Sunscreen might protect your skin from UV rays but it is actually bad for your health as a new study has found that nano particles present in it are toxic.
Researchers at the Department of Pharmacology and Toxicology of University of Utah found evidence that sunscreens contain nano particles of zinc oxide,used to prevent the damaging effects of sunlight,that can harm colon cells and may be toxic if accidentally eaten.
They said that particle size affects the toxicity of zinc oxide that is widely used in sunscreens and particles smaller than 100 nano metres are slightly more toxic to colon cells than conventional zinc oxide,Chemical Research in Toxicology journal said.
“There is ongoing concern about the potential toxicity of nano particles of various materials,which may have different physical and chemical properties than larger particles. Barely 1/50,000 the width of a human hair,nano particles are used in foods,cosmetics and other consumer products,” lead author Philip Moos said.
He said,”Some sunscreens contain nano particles of zinc oxide and unintended exposure to nano-sized zinc oxide from children accidentally eating sunscreen products is a typical public concern,motivating the study of the effects of nano materials in the colon”.
The study showed that nano particles were twice as toxic to the cells as the larger particles. Although the nominal particle size was 1,000 times larger,the conventional zinc oxide contained a wide range of particle sizes and included material small enough to be considered as nano particles.
The concentration of nano particles that was toxic to the colon cells was equivalent to eating 2 grams of sunscreen about 0.1 ounce.
This study used isolated cells to study biochemical effects and did not consider the changes to particles during passage through the digestive tract.