Bromine

Carl Jacob Löwig and Antoine Balard both discovered bromine independently, in 1825 and 1826, respectively. Löwig found the element in a sample of mineral spring water from his hometown of Bad Kreuznach, Germany. Publication of his findings was delayed, however, and in the meantime, Balard found bromine in seaweed from the salt marshes of Montpellier, France.

Balard originally named his discovery mulide, from the Latin word for “brine,” reflecting the salty marshes of the seaweed. He later changed the name to bromide, from the Latin for “stench," for similar reasons.

Even though bromine was discovered in the 1820s, it wasn’t produced in large quantities until 1858, when large salt deposits were found in Stassfurt, Germany. These salt deposits made it easier to produce bromine as a by-product of potash, and its production started to pick up.

Bromine was first used for early photography—making the light-sensitive silver layer needed for daguerreotypes. The process originally relied on iodine, but neighboring bromine proved to be better at increasing light sensitivity of photographic plates, helping to create sharper images.

By the American Civil War, doctors were using a bromine solution to treat gangrene, even before we fully understood how infections worked. Later, bromine compounds had more medical uses, like being used in sedatives and to treat seizures, but eventually, other drugs replaced them.

Bromine is the only nonmetallic liquid element and one of two elements (the other being the metal mercury) that is a liquid at standard temperature and pressure. It readily vaporizes to a stinky, reddish-brown gas at room temperature that can irritate the eyes and throat. It is also readily soluble in water or carbon disulfide, forming a red solution. When spilled on the skin, it produces painful sores. Bromine presents a serious health hazard, and maximum safety precautions should be taken when handling it.

Before lead was banned in gasoline, much of the bromine in the United States was used in the production of ethylene dibromide, a lead scavenger used in antiknock compounds, which prevent fuel from combusting in the engine at the wrong time.

Bromide salts were once commonly used as a sedative before shorter-acting drugs were available. They remain pharmaceutically useful in antiepileptics.

Bromine is also used today in water purification compounds, dyes, sanitizers, and photographic film, much like it's first commercial use in daguerreotypes.

Bromine unites readily with many elements and can take on a bleaching action, meaning it can decolorize other substances. The compounds potassium bromide and sodium bromide were used medically in the late 19th and early 20th centuries. During World War I, bromide compounds were used as poison gas.

Organic bromine compounds are also an important component of fire retardants, and more than 50% of bromine use worldwide is for this application.

Because it is so reactive, bromine does not occur as a free element in nature. Like other elements in the halogen group, it can be extracted from halide salts. It is commercially sourced from saltwater evaporation ponds as well as seawater, which contains about 85 ppm of bromine.