Presumptive Identification of Nitrite by Griess Reagent Test Strips - Case reports of fatal poisoning with sodium nitrite.The intentional ingestion of sodium nitrite causes toxicity by inducing methemoglobinemia which can lead to cyanosis, hypotension, and death. 
Griess Reagent Test Strips
In this study, a common Griess reagent color test (MQuant™ Nitrite Test Strips) was used as a presumptive method in cases where the ingestion of sodium nitrite was suspected. 
MQuant™ Nitrite Test Strips