Oxalic acid is an acid with the formula HO2C-CO2H and is named ethanedioic acid. It's the simplest form of dicarboxylic acid. It's a crystalline solid that dissolves in water to become a colorless solution. It originated from investigators isolating oxalic acid from the commonly known wood sorrels. It is found naturally occurring in foods. Prolonged skin contact or excessive ingestion or inhalation of oxalic acid can be dangerous.

Oxalic acid is a colorless, poisonous substance. It's a caustic chemical. It can cause severe damage, such as burns or ulcers, on contact. In this article, we'll be discussing some precautions and methods you should take when handling oxalic acid.

1. If Inhaled:

Oxalic acid vapor is dangerous when inhaled. It causes serious burns to the respiratory tract, throat, and nose. If oxalic acid vapor or dust is inhaled it can cause nervousness, mucous membrane ulcers, vomiting, headache, nosebleed, back pain(as a result of kidney damage), weakness, and emaciation.

When Oxalic acid has been inhaled, remove the patient from exposure. If breathing has stopped, start rescue breathing and if heart action has stopped start CPR.

2. If Swallowed:

Oxalic acid is toxic due to its chelating and acidic properties. It's more toxic when ingested, even in the smallest amount. Once ingested, the person is likely going to experience mouth ulcers, vomiting blood, rapid shock, convulsion, twitching, and cardiovascular system collapse. When ingested oxalic acid binds with the calcium in the blood and goes on to form calcium oxalate, which might precipitate in the kidney tubules and brain.

3. In Contact With Eyes:

If oxalic acid comes in contact with the eyes, it's likely to cause serious eye irritation. It can also cause corneal injury or effect corrosive results in the eye. Oxalic acid effects are more likely to be serious to people with existing eye issues.

You should flush the eyes immediately after contact with a large amount of water for nothing less than 30 minutes. Remove contact lenses while flushing the eyes, if any are on. You should seek medical attention quickly.

4. In Contact With Skin:

You're likely to experience skin irritation when your skin comes in contact with oxalic acid. If absorbed through the skin, oxalic acid is harmful. Chemical burns from contact with oxalic acid at night also cause hypocalcemia. Skin rot has also been detected on the heads of people who handle oxalic acid without the use of a safety glove.

Quickly put off any clothes that were on during the point of contamination. Wash the contaminated skin with a lot of water and soap. Seek medical attention immediately.

5. Environmental Safety Measures:

Oxalic acid is hazardous and would be dangerous to the environment if it gets exposed. Here are some measures that can be employed to keep the environment safe from the environment;

  • Oxalic acid should be carefully disposed of in line with the local authority on harmful chemicals disposal.
  • Do not expose chemical to water bodies or general water sources.
  • Local exhaust ventilation should be used wherever oxalic acid is in use
  • General ventilation should be employed to control eye and skin irritation
  • If you get contaminated while using oxalic acid, don't take your contaminated clothes home

6. Suggestions For Safety Equipment:

Here are some advisable safety equipment that can be worn to keep yourself safe from the hazard of oxalic acid:

  • Clothing and Gloves

Wear personal clothing and gloves that wouldn't be degraded or permeated by oxalic acid. Recommendations can be provided by safety manufacturers and suppliers on the most reliable clothing and glove for whatever you're doing. Safety equipment suppliers recommend Silver shields, Neoprene, Viton, and Butyl as reliable glove clothing. Responder, Tychem, and TK are the recommended protective clothing for oxalic acid. All your protective clothing (headgear, gloves, footwear, and suits) should be clean and available always and be out on before you start the use of the chemical. 

  • Eye Protection

When handling oxalic acid, use eye protection with goggles or side shields. Wear splash and impact-resistant goggles. When using Goggles, wear face shields. Avoid the use of contact lenses when working with oxalic acid.

  • Respiratory Protection

Using respirators improperly is dangerous. Respirators should be used when there's a written program implemented. The respiratory equipment should be used according to the risk of exposure.

7. How To Store Oxalic Acid?

Oxalic acid when stored at ambient temperature tends to experience acid-medicated sugar breakdown(usual fructose) leading to the generation of HMF(hydroxymethylfurfural). This causes the oxalic acid solution to darken. When storing oxalic acid, you should keep it in a fridge at 4°C. The HMF levels would remain below toxic and the oxalic acid can last for about a year. However, oxalic acid shouldn't be stored for too long.

Oxalic acid should be stored in a tightly closed container and an area well-ventilated away from any type of combustible or moisture. Oxalic acid reacts with combustible materials which might lead to explosion and fire hazards.