Laboratory dust copper

Butters, "Naval Pyrotechnic Formulas , NOLM (Naval Ordnance Laboratory Memorandum) 9292 (1947), Washington 25, DC (Naval Signal Cartridge MK3, Formula 2 Copper dust 1.9, Ba nitrate 67.2, hexachlorobenzene 14.7 Mg powder 14.7 linseed oil 1.5%. Burns 5 sec with green light at altitude 250 ft)... 

Copper Powder.—100 gms. of crystallised copper sulphate are dissolved in 350 gms. of water in a beaker, to which is attached a mechanical agitator. After cooling to laboratory temperature, the stirrer is set in motion, and 35 gms. (or more if necessary) of good quality zinc dust are gradually added until the solution is decolorised. The precipitated copper... 

The dust and powder preparations of copper compounds are irritating to the skin, respiratory tract, and particularly to the eyes. The soluble copper salts (such as the sulfate and acetate) are corrosive to mucous membranes and the cornea. Limited solubility and absorption probably account for generally low systemic toxicities of most compounds. The more absorbable organic copper compounds exhibit the greatest systemic toxicity in laboratory animals. 

The prime concerns in determining copper concentration are contamination and loss. The potential sources of contamination are the impurities in reagents, impurities on laboratory apparatus that the sample touches, and the dust in the laboratory. Consequently, particular attention should be given to the collection and treatment of the sample prior to analysis. The sample bottle should be thoroughly washed with detergent and tap water next it should be successively rinsed with 10% hydrochloric or nitric acid and then three times with distilled or demineralized water [26]. 

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