Key Highlights

• High-altitude ash from Ethiopia’s Hayli Gubbi volcano has drifted toward northern India, prompting concerns about volcanic ash health risks in an already polluted region.
• WHO, USGS and IVHHN research shows that fine ash particles behave like PM2.5 and can aggravate asthma, COPD, and cardiovascular stress.
• IMD notes limited ground-level impact, but vulnerable groups may still face increased exposure risks due to Delhi’s baseline “very poor” AQI levels.

Opening Overview

The arrival of high-altitude ash from Ethiopia’s Hayli Gubbi eruption has intensified concern about volcanic ash health risks, especially in Delhi NCR where air pollution already sits at hazardous thresholds. According to observations shared with national meteorological agencies, ash clouds travelling at altitudes between 25,000 and 45,000 feet have entered Indian airspace, raising questions about how these particles might interact with the region’s persistent smog. Although IMD scientists note that a major spike in surface-level pollution is unlikely, the event brings renewed attention to how ash behaves, spreads and affects human health.

Unlike ordinary dust, volcanic ash consists of pulverised rock, minerals and tiny shards of natural glass. The World Health Organization describes these particles as “respirable hazards” because many fall below 10 microns in diameter, meaning they can bypass the body’s filtration system and lodge deep in the lungs. For a region like Delhi, where the annual PM2.5 concentration exceeds WHO’s recommended limit by more than 15 times according to the United Nations Environment Programme, even marginal increases in particulate stress can have measurable health consequences.

As scientists track the plume’s movement, residents are being urged to understand the nature of volcanic ash health risks and adopt reasonable precautions. In a city where respiratory illness is widespread and chronic exposure to pollutants is already a daily burden, knowledge and preparedness remain critical tools. The sections below offer an evidence-based assessment of potential impacts, expert opinions, and protective steps tailored for Indian urban conditions.

How Volcanic Ash Affects the Lungs and Airways

Key Points:
• Fine particles behave like PM2.5, increasing volcanic ash health risks in polluted environments.
• WHO and USGS research identifies strong links between ash inhalation and respiratory irritation, asthma flare-ups, and reduced lung function.

Research from the United States Geological Survey (USGS) shows that volcanic ash particles often range from 2 to 10 microns. These particles behave similarly to PM2.5 pollution, meaning they can penetrate deep into the bronchioles and alveoli. This characteristic significantly elevates volcanic ash health risks, especially for people in regions already exposed to persistent smog.

WHO’s environmental health guidelines state that any rise in fine particulate concentration, even short-term, is associated with increased hospital visits for respiratory distress. In Delhi, around 17 percent of adults report asthma or asthma-like symptoms according to data cited by India’s Ministry of Health and Family Welfare, reinforcing the need for added vigilance during an ash event.

The International Volcanic Health Hazard Network (IVHHN) further warns that ash particles may contain acidic coatings formed by sulphur dioxide and water vapour. When inhaled, these coatings can inflame the upper airways and trigger bronchospasm, a condition in which airway muscles tighten rapidly. The network highlights that although long-term exposure is rare in distant plume events, vulnerable individuals may still develop short-term issues, including wheezing, chest discomfort and breathlessness.

In the context of Delhi, where PM2.5 levels frequently exceed 250 µg/m³ during winter, the combination of smog and trace ash particles can heighten sensitivity among children, older adults and those with chronic diseases. This convergence underscores why respiratory experts encourage indoor protection, air-tightening of homes and proper filtration whenever there is a credible plume movement advisory.

URGENT !
High alert as ash cloud from an Ethiopian volcanic eruption to reach north west India tonight and further towards Delhi. Many flights canceled.

DGCA has issued 'urgent operational advisory'

1/2 pic.twitter.com/ASnB1kFCNC

— Defence News Of INDIA (@DefenceNewsOfIN) November 24, 2025

Chemical and Gaseous Components of Ash and Their Health Impact

Key Points:
• volcanic ash health risks release sulphur dioxide, which forms acidic aerosols known as vog.
• SO2 exposure compounds volcanic ash health risks, especially for individuals with asthma or heart disease.

Beyond particulate matter, volcanic emissions contain gases that can enhance volcanic ash health risks even when ashfall is minimal. Data from the World Meteorological Organization (WMO) shows that active volcanoes can release thousands of tonnes of sulphur dioxide (SO2) into the atmosphere per day. When SO2 interacts with atmospheric moisture, it forms sulphate aerosols, creating a haze known as volcanic smog or “vog.”

The United States Environmental Protection Agency (EPA) identifies SO2 as a trigger for airway inflammation at concentrations as low as 0.2 ppm for sensitive individuals. Symptoms include coughing, chest tightness and reduced lung function. For Delhi residents already experiencing pollution-related stress, exposure to trace amounts of vog can amplify irritation.

Medical literature from respiratory associations also identifies an increased burden on the cardiovascular system during SO2 exposure, especially among those with pre-existing conditions. Elevated SO2 can temporarily reduce oxygen exchange efficiency, increasing strain on the heart and lungs.

In high-altitude plume events like the current Ethiopian eruption, much of the SO2 remains in the upper atmosphere. However, atmospheric researchers at IMD note that minor downward mixing is possible when weather systems fluctuate. Because Delhi’s AQI already reaches “very poor” levels during this period, any slight addition to the chemical load can worsen discomfort for sensitive groups.

Residents are advised to monitor official advisories and consider using indoor air purifiers with HEPA and activated carbon filters, which help reduce the combined particulate-gas burden. While the ash is unlikely to accumulate visibly on the ground, the chemical interactions highlight why volcanic ash health risks must be assessed beyond physical particles alone.

🌋 BIG BREAKING — Volcanic Ash From Ethiopia Now Entering India’s Airspace

India’s DGCA has issued an urgent operational advisory after a massive high-altitude ash plume from Ethiopia’s Hayli Gubbi volcano — erupting after nearly 12,000 years — began drifting eastward following… pic.twitter.com/Ck3MIXPQQW

— Prashant (@prashant10gaur) November 25, 2025

Visible and Non-Visible Health Effects: Eyes, Skin and Psychological Stress

Key Points:
• Eye and skin irritation contribute to broader volcanic ash health risks during plume events.
• Stress responses and uncertainty can affect mental well-being in already polluted urban spaces.

Although respiratory effects dominate public discussion about volcanic ash health risks, scientific assessments show that ash can irritate multiple parts of the body. Fine particles suspended in the air can scratch the corneal surface, leading to redness, tearing, and a gritty sensation. The World Health Organization’s environmental exposure guidelines highlight that even low concentrations may trigger irritation in windy or dry conditions.

Skin contact with ash typically results in dryness or itching, particularly when particles combine with sweat or pre-existing dermatitis. While these reactions are generally mild, they can be more noticeable for outdoor workers and individuals with sensitive skin.

A lesser-discussed dimension of volcanic ash health risks relates to psychological stress. Uncertainty regarding air quality, visibility changes and health advisories can provoke anxiety, especially in regions like Delhi where pollution already affects daily routines. The United Nations Office for Disaster Risk Reduction (UNDRR) reports that populations exposed to environmental hazards often experience heightened stress, sleep disturbance and anticipatory worry.

In Delhi’s context, where prolonged smog episodes already contribute to mental fatigue, the arrival of a volcanic plume—even without severe ground impact—can trigger concern. For this reason, experts recommend staying informed through government updates rather than relying on unverified media claims. Maintaining routine indoor activities, hydration and moderate physical movement also helps reduce the physiological stress response.

Together, these factors illustrate how volcanic ash health risks extend beyond the lungs, affecting general comfort and mental well-being even when ash levels remain largely invisible.

What Delhi Residents Should Do: Evidence-Based Protective Measures

Key Points:
• WHO, CDC and IVHHN guidelines offer practical defences against volcanic ash health risks.
• N95 masks, indoor filtration and exposure reduction are key strategies.

Public-health organisations provide clear guidance on reducing exposure to volcanic ash health risks, especially in dense urban environments. The World Health Organization emphasises limiting outdoor activities during plume events, as fine ash particles can linger in the air long after their initial arrival. For Delhi residents already facing high PM2.5 levels, this guidance becomes even more relevant.

The Centers for Disease Control and Prevention (CDC) states that N95 or P100 respirators offer the most effective protection because their filtration capacity is designed to capture particles below 10 microns. In contrast, cloth and surgical masks provide negligible defence. Residents who must travel outdoors are advised to use well-sealed respirators and avoid strenuous physical activity.

Indoor safety measures also feature prominently in international guidelines. The IVHHN recommends sealing windows, switching air conditioners to recirculation mode and using HEPA-based air purifiers. These devices can significantly reduce indoor particulate concentration, helping mitigate volcanic ash health risks for vulnerable groups such as older adults, infants and individuals with heart or lung disease.

Outdoor surfaces should be cleaned using damp methods rather than dry sweeping to prevent ash from becoming airborne again. Although Delhi may not experience visible ashfall due to the plume’s altitude, this advice holds if particles settle lightly on balconies or terraces.

WHO’s environmental health division also advises individuals with asthma, COPD or chronic bronchitis to keep all prescribed medication accessible. Sudden respiratory irritation can occur even with low particulate concentrations, and timely use of inhalers or bronchodilators can prevent complications.

Finally, residents should follow IMD and Ministry of Health communications for real-time updates. Accurate information helps the public respond appropriately without panic, reducing both physical and psychological components of volcanic ash health risks.

Closing Assessment

The movement of high-altitude ash from Ethiopia’s eruption toward India serves as a reminder that environmental events can have international reach. For Delhi, the primary concern is not large-scale ashfall but the cumulative effect of fine particles and gases on an already strained population. Scientific assessments from WHO, USGS and IVHHN demonstrate that fine ash behaves like PM2.5, reinforcing why volcanic ash health risks must be taken seriously even when the visible impact appears minimal.

Meteorological projections indicate limited surface-level deterioration, yet the combination of pre-existing pollution, seasonal smog and heightened chemical load can challenge the city’s most vulnerable residents. Taking precautionary steps, such as proper masking, indoor air filtration and careful monitoring of symptoms, helps minimise unnecessary harm.

In a region where respiratory conditions are prevalent and baseline air quality remains poor, preparedness is not merely optional—it is essential. Understanding the science behind volcanic ash health risks, staying informed and taking evidence-based protective actions can significantly reduce health impacts. This event demonstrates that proactive behaviour, grounded in verified environmental guidance, enables communities to navigate complex atmospheric events with resilience and clarity