Why do Tervis cups get cloudy?

Ah, the infamous Tervis haze. It's a frustrating phenomenon that many Tervis cup owners have encountered at some point. You know the one – that weird, rough stain that fogs up the cup, making it look less than appealing. But have you ever wondered why this happens?

After doing some research, I discovered that the Tervis haze is often caused by sunscreen. you heard that right – sunscreen. It turns out that sunscreen can actually cause a chemical reaction with the Tervis plastic, resulting in this cloudy appearance.

Now, let me walk you through the science behind this. Tervis cups are typically made from a type of plastic called polypropylene. This material is known for its durability and ability to withstand high temperatures. However, it is not completely impervious to certain chemicals, such as those found in sunscreen.

When sunscreen comes into contact with the Tervis plastic, it can cause a reaction that leads to the formation of a hazy film. This film is not easily removable and can be quite stubborn. It often feels rough to the touch and can be difficult to clean, even with vigorous scrubbing.

So, how does this all tie back to the scenario you mentioned? Well, it's quite possible that the person who bought the Tervis bottle in question applied sunscreen to their skin and then took a swig from the same hand. This would have transferred some of the sunscreen onto the cup, setting off the chemical reaction that resulted in the Tervis haze.

Now, it's worth noting that not all sunscreens will have this effect on Tervis cups. The specific ingredients in the sunscreen, as well as the concentration and frequency of application, can all play a role in whether or not the Tervis haze occurs. Additionally, other factors such as heat and exposure to sunlight can exacerbate the issue.