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Soluble barium compounds are toxic. Barium sulfate is nearly insoluble and has very low toxicity. People routinely drink the stuff as a radiocontrast agent befo

Soluble barium compounds are toxic. Barium sulfate is nearly insoluble and has very low toxicity. People routinely drink the stuff as a radiocontrast agent before getting an x-ray.

potiuper 5y ago
And many of those roofing tiles will be burned at disposal, or in a house fire; Barium sulfide is poisonous - see carbothermal reduction.
- Turing_Machine 5y ago
  Vast amounts of barium sulfate are used to whiten paper, which is often burned, and no one worries about that.
  - pfdietz 5y ago
    Isn't that titanium dioxide?
    - adrian_b 5y ago
      Titanium dioxide a.k.a. titanium white is a different white pigment. Most white paints used nowadays contain titanium white. Nevertheless, many white plastics contain other white pigments instead of titanium white. Titanium white itself is inert, but when it is exposed to the sun light it can catalyze the destruction of organic substances like plastics or paint binders that have not been selected to be resistant to this. So when using titanium white outdoors, the white paint must be specified as UV resistant. I have not heard about paper that uses titanium white. That might be due to the higher cost of titanium white, which might be too much compared to the cost of paper.
- adrian_b 5y ago
  Even if some of the sulfate will be reduced to sulfide, making the barium soluble, the sulfide will be oxidized again by the air after some time, immobilizing any remaining barium. The barium that might have leached will be precipitated by the carbon dioxide from the air into barium carbonate. Any form of soluble barium left in the environment will end soon as either barium sulfate or barium carbonate, which are insoluble, thus non-poisonous. Barium is one of the least dangerous metals with high atomic number. You have to do something really stupid and deliberate with it in order to be able to poison anyone.

Soluble barium compounds are toxic. Barium sulfate is nearly insoluble and has very low toxicity. People routinely drink the stuff as a radiocontrast agent before getting an x-ray.

potiuper 5y ago

And many of those roofing tiles will be burned at disposal, or in a house fire; Barium sulfide is poisonous - see carbothermal reduction.

Turing_Machine 5y ago
Vast amounts of barium sulfate are used to whiten paper, which is often burned, and no one worries about that.
- pfdietz 5y ago
  Isn't that titanium dioxide?
  - adrian_b 5y ago
    Titanium dioxide a.k.a. titanium white is a different white pigment. Most white paints used nowadays contain titanium white. Nevertheless, many white plastics contain other white pigments instead of titanium white. Titanium white itself is inert, but when it is exposed to the sun light it can catalyze the destruction of organic substances like plastics or paint binders that have not been selected to be resistant to this. So when using titanium white outdoors, the white paint must be specified as UV resistant. I have not heard about paper that uses titanium white. That might be due to the higher cost of titanium white, which might be too much compared to the cost of paper.
adrian_b 5y ago
Even if some of the sulfate will be reduced to sulfide, making the barium soluble, the sulfide will be oxidized again by the air after some time, immobilizing any remaining barium. The barium that might have leached will be precipitated by the carbon dioxide from the air into barium carbonate. Any form of soluble barium left in the environment will end soon as either barium sulfate or barium carbonate, which are insoluble, thus non-poisonous. Barium is one of the least dangerous metals with high atomic number. You have to do something really stupid and deliberate with it in order to be able to poison anyone.