Image copyright Getty Images Image caption Fans may be trying to recreate the look seen in the Twilight films

Fans of the Twilight film series have been warned that they could be putting their sight at risk by sharing cosmetic contact lenses bought online.

Cosmetic lenses are available to buy on the internet, in novelty stores or at market stalls, close to Hallowe'en.

Trading standards officers said the law stated that lenses should be sold with an optician or medic present.

Youngsters buying the lenses may wish to recreate the look of the Twilight films and Vampire Diaries TV show.

Cosmetic lenses are used to change the colour of the eye, and are also known as plano or zero-powered lenses.

Trading standards officers and health experts say young people are known to share them, leading to an increased risk of corneal ulcers and infections.

Alistair Bridge, director of strategy at the General Optical Council said: "Opticians make sure that contact lenses fit properly and that wearers receive expert advice on how to wear and store them safely.

"They will also offer important advice such as not to sleep in contact lenses and to never share or swap lenses, which can spread eye disease."

Leon Livermore, Chartered Trading Standards Institute chief executive, said: "Cosmetic contact lenses are often made and distributed on a one size fits all basis and not tailored to the wearer's needs which can increase the risk of eye health issues."

"We would advise against buying products like these online or from retailers as without professional supervision there are more likely to be health concerns for the individual."