Oxalic acid, also known as ethanedioic acid, is a naturally occurring compound which is found in many different types of vegetables. In its solid form, it is colorless and has the appearance of a white crystal substance when purified. For humans, oral and topical applications of this acid are highly toxic to the body due to its bleach-like and corrosive properties. These properties are, however, useful for waste water applications and general cleaning and therefore this acid is commonly employed for these purposes today. As such, it is important to wear protective glasses, gloves and proper clothing in order to prevent accidental exposure to this harmful chemical.
Oxalic acid is often ingested by humans in very small amounts because it is inherent in foods, particularly broccoli, cucumbers, potatoes and sprouts. More concentrated amounts are present in dark, leafy greens in the form of oxalates. These foods are beneficial to health in small amounts. Foods such as spinach and broccoli are the most common sources of these types of oxalates.
The corrosive nature and toxicity of the acid can cause dangerous conditions for workers who are using the chemical. Well-ventilated areas are essential to avoid accidental breathing in of the acid, as well as latex gloves in order to prevent direct skin exposure to the acid crystals.
As a Cleaning Agent
The oxalic acid is an ideal chemical for cleaning purposes. Its bleach-like qualities make it perfect for sterilizing household items. It is also efficient in removing rust on various different surfaces. Stains on counters, bathtubs and kitchen sinks can be removed through careful application of this chemical. Today, it can be found as a passive ingredient in various cleaning products, bleaches and detergents.
For Industrial Uses
This acid is sometimes used in mineral processing mechanisms. Its bleaching properties can be used to sterilize equipment in a number of corporate environments. Textile mills and factories use it for bleaching in order to color cloths. Medical companies occasionally use the acid to purify certain chemicals or to dilute them further.
Oxalic can cause unwanted side effects to those who ingest a high amount of food containing the chemical or use drugs with concentrated amounts of it present. Oftentimes, these side effects take years to develop as the oxalic acid concentration is too low. Over time, oxalate crystals can form in the body. Most of these crystals form kidney stones at a later stage, causing various complications. More serious side effects can include kidney failure and gastrointestinal disorders, especially after certain types of surgery.
People who consume large amounts of vitamin C are most at risk. This is because when vitamin C is broken down by the body, oxalic acid is released and may accumulate in large amounts to form kidney stones.
The corrosive nature of the acid makes it difficult for the body to efficiently absorb metal ions such as magnesium and calcium when present in large amounts.