The Measure-iT™ Lead and Cadmium Assay Kit has a linear range of 5 -200 nM of either lead or cadmium. This assay range translates to a detection limit of 1 ppb lead in a 200 µL well volume or 0.6 ppB cadium. This lead assay or cadmium assay is useful for many applications including environmental testing for lead contamination and lead sensing as well as cadium sensing and cadium contamination. The assay is performed at room temperature, and the signal is stable for at least 30 minutes. Cross-contamination by many metals is well tolerated (see PIS for details.)