Superfund Research Program

September 2025

Paper of the Month

Biological markers found in urine may indicate uranium accumulation in kidneys, according to a study by the Columbia University SRP Center.

Natural uranium exists primarily as two isotopes, uranium 238 and uranium 235. The researchers examined whether changes in the ratio of uranium 238 to uranium 235 could be used as a biomarker to assess uranium accumulation in the body. They found that the kidneys and bones were enriched in uranium 235, whereas urine was enriched in uranium 238.

The results suggest that uranium 238 in urine could serve as an accurate, noninvasive biomarker for uranium accumulation in the kidneys. According to the authors, the findings could help improve early detection of kidney problems linked to chronic uranium exposure.

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