Gun bluing

Currently, there are no antidotes of choice for selenium toxicity. Ethylenediaminetetraacetic acid and BAL (British antilewisite 2,3-dimercaptopropanol) should not be used because they may enhance selenium toxicity. Treatment is symptomatic (e.g., cardiopulmonary). Often, supplemental oxygen is needed. Corrosive selenious acid (in gun-bluing solution) should be treated similar to other agents that cause esophageal burns. 

Acute overdose. The oral mean lethal dose (MLD) of selenite salts in the dog is about 4 mg/kg. Ingestion of 1-5 mg/kg sodium selenite in five adults caused moderate reversible toxicity. Ingestion of as little as 15 mL of gun bluing solution (2% selenious acid) has been fatal. 

Selenious acid (hydrogen selenite) CASRN 7783-00-8 White powder encountered as 2% solution in gun bluing Ingestion of as little as 15 mL of a 2% solution was reported fatal in a child. 

The parts should now be blued or finished in whatever fashion that you desire. Hot nitrate bluing is described in Volume One of Home Workshop Guns for Defense and Resistance and instructions on how to apply a rust blue are contained in Volume Two. 

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