Why Do Oxidants Appear in Urine?

Oxidants, or oxidizing agents, appear in the urine as a result of deliberate adulteration of a clinical urine sample, according to the American Association for Clinical Chemistry. Strong chemical oxidizing agents are not produced by the human body, so their detection in urine is indicative of contamination or adulteration. The purpose of oxidizing agents is to react with drug metabolites so that they cannot be detected on a urine drug screen, states Home Health Testing.

Common oxidizing agents added to urine include bleach (sodium hypochlorite), hydrogen peroxide and pyridinium chlorochromate. Some are packaged and sold specifically for the purpose of beating drug tests. Bleach and hydrogen peroxide are household substances that cause a false negative on a urine drug screen by oxidizing drug metabolites, as reported by AboutDrugTesting.org. Their presence in urine indicates the sample has been tampered with.

Pyridinium chlorochromate is a strong chemical oxidizing reagent used in scientific research and industrial chemical manufacturing. PCC is generally used to mask the presence of marijuana metabolites in the urine, according to the American Journal of Clinical Pathology. Finally, high concentrations of nitrites in the urine may also indicate urine adulteration. Ingestion of high doses of sodium nitrite or potassium nitrite (both oxidizers) can mask the presence of excreted drug metabolites.