Researchers have shown that sunflower seeds are frequently contaminated with a toxin which has the potential to cause live cancer.

In the study published in the journal PLoS ONE, the team of scientists documented frequent occurrence of aflatoxin -- a toxin produced by Aspergillus molds that commonly infect corn, peanuts, pistachios and almonds -- in sunflower seeds and their products.  The study was conducted in Tanzania, but the problem is by no means isolated there, the researchers said.

Chronic exposure to aflatoxin causes an estimated 25,000-155,000 deaths worldwide each year, from corn and peanuts alone.  Since it is one of the most potent liver carcinogens known, the research to detect and limit its presence in sunflower seeds and their products could help save lives and reduce liver disease in areas where sunflowers and their byproducts are consumed, said study co-author Gale Strasburg, Professor at Michigan State University in the US. 

"These high aflatoxin levels, in a commodity frequently consumed by the Tanzanian population, indicate that local authorities must implement interventions to prevent and control aflatoxin contamination along the sunflower commodity value chain, to enhance food and feed safety in Tanzania," he said. 

"Follow-up research is needed to determine intake rates of sunflower seed products in humans and animals, to inform exposure assessments and to better understand the role of sunflower seeds and cakes as a dietary aflatoxin source," Strasburg added.