How do organic and inorganic arsenic differ?

It is necessary to distinguish between two forms of arsenic: organic arsenic, which is almost harmless to humans, and inorganic arsenic, which is highly toxic to health.

Identifying two types of arsenic

Inorganic arsenic is the arsenic (As) atom in metallic form, either pure or in compounds where arsenic is not bonded to a carbon (C) group, such as in arsenic trichloride (AsCl3). The two main types of inorganic arsenic are arsenite and arsenate, both of which are toxic and carcinogenic.

Organic arsenic is an organic compound containing an arsenic atom, such as 4-hydroxy-3-nitrobenzenearsonic acid.

Two types of organic arsenic commonly found in seafood and known as "fish arsenic" are aresenobetaine and arsenocholine. Arsenocholine is more toxic than arsenobetaine, but both are generally relatively safe for humans. Two other types of organic arsenic, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), are commonly found in fruits, vegetables, and grains.

According to the American Cancer Society (ACS), the Environmental Protection Agency (EPA), and the Centers for Disease Control (CDC) in the United States, organic arsenic compounds have not been classified as carcinogens after decades of research.

According to the U.S. Food and Drug Administration (FDA), organic arsenic compounds can only become toxic to the body after they are converted into inorganic arsenic. Therefore, generally speaking, all arsenic compounds tend to be toxic to varying degrees.

Source of arsenic pollution

Arsenic is a natural component of the Earth's crust and is widely distributed in the air, water, and soil. Humans are exposed to inorganic arsenic through contaminated drinking water and food, inhaling fumes, vehicle exhaust, chemicals, and smoking. Chronic arsenic exposure causes various skin lesions and characteristic skin cancers.

The toxicity of arsenic

Acute arsenic poisoning causes vomiting, abdominal pain, and diarrhea. This is followed by numbness and itching of the skin and limbs, muscle cramps, and death in severe cases.

Prolonged exposure to arsenic causes skin damage such as changes in pigmentation, keratinization of the palms and soles, and eventually skin cancer. Besides skin cancer, arsenic can also cause bladder and lung cancer. The International Agency for Research on Cancer (IARC) has classified arsenic compounds, particularly arsenic contamination in drinking water, as carcinogenic to humans.

Long-term exposure to arsenic can also cause neurological disorders, diabetes, lung disease, and cardiovascular disease, including myocardial infarction, and complications in pregnant women and newborns.

According to Dan Tri