SPOKANE, Wash. — Six Union Pacific railcars derailed in a Spokane railyard on Tuesday night, including cars containing molten sulfur.

The train derailed near Havana Street and Sprague Avenue on Tuesday night at about 11 p.m., according to a UP spokesperson. No injuries were reported and the main line was not affected.

The six cars that derailed contained molten sulfur, according to a UP spokesman. The spokesman also said that there were no leaks of sulfur, and the only material that spilled was timber.

But this still raises questions, including: What is molten sulfur and how dangerous is the substance?

What is molten sulfur?

Molten Sulfur is a “pale yellow crystalline solid with a faint odor of rotten eggs,” according to the National Oceanic and Atmospheric Administration. The substance in its molten form is transferred and a liquid ranging from a red to a yellow color, according to the NOAA.

The NOAA lists uses for molten sulfur as a key component in the production of sulfuric acid, which is used for things such as fertilizer production, as well as in oil refining and paper manufacturing.

Derivatives of sulfur are also used in a range of industries, including dyes, pigments, drugs, explosives, inorganic salts and detergents to name a few, according to Encyclopedia Britannica.

When it burns, it produces a toxic gas and burns with a pale blue color that is sometimes difficult to see in daylight, according to the NOAA.

How dangerous is molten sulfur?

The chemical poses a fire risk and could explode above 450 degrees, and is usually transported at 290 degrees to keep it from solidifying, according to the NOAA.

According to both the NOAA and the New Jersey Department of Health, on a scale of zero to four, the material is ranked as a two on the health risk scale and a one on the flammability scale. This means it poses a “moderate” health risk and a “slight” fire risk.

If it catches fire, a poisonous gas known as hydrogen sulfide can be released, according to the NJDOH. Also, if it comes into contact with skin, it can cause burns.

Other symptoms of exposure to sulfur include headache, nausea, and vomiting, allergy-like symptoms and irritation of the lungs, throat and nose.

When it comes to treatment of sulfur injuries, it is recommended to immediately cease exposure to breathing in the material or any gases created, as well as immediately rinsing exposed eyes and any skin that came in contact with the chemical. Rinse eyes with water and skin with water, or petroleum jelly or mineral oil.

When it comes to affected clothing, it could cause more burns, and when removing the clothing, it is important to be careful as it could tear skin weakened by a sulfur burn.

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