Chocolate or copper brown post moem staining is seen in all of the following causes of death, except:
Nitrates, Potassium chlorate, Potassium bicarbonate, Aniline, all produce chocolate or copper brown post-moem staining. Clostridium perfingence causes bronze pigmentation in septic aboion.
Nitrates
Aniline dyes
Clostridium perfringence
Potassium chlorate