Mysterious Fog in the US , Canada and UK: A dense, eerie fog with a "burning chemical-like smell" has spooked a good part of North America and parts of the United Kingdom and Canada. With social media amplifying all concerns, this phenomenon has sparked attention across all social media platforms. However, at the heart of this mysterious fog are a conjunction of natural events, social psychology, and environmental conditions that culminated in all the conspiracy theories and public health fears. Here's a closer look at the mysterious fog, its potential causes, and the societal response it has triggered.

Fog that Feeds Fear

The first reports of this "mysterious fog" came in from Florida where a resident said that they experienced respiratory symptoms, feverish warmth, and stomach cramps after contact with the fog. Similar stories started flooding social media, and within a day or two, a sinister force seemed to sweep across the United States, Canada, and parts of the UK. From Texas to Minnesota, people reported weird odors and health issues that they thought were linked to this bizarre atmospheric event.

Some witnesses were said to see "white particles" swirling through the air; theories ranged from a chemical attack or experimental weapon to drone-related chemical dispersals and references to historical military experiments, such as the infamous 1950s "Operation Sea-Spray."

Fuel to the fire were added when videos and posts, hundreds of thousands in number, began circulating on social media sites like TikTok and X (formerly Twitter) speculating on the origin of the fog. Hashtags like #ToxicFog went trending for days. Hysteria created a self-reinforcing loop in which every post spurred further scrutiny and fear.

Scientific Explanation of the Dense Mysterious Fog

1. What is Fog?

Fog is essentially a low-lying cloud formed when the air temperature cools to its dew point, causing water vapor to condense into tiny droplets or ice crystals. Several types of fog—advection fog, radiation fog, and valley fog—can form depending on conditions such as warm, moist air moving over cooler land or when temperatures plummet rapidly under clear skies.

2. Why the Chemical Smell?

Such chemical-like smell as reported during the occurrence of fog events is sometimes attributed to air pollution. It acts like a sponge, where it absorbs these pollutants, which include sulfur dioxide and nitrogen oxides, among others, that emit from industries. This mixture, therefore, leads to a stench that could be mistaken as unnatural or even toxic.

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

3. What are the Health Concerns?

High moisture levels from fog can significantly exacerbate symptoms related to respiration, but especially in already predisposed asthmatics and allergy patients. The connection of these symptoms with actual fever, stomach cramps, and puffy eyes is too remote. Experts assume that the irritating effects of entrapped pollutants trapped in fog tend to affect more the eyes and throat rather than the rest of the body affected by some report.

Psychological Effects of Mass Panic Caused by Social Media

Social media amplified a natural weather event into a health epidemic. It made the personal experience of individuals become a cause for fear and speculation, a domino effect.

According to psychologists, this is a concept of selective perception, wherein once people's attention is drawn to environmental anomalies, they begin to notice them. This mirrors earlier panics, such as the Seattle windshield pitting panic of 1954. Then, atomic bomb testing caused fear in many and started to have people looking at their windshields for small marks that they had not seen before. Likewise, postings on the strangeness of the fog probably increased public awareness and suspicion, with people looking to attach unrelated symptoms to the phenomenon.

The fog hysteria shares a commonality with other instances of mass panic, such as the "drone sightings" of recent years or the Cold War-era fears of biological warfare.

Also Read: Mysterious Fog Is Making Americans Sick

These events underscore how fear can cloud judgment, especially when amplified by social media and sensationalist headlines. While historical cases, such as "Operation Sea-Spray," offer concrete evidence of the existence of unethical experiments, the jump from a natural weather condition to theories of chemical attacks exemplifies a more modern trend of connecting unrelated dots, all wonderfully seeded in distrust and anxiety.

Despite the swirling rumors, meteorologists and scientists are in agreement that the mysterious fog is not as alarming as it seems. It is well known that fog traps and amplifies pollutants, especially in urban and industrial regions. Moreover, winter months are the most conducive for fog formation, so its recent prevalence is unsurprising.

On the other hand, environmentalists advise that the fog should wake everyone up to increased levels of pollution. The reported odors and health irritations could be just symptoms of far deeper systemic issues like industrial emissions and lack of control over air quality.

The authorities must be transparent in their communication to combat misinformation and allay public fears. Governments and environmental agencies must provide timely updates on weather phenomena, air quality, and health risks. Initiatives like real-time pollutant tracking and public education campaigns can help demystify natural occurrences while addressing valid environmental concerns.

The mysterious Canada fog is a compelling case study in how environmental events intersect with psychology and societal dynamics. While rooted in natural phenomena, the fog became a vessel for collective fears, amplified by modern technology and historical anxieties.

In this information era where communication occurs at an almost lightning pace, the fog becomes a metaphor that reminds everyone about scientific literacy, environmental responsibility, and an effective balance when considering public concern. Whether perceived as a marvel of nature or as a tale that serves to teach, it left a very powerful mark in people's minds.

After some days of relief, on Sunday, Delhi again woke up to a thick layer of smog, with pollution levels rising up to 'very poor' category. The centre's early warning system (EWS) forecast that air quality index (AQI) will further deteriorate.

On Sunday, by 7pm, Delhi's AQI was at 299, just below 'very poor' level on the index. Anand Vihar remained at severe levels with the AQI logged at 421 at 11am, by evening, it rose to 428. Wazirpur also slipped into the 'severe' category with an AQI of 408.

As Delhi continues to struggle with smog-filled skies, and thick layer of smoke to breathe through, an earlier video by Dr Divya Prakash, Consultant Physician at Yashoda Hospital on tips to stay safe amid Delhi pollution is making rounds.

What Does The Doctor Say?

Dr Prakash points out that the moment the index goes above 50, the air starts to become unhealthy for us, however, in Delhi, we already see the AQI levels crossing the 400 threshold.

"The main problem is with our lungs due to increasing air pollution. It also indirectly affects our heart and brain. So, how can we save ourselves from this?" He shares that the best way is to use public transports and electric vehicles. He also recommends wearing a mask whenever anyone goes out and urges people to avoid going out at peak hours.

"Eat healthy food, avoid burning wood or construction work around the house and do use your air purifier at home, especially for children and elderly and those who already have lung or other heart problems," he says.

How Poor AQI Impacts Our Lungs?

Air pollution comprises of tiny pollutants and particles called the PM2.5 and PM10, that reach deep into our lungs. These particles, though tiny, are able to inflame the airways and cause breathlessness, wheezing, and repeated coughing. This can further cause healthy adults to suffer from throat irritation, headaches, and fatigue if they are exposed for a long time.

Since children inhale more air per kilogram of body weight than adults, they are at more risk of being harmed by the pollutants. Furthermore, they also have a weaker immunity, which puts them at more risk of such complications.

The World Health Organization (WHO) also notes that not just lungs, but almost every organ in the body can be impacted by air pollution. Thanks to the small size of the pollutants, they can penetrate into the bloodstream via lungs and then circulate throughout the body and could lead to systemic inflammation and carcinogenicity.

What Diseases Could Air Pollution Cause?

Apart from the respiratory diseases like asthma, shortness of breath, COPD, WHO notes that air pollution could is a risk for all-cause mortality as well as diseases like:

• Stroke
• Ischaemic heart disease
• Lung cancer
• Pneumonia
• Cataract

There are evidence that support the link between air pollution exposure and adverse pregnancy outcomes, including low birth weight of the child, small for gestational age, and other cancers, diabetes, and cognitive impairment and neurological disorders in the child.

How Can You Read AQI?

As per the Central Pollution Control Board, here's how the data on AQI can be interpreted

• 0-50 is considered ‘good’
• 51-100 is considered ‘satisfactory’
• 101-200 is considered ‘moderate’
• 201-300 is considered ‘poor’
• 301-400 is considered ‘very poor’
• 401-500 is considered ‘severe’

Delhi witnessed a slight improvement in its Air Quality Index (AQI) for a couple of days before it again slipped back to 'very poor' category. On Sunday morning, some areas in fact reached 'severe' category on the AQI.

While pollution spiked during Diwali, on Friday and Saturday, Delhi's AQI was recorded at 275 and 292 respectively, which has placed the air quality category in 'poor'.

However, on Sunday morning, Delhiites woke up to 'very poor' air quality, thanks to the thick layer of smog. The AQI was recorded well above 300 in most areas. Visuals too show low visibility in many areas of the national capital.

What Does The Expert Say About The Air Quality?

On Sunday, as of 7am, Delhi's Anand Vihar area recorded an AQI of 430, which has placed it under the 'severe' category. Wazirpur also recorded an AQI of 403, further placing it under the 'severe' category. Speaking to ANI, former AIIMS Director Dr Randeep Guleria urged people to use preventative measures in order to minimize their exposure to the polluted air. He also warned people of the health implications which could be the result of deteriorating air quality.

"The current high levels of air pollution, indicated by poor AQI, are leading to acute health effects, particularly among individuals with underlying heart or lung conditions, the elderly, and young children. These groups are experiencing increased chest discomfort, breathing difficulty, cough, and worsening of pre-existing conditions like asthma and COPD," Dr Guleria told ANI, on Friday.

"Even healthy individuals are reporting symptoms such as nasal stuffiness, throat pain, chest tightness, and coughing. The inflammation and narrowing of airways caused by pollutants are contributing to these issues. Additionally, the use of crackers, despite permissions for 'green crackers,' has exacerbated air pollution," he added.

What Preventative Measures Should One Use?

The best way to protect yourself is by limiting your outdoor timings, especially during the early morning hours and at the night. Smog is at its lowest during the afternoon. Furthermore, using an N-95 respirator could protect you from the minute pollutant particles in the air.

N-95 is a respiratory protective device designed to achieve a very close facial fit and very efficient filtration of airborne particles, notes the FDA. This is what makes it fit for use during high levels of pollution.

The edges of N-95 are designed to form a seal around the nose and mouth. Some models even have exhalation valves that can make breathing out easier and help reduce the heat build-up.

As per a 2021 study published in the Indian Journal of Radiology and Imaging, the N-95 mask could block "at least 95% of very small test particles".

Read More: Which Mask To Wear For Best Protection?

What Does AQI Mean?

As per the Central Pollution Control Board, here's how the data on AQI can be interpreted

• 0-50 is considered ‘good’
• 51-100 is considered ‘satisfactory’
• 101-200 is considered ‘moderate’
• 201-300 is considered ‘poor’
• 301-400 is considered ‘very poor’
• 401-500 is considered ‘severe’

Delhi AQI as of 7am

Alipur, Delhi (DPCC) - 309.00

Anand Vihar, Delhi (DPCC) - 430.00

Ashok Vihar, Delhi (DPCC) - 369.00

Aya Nagar, Delhi (IMD) - 272.00

Bawana, Delhi (DPCC) - 390.00

Burari Crossing, Delhi (IMD) - 344.00

CRRI Mathura Road, Delhi (IMD) - 330.00

Chandni Chowk, Delhi (IITM) - 376.00

DTU, Delhi (CPCB) - 266.00

Dr. Karni Singh Shooting Range, Delhi (DPCC) - 317.00

Dwarka-Sector 8, Delhi (DPCC) - 301.00

IGI Airport (T3), Delhi (IMD) - 269.00

IHBAS, Dilshad Garden, Delhi (CPCB) - 310.00

ITO, Delhi (CPCB) - 329.00

Jahangirpuri, Delhi (DPCC) - 370.00

Jawaharlal Nehru Stadium, Delhi (DPCC) - 304.00

Over 141,000 bottles of popular cholesterol medication, Atorvastatin Calcium Tablets, have been recalled as it "failed dissolution specifications". This means the drugs did not pass a solubility test or failed to dissolve at the standard rate.

As per the report by the US Food and Drug Administration (FDA), Ascend Laboratories, LLC, which is a New Jersey-based pharmaceutical company was the first to recall the use of the tablets on September 19, 2025.

Following that, this month the drugs have been recalled under Class II recall, which means that the product may cause temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote, notes the FDA.

Which Medicines Have Been Recalled?

The current recall only affects the bottles of 10mg, 20mg, 40mg, and 80mg of the said drugs, manufactured by Alkem Laboratories, Ltd. of India. The drugs were distributed by Ascend. The recalled bottles contained tablets which ranged from 90-count to 1000-count bottles.

The FDA is urging people to speak to a doctor or pharmacist before stopping their cholesterol medicine, or switching to any alternatives. The FDA explains, "consumers can generally continue taking the medicine unless the recalling company provides other instructions. In some instances, stopping your medicine may be more harmful to your health than continuing to take the recalled medicine."

What Is A Dissolution Test?

This test is conducted to determine the compliance of the drug with the dissolution requirements for dosage forms to be administrated orally.

Dissolution specifications are quality control limits for drug products that define the acceptable amount of drug substance that must dissolve in a specified time under laboratory conditions. The test also ensures batch-to-batch consistency and predicts how a drug will be released in the body, providing a surrogate measure of clinical performance.

The specifications are based on data from batches, which are used in clinical trials and are then guided by the drug's properties and the dosage form. They vary depending on the drug release types, which could be categorized under three kinds:

• Immediate Release (IR)
• Extended Release (ER)
• Delayed Release (DR)

What Does FDA Say About This Recall?

As per the FDA, Class I recalls are the most serious, this is where there is a reasonable probability that using or being exposed to the recalled drug could cause serious health consequences to the customer. This recall involves removing the drug from the market and are conducted at consumer level.

Class II recall however could cause temporary health consequences but the probability of health issue is remove. FDA notes that "these recalls are generally conducted at the retail level, and patients and consumers can continue using the medicine unless otherwise directed by the recalling company or FDA."

FDA says that for class II or class III recalls, consumers may "generally continue taking the medicine unless the recalling company provides other instructions".