Many soft contact lenses in US made up of PFAS, research suggests

Testing of 18 popular kinds of contact lenses found extremely high levels of organic fluorine, a marker of ‘forever chemicals’

Many soft contact lenses in the US are largely made up of compounds called fluoropolymers that are by definition PFAS "forever chemicals", new research suggests.

Testing of 18 popular kinds of contact lenses found extremely high levels of organic fluorine, a marker of PFAS, in each.

"You could consider [the lenses] almost pure PFAS," said Scott Belcher, a North Carolina State University researcher and scientific adviser on the contact lens testing.

PFAS are a class of about 14,000 chemicals typically used to make thousands of consumer products resist water, stains and heat. They are called "forever chemicals" because they do not naturally break down, and they are linked to cancer, fetal complications, liver disease, kidney disease, autoimmune disorders and other serious health issues.

The testing, commissioned by the Mamavation and Environmental Health News public health blogs and conducted at an Environmental Protection Agency-certified lab, looked for organic fluorine in lenses made by Acuvue, Alcon and Coopervision. It found the chemical at levels between 105 parts per million (ppm) to 20,700ppm.

The chemistry is complex and there may be some other ingredients in the lenses, but the readings suggest fluoropolymers. Fluoropolymer PFAS in this form are essentially a soft plastic material and are used for disposable, soft lenses because "they have the properties that your eyes want", Belcher said.

"It wants to get oxygen and doesn't want bacteria to grow like crazy, and it wants lenses to be smooth and comfortable," he added.

It is difficult to say what kind of health impacts this level of eye exposure to the chemicals may have because no studies on how the eyes absorb PFAS from lenses have been done. However, PFAS are absorbed through the dermis and are highly mobile compounds, so it's possible that eyes do absorb some level of the chemicals, though fluoropolymers are generally a less mobile kind of PFAS.

But PFAS also break down into different types of PFAS once in the environment, so it is possible that the polymers turn into dangerous forms of the chemicals once in the eye or contact packaging, but no studies have been done. Chinese researchers in 2020 linked high PFAS exposure to several eye diseases.

The three lenses with the highest amounts of organic fluorine were Alcon Air Optix (No Hydraglide) for Astigmatism (20,000ppm), Alcon Air Optix Colors with Smartshield Technology (20,700ppm) and Alcon Total30 Contact Lenses for Daily Wear (20,400ppm).

Among the lowest levels included Acuvue Oasys with Hydraclear Plus with UV Blocking (113ppm) and Alcon Dailies Total One-Day Water Gradient for Astigmatism (106ppm).

Coopervision, Alcon, and Johnson and Johnson, which owns Acuvue, did not immediately respond to requests for comment.

Companies rarely disclose when they use PFAS because the federal government allows them to claim it as a trade secret. The chemicals are also so widely used that they can be unintentionally added to products throughout the supply chain. Independent and academic researchers in recent years have found them in a range of products from toilet paper to plastic food containers to fruit juice.

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Congress, the EPA, and the Food and Drug Administration have done little to curb the use of PFAS in products, and though some states have begun banning the chemicals’ use in cosmetics and other consumer goods, no state-level laws address contact lenses.

However, Maine recently passed a ban on all non-essential uses of PFAS that will go into effect in 2030, and the EU is considering a similar blanket restriction.

The use of PFAS in contact lenses, which are essentially a medical device, Blecher said, is a case study in the debate over what may or may not constitute an "essential use".

There's little that consumers can do to protect themselves beyond wearing glasses or having a conversation with their doctor about possible alternatives, Belcher said. He added that his contacts contain the chemicals but he has not made any changes since learning of the test results.

"There are alternatives that may have some downsides and upsides, but that's a discussion to have with your doctor," he said.