(NaturalNews) Sunscreens made with nanoparticles may cause serious bodily harm, a report from Friends of the Earth has warned.

"Consumers need to know that manufactured nanoscale zinc and titanium oxides are not the only choice and are not necessarily the most effective or safest choice for sun protection," the report reads.

Many sunscreens now contain nanoscale particles of titanium dioxide or zinc oxide, roughly 100,000 times smaller than the width of a human hair. The only reason for using nanotechnology is to make the sunscreens less oily and easier to rub into the skin.

Although titanium dioxide and zinc oxide have long been used in sunscreens and are considered relatively safe, the normal rules no longer apply to matter on the nano scale.