Inorganic Arsenic Mass Concentration in Urine

Why This Test Matters

Arsenic is a naturally occurring element that can be harmful in high amounts. Inorganic arsenic is particularly toxic and can cause serious health issues if present in your body. This test checks for recent exposure by measuring arsenic in your urine over a full day, which reflects how much your body is processing.

What to Expect Before the Test

No special preparation is needed for this test. You’ll provide a 24-hour urine collection, starting after your first morning urine void and ending with your urine from the next morning. Collect all urine in a container, keeping it refrigerated if possible. Bring the full collection to your lab appointment.

What the Results Mean

Higher-than-normal levels may indicate recent exposure to arsenic, possibly from contaminated drinking water, diet, or environmental sources. Very high levels could signal acute poisoning. Your doctor will interpret results in the context of your medical history and other tests.

Common Causes of Abnormal Results

Elevated arsenic levels can stem from drinking well water contaminated with arsenic, eating foods grown in arsenic-rich soil, or occupational exposure (e.g., mining, electronics manufacturing). Chronic low-level exposure may also contribute over time.