Recently we learned of a toxic pollution from an old Antimony mine which appears to have killed fish for dozens of kilometres along the Macleay River in northern NSW. The state government said there was no increased health risk because the contamination, east of Armidale, was diluted, but nevertheless alerted residents along the river as a precaution.
Antimony is a semi-metallic chemical that can exist in the metallic form as a bright, silvery, hard and brittle element; and the non-metallic form as a grey powder making up about 0.00002% of the earth's crust.
Humans have made use of antimony compounds for millennia. The mineral stibnite (Sb2S3) was used in Egyptian cosmetics four or five thousand years ago as an eyeliner. In more recent times, it’s used to make certain types of semiconductor devices, such as diodes and infrared detectors.
Antimony alloys are also used in batteries, low friction metals, type metal and cable sheathing, among other products. Antimony compounds are used to make flame-proofing materials, paints, ceramic enamels, glass and pottery.
However, Antimony and many of its compounds are very toxic, and the effects of antimony poisoning are similar to arsenic poisoning. Inhalation of antimony dust is harmful and in certain cases may be fatal; in small doses, antimony causes headaches, dizziness, and possibly depression. Larger doses such as prolonged skin contact may cause dermatitis; otherwise it can damage the kidneys and the liver, causing violent and frequent vomiting, and will lead to death in a few days.
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