FAQs on Volcanic Ash

PROPERTIES OF VOLCANIC ASH

1)        What are the physical / chemical properties of volcanic ash? Are mercury, fluoride or any other heavy metals released into the environment during a volcanic eruption? If so, do these heavy metals pose any health concerns?

Volcanic ash particles are pieces of pulverised rock like sand or rock dust made of silica with some amounts of potassium, aluminium and iron. Trace quantities of other metals may also be present but these are not high enough to pose any health problems.

There is some indication that volcanic ash is less harmful compared with haze particles or other particles present in air pollution, although there are few studies in this area. Nonetheless, to be on the safe side, the health effects of volcanic ash can be considered to be similar to particulate air pollutants. NEA will monitor the situation and provide health advisories if there is a need.

HEALTH CONCERNS OF VOLCANIC ASH

2)        What are the possible health effects resulting from exposure to volcanic ash?

Volcanic ash particles that are 10 micrometres or smaller (in the PM₁₀ range) can pass through the nose and throat, and get into the lungs. Particles larger than 10 micrometres do not usually reach the lungs, but they can irritate the eyes, nose and throat.

Among healthy individuals, short term exposure (i.e. continuous exposure to unhealthy daily average PSI levels over a period of a few days) to high levels of volcanic ash may irritate the nose, throat, airways, skin, and eyes. Such irritation resolves on its own in most cases. One to three days lag between exposure and the development of symptoms may be experienced^[1].

Volcanic ash particles can affect the heart and lungs, especially in people who already have chronic heart or lung disease e.g. asthma, chronic obstructive pulmonary disease (COPD), or heart failure.

The severity of these problems depends on the concentration of ash and the duration of exposure to ash. However, the amount of ash that may reach Singapore is likely to be small and the duration relatively short.

3)        Will there be an index, similar to PSI in a haze situation, to inform us about the concentration of volcanic ash in the air?

The PSI adopted by Singapore would also apply for a volcanic ash incident. If Singapore is affected by volcanic ash, NEA will issue health advisories based on the PSI levels.

4)        Which group of people are more susceptible to volcanic ash?

In general, children, elderly, and people with chronic lung disease, heart disease are more sensitive to the health effects of volcanic ash, and should adopt the preventive measures in the MOH health advisory when air quality is poor. Individuals are advised to consult their doctor should they develop breathing difficulties. In addition, it is advised that pregnant women reduce exposure to volcanic ash for the health of their unborn baby. Contact lens users may wish to avoid the use of contact lenses as fine ash may get under the lens.

5)        Is it safe to carry on with my daily outdoor activities as usual if we are affected by volcanic ash? What are some of the measures I can take to protect myself from the volcanic ash?

The public is recommended to adhere to the MOH health advisory for the general public (Annex A).

In most cases, it is still safe to carry on with outdoor activities. However, do drink plenty of water to stay well hydrated.  Individuals with existing chronic heart and lung conditions should ensure that your medications are on hand and readily available.

Nonetheless, please note that each individual’s reaction to volcanic ash may vary, and the amount of physical activity or exertion that can be performed differs according to an individual’s health status or physical capacity. Should you encounter symptoms or discomfort, please take additional measures to prevent further exposure.

Although the general advice to the public when the air quality is good or moderate (PSI≤100) is to maintain normal activities, vulnerable persons, especially those with chronic heart and lung conditions, who develop symptoms or feel unwell should seek medical attention promptly.

6)        What should I do if I have skin irritation or breathing difficulties?

You should wash ash off your skin and out of your eyes with water. See a doctor if the irritation persists. You should also see a doctor immediately if you develop breathing difficulties.

7)           How will the volcanic ash impact patients in nursing homes and subsidised wards with natural ventilation?

These patients are indoors and sedentary. The healthcare institutions, such as hospitals and nursing homes, will monitor patients closely, and ensure ample air circulation indoors.

8)           Where can I get more information on volcanic ash?

Please refer to the following websites:  http://www.nea.gov.sg/psi/   

[1] These include nasal irritation and discharge; throat irritation and sore throat, sometimes accompanied by a dry cough; sticky discharge or excessive tearing; and acute conjunctivitis leading to redness and photosensitivity.

For FAQs on use of masks and availability of masks, please refer hereopens in a new window.

ANNEX A

MOH HEALTH ADVISORY FOR THE GENERAL PUBLIC (17 March 2014)

The health impact of haze is dependent on one’s health status (e.g. whether one has pre-existing chronic heart or lung disease), the PSI level, and the duration and intensity of outdoor activity. Reducing outdoor activities and physical exertion can help limit the ill effects from haze exposure. Persons who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention.

* Although the general advice to the public when the air quality is good or moderate (PSI≤100) is to maintain normal activities, vulnerable persons, especially those with chronic heart and lung conditions, who develop symptoms or feel unwell should seek medical attention promptly.

Prolonged = continuous exposure for several hours
Strenuous = involving a lot of energy or effort
Reduce = do less
Minimise = do as little as possible
Avoid = do not do