Miami Mold: Is Sunscreen Feeding Your Sinuses?

By Franklin Everett Shaw

August 4, 2025

Miami: Sunscreen, Sinuses, and the Mold Connection You Didn’t Know About

Think Miami, and you probably picture sun-drenched beaches, vibrant nightlife, and maybe the occasional alligator sighting. What you don’t picture is a hidden battle being waged in your sinuses, fueled by something you slather on to protect yourself from the sun. But for many Miami residents, the link between sunscreen, humidity, and sinus mold is a very real, and very unpleasant, reality.

The problem isn’t the sun itself, but rather the chemical cocktail in many sunscreens that, when combined with Miami’s unique climate, creates a perfect breeding ground for mold in your nasal passages. It’s a nasty little secret that dermatologists often overlook, and that many Miamians suffer from without realizing the root cause.

So, what’s the connection? It boils down to this: certain sunscreen ingredients, when washed off by sweat or ocean water, can become a food source for mold, particularly in the warm, humid environment that defines South Florida.

Let’s break down the specific culprits.

Oxybenzone and Octinoxate: These are common UV filters found in many chemical sunscreens. While effective at blocking the sun’s rays, they are also known endocrine disruptors and coral reef pollutants. But here’s the kicker: studies have shown that certain molds can metabolize these compounds. When you sweat these chemicals into your eyes and nose, or when they wash off into the ocean and then get aerosolized by the wind, they can provide a readily available food source for mold spores already present in your sinuses.
Emulsifiers and Stabilizers: Many sunscreens contain ingredients like acrylates copolymer, which help to keep the formula stable and prevent separation. These polymers, while generally considered safe for topical use, can also be broken down by certain types of mold. Again, the warm, humid environment of Miami accelerates this process.
Fragrances: Artificial fragrances are often added to sunscreens to make them more appealing. However, these fragrances can contain volatile organic compounds (VOCs) that can irritate the nasal passages and weaken the immune system, making you more susceptible to mold infections.

Now, let’s talk about Miami’s unique environment. The city’s high humidity and frequent rainfall create ideal conditions for mold growth, both indoors and outdoors. Mold spores are everywhere, and they’re constantly looking for a source of food and moisture to thrive. When sunscreen chemicals are introduced into this equation, it’s like throwing a mold party in your nose.

The symptoms of sinus mold infections can be varied and often mistaken for allergies or a common cold. These include:

Nasal congestion
Runny nose
Postnasal drip
Headaches
Facial pain
Fatigue
Sneezing
Itchy eyes

If you’re experiencing these symptoms, especially if they worsen after spending time outdoors or swimming in the ocean, it’s worth considering the possibility of a sunscreen-related mold issue.

So, what can you do to protect yourself? Here’s a step-by-step approach:

Choose Your Sunscreen Wisely: Opt for mineral sunscreens containing zinc oxide or titanium dioxide. These ingredients are less likely to be metabolized by mold. Look for fragrance-free formulas and avoid sunscreens containing oxybenzone, octinoxate, and acrylates copolymer. Badger Balm and Thinkbaby are two brands that consistently receive high ratings for their mineral sunscreen formulations.
Practice Mold-Resistant Nasal Hygiene: Regularly rinse your nasal passages with a saline solution. This helps to remove mold spores and sunscreen residue. Consider using a neti pot or a nasal spray containing xylitol, which has been shown to inhibit mold growth. Xlear is a popular brand of xylitol nasal spray.
Limit Exposure: While it’s impossible to avoid the sun entirely in Miami, try to limit your exposure during peak hours (10 am to 4 pm). Wear protective clothing, such as hats and long sleeves, and seek shade whenever possible.
Consider Diet: A diet high in sugar and processed foods can weaken your immune system and make you more susceptible to mold infections. Focus on eating whole, unprocessed foods, and consider adding antifungal foods like garlic, onions, and ginger to your diet.
Address Indoor Mold: If you suspect you have mold in your home, take steps to remediate it. This may involve hiring a professional mold removal service.
Consult a Doctor: If your symptoms persist despite these measures, see a doctor or allergist. They can perform tests to determine if you have a sinus mold infection and recommend appropriate treatment.

A common mistake people make is assuming that all sunscreens are created equal. They grab the cheapest option off the shelf without considering the ingredients or the potential impact on their health. Another pitfall is neglecting nasal hygiene. Many people don’t realize that rinsing their nasal passages can be an effective way to prevent mold infections.

One real-world example is Maria, a Miami Beach resident who suffered from chronic sinus infections for years. She tried everything, from antibiotics to allergy medications, but nothing seemed to work. It wasn’t until she switched to a mineral sunscreen and started rinsing her nasal passages regularly that her symptoms finally improved.

Another case involves a group of surfers in South Florida who noticed that their sinus problems worsened after spending time in the ocean. They discovered that the sunscreen they were using contained oxybenzone, which was likely contributing to mold growth in their sinuses. After switching to a mineral sunscreen and implementing a nasal hygiene routine, their symptoms significantly improved.

The link between sunscreen ingredients and sinus mold is a complex issue, but it’s one that Miami residents need to be aware of. By choosing your sunscreen wisely, practicing good nasal hygiene, and addressing indoor mold issues, you can protect yourself from this hidden health hazard and enjoy the sun without sacrificing your sinuses. Don’t let your quest for sun protection turn into a moldy mess.