Selenium Urine Test in California

What this test measures

Selenium is a trace element obtained mainly from food. The body uses it to build selenoproteins, including glutathione peroxidase, which helps protect cells from oxidative damage. Because both too little and too much selenium can affect health, testing is used selectively. A urine selenium measurement reflects recent intake and excretion, making it useful when dietary sources are uncertain or when exposure is a concern.

The sample is a urine collection, typically a spot or timed sample, analyzed for selenium concentration. Urine is one of the main routes by which the body removes selenium, so the level can indicate how much of the mineral is circulating. Results are usually reported as micrograms per liter or per gram of creatinine, and laboratories may adjust for sample dilution using creatinine.

This test may be ordered for people with suspected poor selenium intake, those who rely on long-term intravenous nutrition, or workers with possible industrial exposure to selenium compounds. It is an educational tool and not a diagnosis. A qualified healthcare provider interprets the level in the context of diet, supplements, medications, and overall health.