Sodium fluoroacetate

Sodium fluoroacetate, also known by its trade name as a mammal poison compound 1080, is an organofluorine chemical compound with the chemical formula FCH₂CO₂Na. It is the sodium salt of fluoroacetic acid, and contains sodium cations Na⁺ and fluoroacetate anions FCH₂CO−2. A colourless salt with a taste similar to table salt (sodium chloride), it is used under the name "1080" to kill small and medium mammals, including rodents. New Zealand has no endemic ground-based mammals and is the world's biggest user of 1080, particularly to kill introduced brushtail possums, often with aerial spraying.

Fluoroacetate occurs naturally in at least 40 plants in Australia, Brazil, and Africa. It is one of only five known organofluorine-containing natural products.

Gastrolobium is a genus of flowering plants in the family Fabaceae. This genus consists of over 100 species, and all but two are native to the southwest region of Western Australia, where they are known as "poison peas". Gastrolobium growing in southwestern Australia concentrate fluoroacetate from low-fluoride soils. Brushtail possums, bush rats, and western grey kangaroos native to this region are capable of safely eating plants containing fluoroacetate, but livestock and introduced species from elsewhere in Australia are highly susceptible to the poison, as are species introduced from outside Australia, such as the red fox. The fact that many Gastrolobium species also have high secondary toxicity to non-native carnivores is thought to have limited the ability of cats to establish populations in locations where the plants form a major part of the understorey vegetation.

The presence of Gastrolobium species in Western Australia has often forced farmers to 'scalp' their land, that is, remove the top soil and any poison pea seed which it may contain, and replace it with a new poison pea-free top soil sourced from elsewhere in which to sow crops. Similarly, after bushfires in north-western Queensland, cattlemen have to move livestock before the poisonous Gastrolobium grandiflorum emerges from the ashes.

The related compound potassium fluoroacetate occurs naturally as a defensive compound in at least 40 plant species in Australia, New Zealand, Brazil, and Africa. It was first identified in Dichapetalum cymosum, commonly known as gifblaar or poison leaf, by Marais in 1944. As early as 1904, colonists in Sierra Leone used extracts of Chailletia toxicaria, which also contains fluoroacetic acid or its salts, to poison rats. Several native Australian plant genera contain the toxin, including Gastrolobium, Gompholobium, Oxylobium, Nemcia, and Acacia. New Zealand's native Puha contains 1080 in very low concentrations.

X-ray crystallography confirms that solid sodium fluoroacetate is a salt with intact fluoroacetate anions interacting with Na⁺ via a network of Na-O bonds.

Sodium fluoroacetate can be produced by the reaction of fluoroacetic acid and a basic sodium salt, such as sodium carbonate and sodium hydroxide. However, it is industrially produced by treating sodium chloroacetate with potassium fluoride.

Sodium fluoroacetate is toxic to most obligate aerobic organisms, and highly toxic to mammals and insects. The oral dose of sodium fluoroacetate sufficient to be lethal in humans is 2–10 mg/kg.