concrete)'
weakest_at: No space, vacuum or long-term radiation-durability data were found in the sources read; hazard data are inconsistent between sources
identity:
formula: BaSO4
cas: 7727-43-7
crystal_system: orthorhombic
source: wiki-barium-sulfate
where: 'Chembox: formula BaSO4, crystal structure orthorhombic. CAS 7727-43-7 is printed in the Chembox and on ICSC 0827 (icsc-0827)'
tags:
stresses:
- total-radiation-dose
applications:
- radiation-shielding
properties:
- benchmark: density
label: Density (Chembox)
value: 4.49
unit: g/cm3
scope: material
conditions:
form: barium sulfate, solid
basis: Chembox value for the pure compound
method: Value in the infobox of an encyclopedia article, which cites secondary references
status: ground
source: wiki-barium-sulfate
where: Chembox, Density field
- benchmark: density
label: Density (ICSC 0827)
value: 4.5
unit: g/cm3
scope: material
conditions:
form: barium sulfate, as listed on the card
method: Value printed on the International Chemical Safety Card
status: ground
note: The card and the Chembox agree to the precision the card prints; both are recorded.
source: icsc-0827
where: Physical and chemical information, Density
- benchmark: density
label: Specific gravity of barite (mineral data page)
value: 4.48
unit: gm/cc
scope: material
conditions:
material: barite, the mineral form of BaSO4
method: Value in a note on a mineral data page
status: ground
source: webmineral-barite
where: Electron Density section, note 'Specific Gravity of Barite =4.48 gm/cc'
- benchmark: density
label: Density of barite as a heavy mineral (Ahmad et al. 2024)
value: 4.48
unit: g/cm3
scope: material
conditions:
material: barite, a heavy mineral
basis: value the paper gives for barite, citing refs 27 and 41
method: Value in the text of an open-access paper
status: ground
source: ahmad2024-sci
where: 'Density of concrete section, first paragraph (text: ''a heavy mineral with a density of 4.48 g/cm 3'')'
- benchmark: molar_mass
label: Molar mass
value: 233.39
unit: g/mol
scope: material
conditions:
basis: molar mass of BaSO4 as printed in the Chembox
method: Value printed in the infobox of an encyclopedia article
status: ground
source: wiki-barium-sulfate
where: Chembox, Molar mass field
- benchmark: melting_point
label: Melting point
value: 1580
unit: °C
scope: material
conditions:
form: barium sulfate, solid
note: The same box gives a boiling point of 1600 °C with the note 'decomposes'
method: Value in the Chembox of an encyclopedia article
status: ground
source: wiki-barium-sulfate
where: Chembox, MeltingPt field
- benchmark: decomposition_temperature
label: Decomposition temperature
value: 1600
unit: °C
scope: material
conditions:
basis: 'statement on the card: ''Decomposes at 1600°C'''
note: The ICSC card lists no melting point
method: Value printed on the International Chemical Safety Card
status: ground
source: icsc-0827
where: Physical and chemical information, decomposition statement
- benchmark: water_solubility
label: Solubility in water at 20 °C
value: 2.448
unit: mg/L
scope: material
conditions:
temperature: 20 °C
solvent: water
method: Value in the Chembox; the same box gives 2.85 mg/L at 30 °C
status: ground
note: The ICSC card gives 'none' for solubility in water, which disagrees with the Chembox figure; both are recorded in corrosion.
source: wiki-barium-sulfate
where: Chembox, Solubility field
- benchmark: refractive_index
label: Refractive index (alpha form)
value: 1.636
unit: '-'
scope: material
conditions:
form: alpha
basis: Chembox RefractIndex field, marked alpha
method: Value in the Chembox of an encyclopedia article
status: ground
source: wiki-barium-sulfate
where: Chembox, RefractIndex field
- benchmark: heat_capacity_molar
label: Molar heat capacity
value: 101.7
unit: J/(mol K)
scope: material
conditions:
basis: Chembox thermochemistry field; temperature not stated in the box
method: Value in the Chembox thermochemistry section, which cites a textbook
status: ground
source: wiki-barium-sulfate
where: Chembox, Thermochemistry section, HeatCapacity field
- benchmark: standard_molar_entropy
label: Standard molar entropy
value: 132
unit: J/(mol·K)
scope: material
conditions:
basis: standard conditions as given in the Chembox thermochemistry section
method: Value in the Chembox thermochemistry section, which cites a textbook
status: ground
source: wiki-barium-sulfate
where: Chembox, Thermochemistry section, Entropy field
- benchmark: filler_loading
label: Filler loading in polymers
value: 70
bound: upper
unit: '%'
scope: material
conditions:
polymers: polypropylene and polystyrene
basis: maximum proportion stated in the text
method: Value stated in the text of an encyclopedia article
status: ground
source: wiki-barium-sulfate
where: Uses, plastics filler paragraph ('in proportions up to 70%')
- benchmark: occupational_exposure_limit
label: MAK (as barium, respirable fraction)
value: 0.3
unit: mg/m3
scope: material
conditions:
basis: MAK value printed on the card, as Ba, respirable fraction
category: peak limitation category II(8)
method: Value printed on the International Chemical Safety Card
status: ground
source: icsc-0827
where: Occupational exposure limits, MAK
- benchmark: occupational_exposure_limit
label: TLV (inhalable fraction)
value: 4
unit: ppm
scope: material
conditions:
basis: TLV as TWA, inhalable fraction, as printed on the card
method: Value printed on the International Chemical Safety Card
status: ground
note: The card prints the unit ppm for a dust limit; it is copied as printed.
source: icsc-0827
where: Occupational exposure limits, TLV
corrosion:
- environment: Concentrated, hot sulfuric acid
headline: Barium sulfate dissolves only in concentrated, hot sulfuric acid among the solvents the Chembox lists.
effect: The Chembox lists barium sulfate as soluble in concentrated, hot sulfuric acid and as insoluble in ethanol. It gives a water solubility of 2.448 mg/L at 20 °C, so it does not dissolve appreciably in water.
rating: low
conditions:
basis: solubility fields in the Chembox; no test of corrosion rates is given
source: wiki-barium-sulfate
where: Chembox, SolubleOther and Solvent fields
- environment: Water
headline: 'The sources disagree on water solubility: the Chembox gives a figure, while the ICSC card says none.'
effect: The ICSC card gives 'none' for solubility in water. The Chembox gives 2.448 mg/L at 20 °C. Both are recorded here and neither is filled in.
rating: low
conditions:
basis: two sources compared side by side
source: icsc-0827
where: Physical and chemical information, Solubility in water
- environment: Fire and high temperature
headline: The card says the material is not combustible, but it gives off irritating or toxic fumes in a fire.
effect: ICSC 0827 says 'Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.' It also says the material decomposes at 1600 °C. The card does not name the fumes.
rating: low
conditions:
basis: fire-fighting section of the card; the gases are not named
source: icsc-0827
where: Fire-fighting; Physical and chemical information
risks:
hazards:
- text: 'PubChem''s aggregated summary reads: ''This chemical does not meet GHS hazard criteria for 91% (1648 of 1811) of all reports.'''
ghs: []
source: pubchem-barium-sulfate
where: Safety and Hazards, GHS Classification (CID 24414), first summary
- text: 'One ECHA notification summary lists ''H302 (16.6%): Harmful if swallowed'' and ''H332 (16.6%): Harmful if inhaled'', with the signal word Warning.'
ghs:
- H302
- H332
source: pubchem-barium-sulfate
where: Safety and Hazards, GHS Classification, Warning notification
- text: 'A separate notification lists ''H372: Causes damage to organs through prolonged or repeated exposure'', with the signal word Danger, and also lists H402 and H412 for aquatic harm.'
ghs:
- H372
- H402
- H412
source: pubchem-barium-sulfate
where: Safety and Hazards, GHS Classification, Danger notification
- text: The ICSC card says repeated or prolonged inhalation of dust particles may cause effects on the lungs, which it says may lead to baritosis, a form of benign pneumoconiosis.
ghs: []
source: icsc-0827
where: Exposure and health effects, long-term or repeated exposure
failure_risks:
- mode: Violent reaction with aluminium powder
trigger: Contact with aluminium powder in a mix or spill
consequence: ICSC 0827 lists 'Reacts violently with aluminium powder' under chemical dangers.
severity: moderate
source: icsc-0827
where: Physical and chemical information, Chemical dangers (severity assessed by Space Mushroom from the card's wording)
side_effects: []
handling:
- text: The ICSC card says to prevent dispersion of dust, use local exhaust or breathing protection, and wear protective gloves and safety spectacles.
source: icsc-0827
where: Prevention and handling
- text: The card says to sweep spilled substance into covered containers and, if appropriate, to moisten it first to prevent dusting, using a particulate filter respirator.
source: icsc-0827
where: Spillage disposal
- text: No barium sulfate safety data sheet from a supplier was read in this run. Check the supplier's data sheet before handling bulk powder.
source: pubchem-barium-sulfate
where: Not found in this run; PubChem record read for the hazard entries above
mitigations:
- text: The ICSC card's eye first aid is to rinse first with plenty of water for several minutes, then refer for medical attention.
source: icsc-0827
where: First aid, Eyes
uses:
- application: radiation-shielding
device: Concrete aggregate for shielding around X-ray units
example: The USGS says barite 'significantly blocks X-ray and gamma-ray emissions', so it is used as aggregate in high-density concrete for radiation shielding around X-ray units in hospitals, nuclear powerplants and university nuclear research facilities.
source: usgs-mcs2026-barite
where: Domestic Production and Use, paragraph 3
- application: radiation-shielding
device: Filler in polymer composites
example: Barium sulfate is used as a filler for polypropylene and polystyrene plastics in proportions up to 70%, and such composites are also used as X-ray shielding materials, per Wikipedia.
source: wiki-barium-sulfate
where: Uses, plastics filler paragraph
supply:
- subject: Barite (barium sulfate mineral)
producers:
- country: India
share_percent: 34.5
year: 2025
- country: China
share_percent: 25.3
year: 2025
- country: Morocco
share_percent: 11.5
year: 2025
- country: Kazakhstan
share_percent: 8
year: 2025
- country: Mexico
share_percent: 3.4
year: 2025
critical_lists:
- list: EU critical raw materials list (Regulation (EU) 2024/1252, as shown on the European Commission page, which lists Baryte)
listed: true
recycling: 'USGS barite chapter: ''Recycling: None.'''
substitutes:
- 'USGS: ''there are no large-scale alternatives to barite in oil- and gas-drilling fluids''. It names calcium carbonate, hematite, ilmenite and manganese tetroxide as the most common alternatives in specific circumstances.'
source: usgs-mcs2026-barite
where: World Mine Production and Reserves table, 2025 (world total 8,700 thousand metric tons; shares calculated by Space Mushroom against that total, which includes Other countries); Recycling; Substitutes
media: []
documents:
- title: 'International Chemical Safety Card 0827: Barium sulfate (ILO and WHO)'
type: datasheet
url: https://chemicalsafety.ilo.org/dyn/icsc/showcard.display?p_card_id=0827
year: 1999
- title: 'Mineral Commodity Summaries 2026: Barite'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-barite.pdf
year: 2026
- title: 'PubChem: Barium Sulfate (CID 24414), GHS classification and CAS'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Barium-sulfate
year: 2026
- title: Enhancing shielding efficiency of ordinary and barite concrete in radiation shielding utilizations (Scientific Reports 14, 26029)
type: paper
url: https://www.nature.com/articles/s41598-024-76402-0
year: 2024
- title: 'Radiation Shielding Performance of Different Concrete Materials: A Systematic Review (arXiv 2601.10336)'
type: paper
url: https://www.arxiv.org/pdf/2601.10336
year: 2026
gaps:
- No space, vacuum, lunar or Mars test of barium sulfate was found in the sources read in this run.
- The solubility product and the magnetic susceptibility are printed in the Chembox in scientific notation, so they are not recorded.
- The standard enthalpy of formation is printed in the Chembox with a Unicode minus sign that the value check cannot match, so it is not recorded.
- Atomic weights for the recipe parts were not found in a source read in this run, so they are left out.
- Crustal abundance and the USGS 2025 critical-minerals listing were not found in a source read in this run; only the EU listing is recorded.
- No designation entry (UNS, EN, ASTM or trade code) was added. The EC and UN numbers are printed on the ICSC card and the Chembox, but they do not fit the designation systems list.
- The melting point is given only in the Chembox; the ICSC card lists no melting point.
- Hazard entries rest on the PubChem aggregated GHS summary and the ICSC card. No supplier safety data sheet was read.
- Mohs hardness was not recorded because no unit was printed on the source page.
- Shielding performance of barium sulfate as a concrete aggregate is covered in the separate barite-heavyweight concrete profile and is not repeated here.
- Type spot-shields is the nearest existing shielding type in src/data/taxonomy.ts (the same type the barite concrete profile uses); it is an approximate fit for a mineral filler and not an exact one.
- Some property names (molar_mass, decomposition_temperature, water_solubility, heat_capacity_molar, standard_molar_entropy, filler_loading, occupational_exposure_limit) are short snake_case names, not canonical names in spores/property-canon.yaml.
license: CC-BY-4.0
updated: '2026-11-02'
review:
status: draft
method: assistant
checked_values: 14
unreachable: 1
caveats: 3
note: Written by an AI assistant on 2026-11-02 from eight sources read in this run. Values are copied as printed. The PubChem page is behind a browser check, so its GHS entries were read from the PubChem data service instead. The USGS 2025 critical-minerals page was not read.
story:
recipe:
line: Barium sulfate is BaSO₄, a salt of barium and sulfate. It occurs in nature as the mineral barite, which is the main commercial source of barium according to the Wikipedia article. The formula BaSO₄ has the barium, sulfur and oxygen atoms listed in the parts.
parts:
- name: Barium
symbol: Ba
role: The heavy element that gives the material its high density and its ability to absorb X-rays and gamma rays.
- name: Sulfur
symbol: S
role: Forms the sulfate group that binds the barium into a stable, insoluble salt.
- name: Oxygen
symbol: O
role: Complete the sulfate group around the sulfur atom.
risk_groups:
- title: For people
level: 0
verdict: 'Mixed: most reports not classified; some list H372'
lead: PubChem's aggregated summary says most company reports do not meet GHS hazard criteria, but other notifications list hazard statements, including a repeated-exposure hazard.
points:
- label: Most reports
line: 'PubChem''s summary reads: ''This chemical does not meet GHS hazard criteria for 91% (1648 of 1811) of all reports.'''
- label: Harmful if swallowed
line: One notification lists H302, harmful if swallowed, with the signal word Warning.
- label: Repeated exposure
line: Another notification lists H372, causes damage to organs through prolonged or repeated exposure, with the signal word Danger.
- label: Dust
line: The ICSC card advises preventing dust from spreading and says repeated or prolonged inhalation of dust may affect the lungs, possibly as baritosis.
- title: Handling powder
lead: Barium sulfate is usually handled as a powder or a filler, so the main concerns are dust and mixing with reactive metals.
points:
- label: Reaction
line: The ICSC card warns that the material reacts violently with aluminium powder.
- label: Fire
line: The card says it is not combustible but gives off irritating or toxic fumes in a fire.
why: Barium sulfate is a dense, poorly soluble barium salt that is used where a heavy, inert filler is needed. Its density and barium content let it block X-rays and gamma rays, so it is added to polymers and concrete for radiation shielding. The USGS lists its main uses as a weighting agent in drilling fluids, a filler and extender in paints and plastics, and aggregate in high-density concrete for radiation shielding. The 2026 systematic review of shielding concretes calls barite and magnetite concretes among the most reliable materials for medical radiation rooms, nuclear containment structures and accelerator facilities. No space or vacuum test was found.
uses:
- where: Concrete for X-ray and gamma shielding
line: The USGS says barite significantly blocks X-ray and gamma-ray emissions, so it is used as aggregate in high-density concrete around X-ray units in hospitals, nuclear power plants and university nuclear research facilities.
- where: Polymer composites
line: Barium sulfate is used as a filler for polypropylene and polystyrene plastics in proportions up to 70%, and such composites are also used as X-ray shielding materials.
- where: Drilling fluids
line: Wikipedia says the largest use of barium sulfate is as a component of oil-well drilling fluid, where it raises the density of the fluid and reduces the chance of a blowout.
can_do:
- label: Density
benchmark: density
line: The Chembox gives a density of 4.49 g/cm3, and the ICSC card gives 4.5 g/cm3. The barite mineral has a density of 4.48 g/cm3 according to Ahmad et al. (2024).
- label: Filler capacity
benchmark: filler_loading
value: Up to 70%
line: Polymer composites carry barium sulfate in proportions up to 70%, per Wikipedia. The filler raises the density of the plastic and adds X-ray opacity.
- label: Melting
benchmark: melting_point
line: The Chembox gives a melting point of 1580 °C. The ICSC card gives no melting point and says the material decomposes at 1600 °C.
- label: Water solubility
benchmark: water_solubility
line: The Chembox gives a water solubility of 2.448 mg/L at 20 °C, which keeps the solid largely undissolved in water.
compare: Barium sulfate is the pure, manufactured form of the mineral barite, and the two are the same chemical. Ahmad et al. (2024) give a density of 4.48 g/cm3 for barite, and the Chembox gives 4.49 g/cm3 for barium sulfate; the two values are close and both are recorded. Barium sulfate used in concrete is a different material system with different strength and attenuation figures, which are set out in the separate barite-heavyweight concrete profile.
compare_rows:
- label: Density
benchmark: density
- label: Melting point
benchmark: melting_point
- label: Water solubility
benchmark: water_solubility
handling:
- Prevent dust from spreading, and use local exhaust or breathing protection, per the ICSC card.
- Wear protective gloves and safety spectacles when handling the powder.
- Keep it away from aluminium powder, which it reacts with violently.
- Check the supplier's safety data sheet before handling bulk powder, since none was read here.
good_for:
- Dense filler for X-ray and gamma shielding in polymers and concrete, per the USGS and Wikipedia.
- Very low water solubility (Chembox), so the solid stays largely undissolved in water.
watch_out:
- Dust hazard, and one notification lists H372 for repeated exposure.
- Reacts violently with aluminium powder, per the ICSC card.
- No space, vacuum or long-term radiation-durability data in the sources read.
- The ICSC card and the Chembox disagree on water solubility.
verdict: Barium sulfate is a dense, very poorly soluble filler for X-ray and gamma shielding. Its main hazards are dust and reaction with aluminium powder, and no space test was found.
sources:
wiki-barium-sulfate:
title: Barium sulfate (Wikipedia, Chembox and Uses sections)
id: Wikipedia article 'Barium sulfate' (accessed 2026-11-02)
url: https://en.wikipedia.org/wiki/Barium_sulfate
year: 2026
kind: web
license: CC BY-SA 4.0
icsc-0827:
title: 'International Chemical Safety Card 0827: Barium sulfate (ILO and WHO)'
id: ICSC 0827, October 1999; CAS 7727-43-7
url: https://chemicalsafety.ilo.org/dyn/icsc/showcard.display?p_card_id=0827
year: 1999
kind: datasheet
license: ILO and WHO copyright notice on the card; cited, not reproduced
usgs-mcs2026-barite:
title: Mineral Commodity Summaries 2026, Barite
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-barite.pdf
year: 2026
kind: report
license: public domain (USGS)
pubchem-barium-sulfate:
title: PubChem compound record, Barium Sulfate (CID 24414)
id: CID 24414; CAS 7727-43-7
url: https://pubchem.ncbi.nlm.nih.gov/compound/Barium-sulfate
year: 2026
kind: database
license: public domain (NCBI)
ec-crm:
title: Critical raw materials (European Commission, list of 34 critical raw materials under Regulation (EU) 2024/1252)
id: Regulation (EU) 2024/1252
url: https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en
year: 2024
kind: web
license: European Commission web page
webmineral-barite:
title: 'Webmineral: Barite mineral data'
id: webmineral.com, barite data page
url: https://webmineral.com/data/Barite.shtml
year: 2026
kind: database
license: web page (licence not checked)
ahmad2024-sci:
title: Enhancing shielding efficiency of ordinary and barite concrete in radiation shielding utilizations
id: doi:10.1038/s41598-024-76402-0 (Scientific Reports 14, 26029)
url: https://www.nature.com/articles/s41598-024-76402-0
year: 2024
kind: paper
license: open-access journal (licence not checked)
subaar2026:
title: 'Radiation Shielding Performance of Different Concrete Materials: A Systematic Review'
id: arXiv:2601.10336
url: https://www.arxiv.org/pdf/2601.10336
year: 2026
kind: paper
license: arXiv preprint (licence not checked)
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Barium sulfate (Wikipedia, Chembox and Uses sections) | web | 2026 | 11 values | |
| International Chemical Safety Card 0827: Barium sulfate (ILO and WHO) | datasheet | 1999 | 11 values | |
| Mineral Commodity Summaries 2026, Barite | report | 2026 | 2 values | |
| PubChem compound record, Barium Sulfate (CID 24414) | database | 2026 | 4 values | |
| Critical raw materials (European Commission, list of 34 critical raw materials under Regulation (EU) 2024/1252) | web | 2024 | 0 values | |
| Webmineral: Barite mineral data | database | 2026 | 1 value | |
| Enhancing shielding efficiency of ordinary and barite concrete in radiation shielding utilizations | paper | 2024 | 1 value | |
| Radiation Shielding Performance of Different Concrete Materials: A Systematic Review | paper | 2026 | 0 values |
Updated