A heavy fog that "smells like chemicals" has been covering several parts of the United States lately, raising health concerns for people exposed to it. Reports have described sore throats and coughing, fatigue, and eye irritation among the exposed. But why does this fog smell so weird, and why are some people falling ill?

In this article, we will explore the science behind this phenomenon, how fog forms, and why it might sometimes carry chemical odors that linger in the air. By the end, we will also debunk some of the more speculative claims that have surfaced in the wake of this mysterious fog event.

The ‘Chemical Fog’ and Its Health Impacts

The fog has started trending on social media, with multiple users saying that it smells of fireworks, chemicals, or even sewage. David Bamber of St. Petersburg, Florida, shared a very popular TikTok video describing the sensation of walking through the fog and having the feeling of inhaling something toxic. Others reported developing respiratory conditions, including sore throats, coughs, and general fatigue, which they blamed directly on the fog. In fact, a Florida resident described how, following a short detour at a gas station, she started sneezing uncontrollably and became feverish, with stomach cramps as well. For some, this "sickness-fog" has become an urgent health issue.

As alarming as this is, the mist might not seem so evil. After all, there are scientifically established reasons about how fog functions with its surroundings, especially relating to pollutants, which could strengthen the odor it has.

Fog Formation and Its Chemical Absorption

This takes place when the water vapor present in the air condenses to become small water droplets and eventually form a low-lying cloud, making visibility hard to perceive. Such droplets will act as natural scavengers absorbing all airborne pollutants and particles. Moisture contained within the fog will amplify the concentration of pollutants such as chemicals and odors to make them much stronger and hence easily noticed.

According to Washington University atmospheric scientist Professor Rudolf Husar, chemicals trapped within the fog droplets "include sulfur oxides and nitrogen oxides, gases primarily produced by industrial activity, vehicle emissions, and, more rarely, natural fires. Those chemicals stay in the air a long time, especially because when they are trapped in these droplets, they become concentrated and kindle chemicals and odors in the surrounding environment.". This process is known as "scavenging," where fog droplets absorb gases and pollutants, allowing them to linger longer than they might in clearer air.

Also Read: Health Concerns Rise As US, Canada, and UK Come Under The Blanket Of Thick, Dense, Toxic Fog

The reason why this fog smells so potently is that humidity increases the way smells move. When water molecules in the air combine with odor-causing molecules, they tend to last longer and thus become more pronounced to our noses. This explains why some people have reported that the fog smells like chemicals or even like sewage, depending on the surrounding environment's air quality.

What Role Does Atmospheric Conditions and Pollutants Play?

More than just an atmospheric visual appearance, fog could often trap most kinds of pollutants when the ground-adjacent layers are extremely cold, often experienced during the cold season. As it douses many inhabited spaces, pollution is able to cling with the fog through smokes emitted from vehicles, factory chemicals, among other things. When people inhale this "chemical fog," they may feel irritation in the respiratory system. It is particularly more sensitive to individuals with pre-existing conditions, like asthma, who have airways that are easily irritated by a change in air quality.

In addition, air pollution generally causes a variety of health issues, from simple coughing and congestion to severe respiratory problems. The moisture of the fog increases these effects, introducing more water into the lungs and causing irritation. This is why some people may feel shortness of breath, chest pain, or even experience wheezing when exposed to dense, polluted fog.

Fogs often occur where, for instance, Florida regions do, following a specific set of weather, often temperature inversion. In cases of temperature inversions, there will be cooler air trapped very close to Earth by warmer air over it so that pollutants from whatever source have less space to dispel into the atmosphere. That accumulated pollutant within the fog contributes to having that chemical even more pungent.

Besides pollution, local moisture sources heavily influence fog. For example, areas next to large bodies of water like the San Francisco Bay often see thick fog in summer months as the water chills the surrounding air. However, in some areas, fog can form where moisture from the ground is evaporating into the air, condensing, and forming thick fog near the surface. Moisture, once condensed, can absorb pollutants and enhance existing odors.

Is There a Conspiracy Behind the Fog?

As the fog event has continued, some people have begun to speculate that there might be a more sinister or secretive explanation for the phenomenon. Conspiracy theories have been circulated, suggesting that the fog could be the result of a chemical weapon or even a government experiment. Such claims have largely been fueled by comparisons to Operation Sea Spray, a controversial U.S. The Navy biological warfare experiment in the 1950s where bacteria were released in the San Francisco Bay area to test the city's vulnerability to biowarfare.

Also Read: When Fear Clouds Judgment- The Psychology Behind The Mysterious Fog Over US And Canada

Even if the thought of a planned chemical fog, produced by humans, is quite threatening, science cannot prove such an idea. In fact, according to experts, the cause for the fog may simply be a part of the regular weather, in combination with higher concentrations of pollutants from human sources. Chemicals in the air, specifically sulfur and nitrogen compounds, are nothing but by-products of industrial pollution, not some sort of deliberate attack.

Why Does Fog Smell Like Chemicals?

In summary, the chemical-like odor produced by fog is a result of various environmental and atmospheric conditions. Due to fog's natural collecting characteristic, pollutants are trapped inside the fog droplets, which are very small in size. Thus, these pollutants include sulfur and nitrogen oxides, which are usually derived from vehicle emissions, industrial processes, and even wildfire cases. The moisture in the fog makes these odors more observable and potent.

Fog is not dangerous in itself, but the pollutants it captures can cause irritation to the respiratory system, especially for people who have pre-existing health conditions. Knowing how fog forms and how it interacts with its surroundings will help us prepare better for the effects of fog and address health concerns that may be triggered.

Even if this recent bout of fog caused concern, there's scientific logic for why this situation is not to be worried about. Nonetheless, being cognizant and knowing the quality of air is also a form of mitigation from this thick chemical smell fog that affects health.

You may have heard people say that they are allergic to things, whether it is gluten, soy or peanuts. These people avoid these items, even going as far as not dining in certain places where there is a possibility of cross contamination.

While it may seem like an overreaction, allergy symptoms can range from just a few rashes to cause of death. There are many people who did not and still do not take allergies seriously. As one of the most common allergies, many people who have close ones with peanut allergy, many places have opened “nut-free” zones including schools, offices and many public spaces.

While there is no cure for allergies, a new clinical trial results show that exposure therapy with peanut allergies has proven successful.

Why Do We Need Exposure Therapy?

The research team reported in the journal Allergy, April 2025, that a significant majority of the participants, more than two out of every three (67%), were able to eat at least five peanuts without triggering an allergic reaction after undergoing the treatment. This marks a positive step forward in managing this common and often severe allergy.

Seeing as expansive as the risk associated with allergies is, researchers have continued working towards proper cures and treatments. While there are precautions like avoiding the allergens, reducing exposure, when a person with a sever, allergy is exposed to the allergens, the chances of them going into anaphylaxis is a lot, so many people care EpiPens or epinephrine shot that can counter allergic reactions for a while.

How Does Exposure Therapy Work For Peanut Allergies?

The way exposure therapy works is pretty simple but needs to be done carefully. People who are allergic to peanuts are given very, very small amounts of peanut protein every day. Over time, the amount is slowly increased. It's like gently introducing the body to the thing it's allergic to, little by little. This helps the body learn that peanuts aren't actually a threat, and it starts to react less strongly. It's a gradual process, but the goal is to build up a person's ability to handle peanuts without having a dangerous allergic reaction.

In this study, 21 adults who were allergic to peanuts took part. Every day, they ate a small amount of peanut flour mixed in with their food. The goal was for them to be able to eat a small amount of peanut flour every day for at least a month without any problems. After that, they were tested to see how much peanut they could eat. The researchers were very happy with how well the treatment worked, saying that the results were similar to what they've seen in studies with kids.

The study showed some really impressive results in how much more peanut the participants could handle after the treatment. The researchers mentioned that on average, the amount of peanut they could eat without a reaction went up by a hundred times!

Why Are Researches Like This Important?

What makes this study really important is that it's the first-time scientists have specifically looked at how well exposure therapy works for adults with peanut allergies. Usually, this kind of treatment is done with kids because their bodies are still growing and changing. However, this new research shows that even adults, whose bodies are already fully grown, can still become less allergic to peanuts with this type of treatment. This opens up a whole new possibility for adults who have lived with this allergy for many years and haven't had many treatment options before. Many said that the treatment was "life-changing" and they no longer lived in constant fear of their allergy.

Every three seconds someone in the world develop dementia. Forgetting things every now and then is normal, it happens to everyone. However, nobody expects to lose their sense of being, all the memories and life experiences that make you who you are. Dementia is the condition that makes all of these fears come true. It is a collective name for different brain syndromes which affect one's memory, thinking, behavior as well as emotions.

Many symptoms of dementia are vague, especially early ones, and they can easily mislead people. However, a new technological advancement may help people get diagnosed early, through shoes.

How Can Shoes Help Us Diagnose Dementia?

This new technology, published in Science Advances in April 2025, works by using special insoles you put inside your shoes. These insoles have tiny sensors that can feel the pressure when you walk or stand. What's really clever is that these sensors don't just feel pressure; they turn that pressure into tiny electrical signals. These signals carry hidden information about how you move and how your body is working, kind of like secret messages from your feet that can tell a story about your health without you even realizing.

How Do These Shoes Work?

The electrical signals created by the smart insoles are then sent wirelessly to a special application on your smartphone, just like getting a text message. This app takes all that data and turns it into easy-to-understand pictures and information about how you walk and stand. It can show exactly where you put the most pressure on your feet and how your movement changes over time. Even more impressively, the app uses smart computer programs to learn and recognize different ways you move, like sitting, standing, or running, giving a detailed look at your daily activities.

For patients who might be developing health issues, the smart insoles could provide early clues that doctors can use to make diagnoses sooner. For athletes, this technology can help them understand their posture better, which can prevent injuries and improve their performance. If someone is recovering from an injury, the insoles can track their progress and make sure they are healing correctly.

Researchers have already discovered that the way people walk can change when they have certain health problems, especially conditions that affect the brain and nerves, like Parkinson's disease. People with Parkinson's might start to shuffle their feet or lean to one side when they walk. The team behind these smart insoles believes that by having much better sensors in shoes, doctors could get a more accurate and earlier warning sign of these kinds of conditions just by analyzing someone's walk. This could lead to earlier treatments and better management of these challenging illnesses.

Why Is Early Diagnosis Important?

According to Alzheimer’s Disease International there are 55 million people living with dementia in 2020.

Their research shows that most of the people who have dementia have not received proper treatment for the same. About three quatre of the people who have been diagnosed with dementia lack treatment or have access to healthcare. Even in high-income countries only about 20-50% of people receive the proper care they need.

This treatment gap can only be fixed when people start getting a diagnosis. Not just receiving care, but receiving early diagnosis and treatment is crucial for proper dementia care, as explained by World Alzheimer Report 2011.

Whooping cough or pertussis, has been making headlines for its comeback across the United States. As per the recent data, there have been 8,485 reported cases for far this year. This is double the number recorded at the same time last year. The resurgence had already led to the deaths of two infants in Louisiana and a 5-year old child in Washington state over the past six months.

Pertussis is a highly contagious respiratory disease caused by the Bordetella pertussis bacterium. It is most dangerous for infants and young children, particularly before they are old enough to receive their first dose of vaccine at two months of age.

Why Are Cases Increasing?

During the COVID-19 pandemic, whooping cough cases dropped due to the increase in the use of masks, social distancing, and other preventive measures. However, it has made a comeback after 2 to 5 years as these preventive measures have decreased.

There is another factor in the increase of cases, it is the decline in vaccine rotes. As per an AP report, kindergarten vaccination coverage dropped last year, and vaccines exemptions reached an all-time high in the United States.

Public health officials worry that growing vaccine hesitancy could further fuel outbreaks of vaccine-preventable diseases like whooping cough.

Pregnant women are also recommended to receive the Tdap (tetanus, diphtheria, and pertussis) vaccine to protect their newborns. Unfortunately, vaccination rates during pregnancy remain suboptimal, leaving many babies vulnerable in their first months of life.

Which States Reported The Highest Cases?

There are certain states that have reported more numbers than others. As of the recent data, Pennsylvania reported 207 cases so far, whereas Michigan has seen an even sharper rise in cases. In 2025, Michigan has reported 516 cases, mostly among children, between ages 5 to 17. Michigan, in the last year, reported 2,081 pertussis cases.

The Centers for Disease Control and Prevention (CDC) recommends that all infants, children, adolescents, and pregnant women get vaccinated against pertussis. Adults who missed vaccinations earlier in life should also receive a dose to ensure protection.

How Does It Affect Your Body?

According to the CDC, Bordetella pertussis bacteria attach to the cilia (small hair-like structures) lining parts of the upper respiratory tract. The bacteria release toxins that damage the cilia and cause swelling, leading to severe coughing fits.

Symptoms of whooping cough can vary depending on a person’s age and vaccination status. Initial symptoms often resemble a common cold: runny nose, mild cough, and low-grade fever. However, as the disease progresses, patients may experience uncontrollable, violent coughing fits that can make it hard to breathe. The characteristic "whoop" sound often occurs when the patient gasps for air after a coughing fit.

Who Is More At Risk?

Babies under 1 year old are most at risk for severe complications, including pneumonia, seizures, and even death. Individuals with underlying health conditions like asthma or those who are immunocompromised also face a higher risk of serious illness.

How It Spreads And How Can It Be Prevented?

Whooping cough spreads easily through respiratory droplets when an infected person coughs or sneezes. People can remain contagious for at least two weeks after symptoms begin. Some individuals may only have mild symptoms yet can still unknowingly transmit the bacteria to vulnerable groups like infants.

The best way to prevent whooping cough is vaccination. Practicing good hygiene, such as frequent handwashing and covering coughs and sneezes, can also help limit the spread. In some cases, preventive antibiotics (post-exposure prophylaxis) may be recommended for those who have been in close contact with an infected person.