Chlorophyll and chlorophyllin have been shown to reduce the activity of cancer causing agents in animals. These benefits were partially extended to humans where cholorphyllin reduced the excretion of aflatoxin, a fungal toxin linked to liver cancer. Researchers at Linus Pauling Institute in Orgeon conducted a crossover study to determine if this benefit is present in humans.
Protocols were repeated thrice for each volunteer. The study evaluated and found rapid human aflatoxin uptake and elimination from the body, through the kidneys. Chlorophyll and Chlorophyllin treatment each significantly restricted the absorption of aflatoxin. The results suggest that these two substances my limit the bioavailability of ingested aflatoxin in humans, as they do in animal models.
Source: http://www.ncbi.nlm.nih.gov/pubmed/19952359?dopt=Abstract