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Repellent? Famous Trick on Social Media Can Cause Risks, Deformations, and Even Worsen the Appearance of Plastic. Learn What Science Says.
A trick that went viral on social media, using insect repellent to clean car headlights, may cause more harm than good. The technique, which seems magical at first glance, promises to brighten old headlights and provide instant shine.
However, experts warn that the effect is superficial and, in the long run, can lead to deformations, scratches, and permanent deterioration.
The secret behind the instant shine lies in DEET, a chemical compound found in repellents that acts as a solvent on plastic.
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The Repellent Trick and the Car Headlight: What Really Happens?
Using repellent on car headlights has become a popular practice in videos and online tutorials. In just a few seconds, the product seems to remove dirt and restore transparency to the lenses. But what looks like a miracle has a chemical explanation.
The active ingredient in most repellents is DEET (diethyl-meta-toluamide). This compound is a potent solvent, designed to mask the scent of human skin, confusing the sensors of insects.
However, on the plastic of headlights, it dissolves the surface layer, softening the material.
Why the Effect is Only Temporary — and Dangerous
Indeed, DEET can remove visible dirt and accumulated oxidation, making headlights seemingly cleaner. However, what is being removed is part of the protection of the material itself.
After the use of repellent, the plastic can become sticky, pliable, and even cloudy over time.
In older headlights, the damage can be even more severe, leading to irreversible deformations. Additionally, continuous exposure to sunlight and the heat from the engine accelerates this wear.
New Headlights Also Face Risks with the Use of Repellent
Even in brand new cars, applying repellent to headlights can be risky. In newer models, the protective layer of the lens is more resistant, but still vulnerable to the corrosive effect of DEET.
If someone insists on the technique, the recommendation is to apply the product with a soft cloth, never spraying directly on the headlight.
Still, experts do not recommend frequent use, as the cumulative effects are unpredictable.
Is There Any Safe Product to Restore Headlight Shine?
For those who notice oxidation or cloudiness even after applying the repellent, an alternative is to use orange oil, which can be found in automotive product stores. The oil does not repair the damage but can temporarily restore the shine.
The safest solution, however, is to seek specific headlight polishing products, designed to clean without harming the material.
Specialized shops offer this type of service with long-lasting results and without the risk of deformation.
The Cheap Solution That Turns Expensive: Risks for the Car and the Wallet
Resorting to homemade tricks like using repellent on car headlights may seem advantageous at first glance. But the accumulated damage creates losses in the medium term.
Replacing a damaged headlight can be costly, especially in more modern vehicles.
Additionally, cloudy and deformed headlights compromise visibility at night and in rainy conditions, increasing the risk of accidents. Therefore, it is always better to opt for safe methods recommended by manufacturers.
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