Open a vial of dark red liquid and an unbearable stench instantly fills the room. This is bromine — one of only two elements that remain liquid at room temperature. The dense reddish-brown fluid constantly fumes, releasing toxic orange vapors that attack the eyes and lungs.
Yet behind this menacing appearance hides a remarkably useful element. Bromine protects our homes from fire as the backbone of flame retardants. It purifies swimming pool water. Without it, classical photography would never have existed — silver bromide captured the world's most important moments for over 150 years.
Free bromine barely exists in nature — it is far too reactive. But dissolved in seawater, there is plenty: the world's oceans hold roughly 65 million tons. The richest deposits sit in the Dead Sea brines and underground waters of Arkansas, USA. That is where most industrial bromine is extracted.
Today, over 40% of produced bromine goes into flame retardants — substances that slow down combustion in plastics, textiles, and electronics. The rest serves pharmaceuticals, water treatment, and chemical synthesis.
Bromine is an extremely corrosive and toxic substance. Liquid bromine causes deep chemical burns on contact with skin that heal very slowly. Its vapors irritate the eyes, damage the respiratory tract, and can trigger pulmonary edema. Concentrations above 10 ppm in air are life-threatening. Handling bromine requires a fume hood, full protective suit, safety goggles, and chemical-resistant gloves.
Bromine is the only nonmetal that is liquid at room temperature. Among all 118 elements, only bromine and mercury (a metal) share this property.
The name 'bromine' comes from the Ancient Greek 'βρῶμος' (bromos) meaning 'stench'. 19th-century chemists named it after its unbearable smell, detectable even in tiny concentrations.
Silver bromide (AgBr) was the foundation of classical photography. AgBr crystals darken when exposed to light — this principle powered every roll of film for over 150 years.
The Dead Sea contains 80 times more bromine than ordinary seawater. Israel and Jordan are among the world's largest bromine producers thanks to this natural reservoir.
Bromine was discovered by 24-year-old student Antoine Balard in 1826. He was studying seaweed and found an unknown element in the leftover brine.
During World War I, bromine was used to produce xylyl bromide — a tear gas deployed as a chemical weapon on the battlefields of Europe.
| Isotope | Mass (u) | Abundance | Half-life | Decay |
|---|---|---|---|---|
79Br | 78.918337 | 50.69% | stable | — |
81Br | 80.916291 | 49.31% | stable | — |
Treatment of seawater brine