It was sodium chromate, a well-known carcinogen that, according to the National Institutes of Health, can harm the respiratory tract, stomach, liver, kidneys and immune system.

Sodium Chromate Cr-51 Injection is a radiopharmaceutical used in diagnostic testing to determine red blood cell (RBC) volume or mass, the study of RBC survival time, and evaluation of blood loss.

Viability of Ehrlich Ascites Tumour Cells exposed to Sodium Chromate labelled with Chromium-51 P. C. VINCENT 1 na1 Nature volume 196 , pages 179–180 ( 1962 ) Cite this article ...