Health Concerns Related to Volcanic Activity
Volcanoes exist throughout much of the world, and some are located near major metropolitan centers. Occasionally, meteorological patterns may carry ash or gases from active volcanoes to populated areas, causing health concerns. Frequently, though, the perceived dangers of falling ash are actually greater than the physical risks posed by volcanic eruptions.
Unlikely exposure to lava (molten rock) via pyroclastic flow - which may cause significant burns - may be the most dramatic effect of volcanic activity, but the most likely and most significant health concern from a volcanic eruption involves respiratory problems due to exposure to volcanic ash. Thermal burns to skin or mucous membranes require proximity to lava flows, typically limiting such injuries to individuals participating in geologic or volcanic surveys or ecotourism.
In many cases, ash exposure may be unavoidable due to wind patterns that can carry volcanic ash to populated areas. People with underlying pulmonary conditions such as asthma, COPD, or lung cancers may experience difficulty breathing and could suffer from lower tolerance to physical exertion than healthier individuals. Therefore, such individuals should take additional precautions to avoid excessive ash exposure. Eye and skin symptoms may occur, as well.
Symptoms of Ash Exposure
Many symptoms of ash exposure depend on the size of the particles, the concentration of ash in the air, the duration of exposure to particles, the composition of silica and gas in the ash, the meteorological conditions, and the health of affected individuals.
Common respiratory symptoms include the following:
- Nasal discharge
- Throat irritation with or without a dry cough
- Severe symptoms of bronchitis, for those with underlying pulmonary or cardiovascular disease
- Airway irritation, for those with asthma or chronic bronchitis, such as wheezing, cough, and shortness of breath
- Discomfort when breathing
Eye symptoms may include the following:
- Sensation that there is a foreign body in the eye
- Painful, itchy, or reddened eyes
- Tearing or thickened discharge
- Corneal abrasions or scratches
- Acute conjunctivitis
Although the composition of volcanic ash varies globally, much contains various particles of "free crystalline silica." Exposure to long periods of ash quantities, meaning in excess of 50 micrograms per cubic meter in the air, has been known to cause silicosis in other environments. Silicosis is a pulmonary disease that may lead to lung cancer, and may cause respiratory impairment requiring chronic medical treatment. There have been no documented cases of silicosis due to volcanic eruptions or ash exposure, however. Exposures of short duration are unlikely to cause long-term health issues.
Besides lung and eye problems, skin irritation may also occur from the acid coating of many ash particles, and contact with bare skin can lead to irritation. Volcanic ash may also increase the risk of trauma due to reduced visibility or slip-and-falls.
Fruits and vegetables should be washed thoroughly if there was a chance of exposure to ash or other volcanic gases. Water with particulate matter or an odd odor should be filtered.
Falling ash may interrupt essential services and cause power interruptions, municipal water and sanitation delays or stoppages, and long-term agricultural issues. These complications may also increase the risk of communicable disease, if people are forced to shelter in place for extended periods of time.
Prevention of Health Issues
- Avoid exposure to ash particles whenever possible.
- To avoid inhaling ash, use a disposable respirator such as an N95, or cover the mouth and nose with a dampened handkerchief or scarf.
- If clean-up is necessary, attempt to work for short periods.
- Wet the ash to reduce airborne disruption of the particles once they have settled.
- Protect eyes with goggles or glasses.
- Try to avoid wearing contact lenses, when possible.
- Keep doors and windows closed during periods of heavy ashfall.
- For people with underlying health conditions, remain indoors during the eruption, and handle ash only in well-ventilated areas.
- Cover bare skin to prevent irritation from prolonged contact with particles.
- Take special care when driving, as reduced visibility often occurs and increases the risk of traffic accidents.
Accumulation of ash, especially when wet with rain or water from clean-up, can cause roof collapses. Avoid structural entrapments that may cause orthopedic or head injury. Take all precautions necessary to facilitate extended periods of sheltering in place.