Industrial Arsenic Poisoning.—In the extraction of arsenic and preparation of arsenious acid danger is present. But reliable accounts in literature of poisoning among those engaged in arsenic works are wanting.
Those engaged in roasting operations and packing suffer much from skin affections. Similar poisoning is reported in the smelting of other arsenical ores—nickel, cobalt, lead, copper, iron, and silver, from arsenic compounds present in the fumes. This is especially the case in the smelting of tin, which generally contains arsenical pyrites.
Danger is present also in unhairing (i.e. removing the wool from sheep skins), since the skins imported from Buenos Aires and Monte Video are treated with a preservative which, in addition to sodium nitrate, soda, and potash, contains generally arsenious acid.
In tanneries a mixture of arsenic sulphide (realgar) and lime is used for unhairing. Arsenic is used also for preserving and stuffing animal furs; but although affections of the skin are described I cannot find reference to arsenical poisoning.
The inspector for East London in 1905 refers to severe eczematous eruptions on face, neck, and hands, affecting workers in a sheep dip works—mainly in the packing of the light powder in packets.
Formerly the use of arsenic in the manufacture of colours was great, especially of emerald (Schweinfurter) green. This is made by dissolving arsenious acid in potash with addition of acetate of copper. Drying and grinding the material constitute the main danger. Scheele’s green is another arsenical colour.
Use of arsenic colours is becoming less and less. But in colour printing of paper and colouring of chalk they are still employed. They are used, too, as mordants in dyeing, but cases of poisoning from these sources in recent years are not to be found.
The dust in many glass works contains, it is stated, as much as 1·5 per cent of white arsenic.
Despite the numerous opportunities for arsenical poisoning in industries it is rare or, at any rate, is only rarely reported.
Arseniuretted Hydrogen Poisoning.—Industrial poisoning from arseniuretted hydrogen is caused mostly by inhalation of the gases developed by the action on one another of acids and metals which contain arsenic. Hydrogen gas as usually prepared for filling balloons gives occasion for poisoning.