No-fog sprays for glasses work, but can be harmful

To prevent your glasses from fogging up, you need to make sure your face mask fits snugly at the upper edge and is tucked well under the glasses. — dpa

As anyone who has ever worn glasses and a face mask at the same time will know, fogged-up lenses are a constant problem. Anti-fogging solutions promise help, but consumer experts are warning that some contain harmful substances.

With fogged-up glasses now an everyday nuisance during the pandemic, more and more shops are selling these special sprays with a moisture-repellent effect supposed to prevent moisture fogging up your glasses.

But Germany’s Consumer Advice Centre of North Rhine-Westphalia (VZ NRW) advises spectacle wearers not to use any sprays, gels or cloths which contain so-called PFASs (per- and polyfluoroalkyl substances).

These compounds are harmful to human health and the environment because they don’t break down easily.

This means they accumulate in the human body, and in plants and animals, potentially leading to cancer, immune system problems or increased cholesterol.

You’ll often find no information about these active ingredients on the product or the packaging, and where this is the case, these solutions should not be used.

If ingredients are listed look out for words that include “-fluor” or “-fluoro” because these indicate that PFASs are probably present.

Consumers should also check whether “hydrophobic” or “water-repellent” are mentioned, as these terms could also be signs of PFASs.

There are a number of relatively simple tricks that help prevent glass lenses fogging, without the need to resort to chemicals.

The best thing for people who wear glasses is to make sure that their face mask fits tightly at the upper edge and that your glasses sit over the mask.

A very thin film of washing-up liquid or soap on the lenses can also protect against fogging to a certain extent.

Before doing so, however, you may want to ask your optician whether this is possible with your particular lenses. – dpa