It’s a mainstay of detective fiction; it’s a naturally occurring element in the earth’s crust, from which it spreads through water, soil and air; it’s useful in many ways, but toxic in even more ways. Arsenic is a very versatile element, and it has been known to humans for millennia. The term itself comes from the Arabic word al zarniqa, meaning “yellow”.
Arsenic is a metalloid that can occur as a pure crystal, as well as in various minerals. Inorganic arsenic is extremely toxic, more so than organic arsenic compounds.
The most common arsenic allotropes (forms in which an element can exist) are gray, yellow, and black.
When exposed to humidity, arsenic turns golden-bronze and black.
For a number of centuries, arsenic was widely used in medicine, for instance as stimulants or to treat syphilis, leukemia and other cancers, psoriasis etc. In recent years, arsenic-74 is sometimes used in PET scans instead of iodine-124 to help detect the presence of tumors.
Other products in which arsenic was or is used include:
Arsenic is naturally present in the environment and can be released through volcanic explosions or contaminated groundwater in areas with high concentrations of arsenic.
Symptoms of arsenic poisoning include:
If ingested – the most specific effects relates to skin pattern changes and cancer (including liver, kidney, bladder, prostate and lung cancer); also at lower doses, the digestive system may be affected with symptoms such as nausea vomiting, stomach irritation, diarrhea, damage to blood vessels.
If inhaled – skin changes; irritation of throat and lungs, circulatory problems, nervous system disorders