Counterfeit contact lenses sold through a woman's Facebook page were "extremely dangerous" and a "disaster waiting to happen", a court has been told.
The items from Alluring Lenses - run by Zahra Gillani - were analysed and found to be "defective", prosecutors said.
She ordered them via a Chinese-owned website, Alibaba, which the jury heard was "notorious" for fake products.
Appearing at Newcastle Crown Court, she denies three counts of selling and one count of possessing counterfeit goods.
The 31-year-old said she believed the lenses she sold as Freshlook Colorblends to be genuine along with the accompanying solution.
The court was told investigators searched Ms Gillani's property at Gowland Avenue, Newcastle, in July 2018 and found packets of lenses, cardboard boxes and sticky labels.
Analysis showed some of the lenses had defects such as air bubbles.
Prosecutor Julian Goode read a statement from Prof Sunil Shah, president of the British Contact Lens Association, who warned counterfeit products could result in the wearer losing an eye to infection.
The professor, who is also a consultant ophthalmologist in Birmingham, said non-sterilised lenses carried an "immense" risk and were a "disaster waiting to happen".
"These were defective lenses in a defective broth. These lenses were extremely dangerous."
In another statement, investigator Christopher Adams, working on behalf of TM Eye Ltd, a private firm that targets counterfeiting, said a basic internet search would have revealed the Alibaba website could not be trusted.
"Alibaba sellers have been notorious for selling counterfeit items," he said.
Giving evidence, Ms Gillani said she had been unaware of the website before she looked for suppliers of coloured lenses in 2013 and decided to use Alibaba as it was the top result in her search engine.
She told the court she "assumed" sellers were legitimate and that she had no concerns about authenticity until the day her home was searched by investigators.
The jury heard Ms Gillani paid $2.35 (£1.75) per pair of lenses through Paypal from a contact she believed worked at the factory which manufactured Freshlook lenses.
She would then sell them for £15 per pair.
Ms Gillani, who previously worked in sales for pharmaceutical companies including Pfizer and Bayer, denied that she "must have known" the lenses were fake and said she "very often" wore them herself as well as giving them to friends and family.
The trial continues.