Cobalt is an essential trace element and forms part of the active site
of Vitamin B12. The amount of cobalt required in the human body is
very small and it contains only about 1 mg. Cobalt salts in small
doses have been found to be effective in correcting mineral
deficiencies in certain animals. But in large doses it is carcinogenic.
The radioactive isotope Cobalt 60 is sometimes used in some
countries to irradiate food to preserve it. There are no established
criteria limits for cobalt in medicinal plants[37]. Cobalt was not
detected in this plant extract.