The popular Halloween costume trend that could make you blind. (Yikes.)

Halloween’s coming up and you might have started thinking about a costume to wear to that party/Stranger Things marathon you’re going to.

But if that costume includes novelty contact lenses like zombie or cat eyes, you might want to reconsider.

That’s because cosmetic contact lenses have been linked to bacteria that could cause infections and even blindness, Optometry Australia has warned.

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“This Halloween we don’t want to hear of yet another report of a young person suffering vision impairment caused by novelty lenses,” optometrist Luke Arundel said.

A recent US report published in the Journal of Forensic Science showed costume contact lenses had high rates of microbial contamination which can lead to infections, conjunctivitis and even permanent visual impairment and blindness.

Staggeringly, 60 per cent of suspected counterfeit lenses and 27 per cent of the authentic cosmetic contact lenses were contaminated – straight out of the packet. Meanwhile, three per cent of prescribed contact lenses were contaminated.

Optometry Australia pointed to another study that showed chemicals such as chlorine could also seep from the contacts and cause eye complications.

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I don’t know about you, but those $20 devil red contact lenses that sounded like a great deal 10 minutes ago… not so much anymore.

Arundel, Optometry Australia’s resident optometrist, urged consumers to think about contact lenses as medical devices, not costumes.

“It is essential they be purchased from an optometrist who will measure each eye to properly fit the lenses and evaluate how the eye responds to contact lens wear using a microscope,” Arundel said.

“Not only do optometrists ensure contact lenses fit the wearer properly, they also instruct on appropriate insertion and removal techniques and correct contact lens care to minimise the risk of irreversible eye damage.

“There are many prescription cosmetic or decorative contact lenses available through optometrists that are safe when properly prescribed and monitored by an eye care professional.”

Arundel said it was “scary” for him to think about how available the costume eye contacts were online, saying it is only through a dangerous legal loophole that it was so easy for people to purchase contact lenses without a prescription.

“It’s so easy for young people to obtain novelty contact lenses online, but the risk of infection is real and the consequences can be devastating.”

Yeah, we think we’ll just stick to a witch’s hat and a broom, thank you very much.

Find an optometrist in your local area at goodvisionforlife.com.au.