A metal compound commonly found in consumer products and sunscreens lotions could potentially cause cancer.
Zinc oxide is used to absorb harmful ultra violet light. But when it is turned into nano-sized particles, they are able to enter human cells and may damage the user's DNA.
This activates a protein called p53, whose duty is to prevent damaged cells from multiplying and becoming cancerous, says a new study led by Joachim Loo, Ng Kee Woei and David Leong, assistant professors at the Nanyang Technological University (NTU) here.
However, cells that lack p53 or do not produce enough functional p53 may instead develop into cancerous cells when they come into contact with zinc oxide nanoparticles, the journal Biomaterials reports.
"Currently there is a lack of information about the risks of the nanomaterials used in consumer products... This study points to the need for further research in this area," said Loo, according to an NTU statement.
Nanotoxicology studies materials to see if they are toxic or harmful when they are turned into nano-sized particles. This is because nanomaterials usually have very different properties when compared to the materials of a larger size.
"From our studies, we found that nanoparticles can also increase stress levels in cells, cause inflammation or simply kill cells," said Woei.
Loo said the team is also studying how nanomaterials can be "re-designed" to pose a lesser risk to humans, yet still possess the desired beneficial properties.