What risks does the haze of the Sahara have on our health?

We are facing a meteorological phenomenon that causes many particles of dust, ash, clay or sand to be suspended in the atmosphere. This phenomenon is known in meteorology as haze. But in addition, it should be added to the definition that haze hinders visibility, clarity and transparency in an area (due to the presence of fine particles in suspension). Sometimes this occurs due to the effects of dust, salts (sodium) or elements of the environment, and other times as a result of special events (such as forest fires or other polluting events). What is the case this time?

Well, in this case what we are seeing is mainly sand and dust in suspension, which are being dragged by the ‘Celia’ storm. And for at least a few more days, this “temporary” is expected to continue to increase. And, of course, combined with the rainfall from the storm, it is also to be expected that “it rains mud”.

The real problem?

You may think that a few days of “bad weather” are not that bad, and you may be right, after all, this is a not so infrequent phenomenon in the Canary Islands (due to its proximity to Africa). However, let us consider the following.

The suspended particles have a very small size. This means that they can penetrate our airways and, depending on their size, even other systems in our body.

What we do know is that the quality of the air we breathe decreases, and this may not be harmless.

An index is used to measure air quality.

The Pollutant Standards Index (PSI) is a type of Air Quality Index , which is a number used to indicate the level of pollutants in the air. From 0 to 50 , we are at safe levels of pollution , with no recorded effects on health. From 51 to 100 , we are at moderate levels , but still no health effects, or at least very little.

It is from here that our health begins to be at stake. From 101 to 200 we are talking about an unhealthy level, where we can all start to experience health effects ; members of more vulnerable groups (children, the elderly, and people with chronic heart or lung disease) may experience more serious health effects. It’s not a bad time to stay home and wear a mask, having nothing to do with COVID-19 , by the way.

For sudden cardiac deaths, each 30-unit increase in PSI has been correlated with an 8.15% increased risk of out-of-hospital cardiac arrest on the same day of exposure. Furthermore, this risk was found to remain elevated for 1 to 5 days after exposure. It has also been correlated, in a weaker way, with acute myocardial infarction and acute ischemic stroke. Of course, the use of restrooms also increases per unit increase in PSI.

Short-term effects of the haze?

Prolonged exposure to these tiny particles could cause respiratory problems and aggravate existing heart or lung disease.

In healthy individuals, exposure to particles can cause discomfort to the eyes, nose, and throat. In most situations, this irritation goes away on its own within a few days and the time between exposure to haze and health effects/symptoms may be up to three days.

The aggravation of lung and heart diseases

As we told you, mist particles can sometimes affect the heart and lungs , especially in people who already have chronic heart or lung disease, such as asthma, chronic obstructive pulmonary disease (COPD), or heart failure.

Long-term effects of the haze?

Given that long-term haze does not occur in Spain, any exposure is, by definition, of short duration. Long-term studies of air quality are often carried out outside the country. Since international studies are based on long-term exposure to air pollution, there is little solid data on the long-term effects of short-term, episodic exposures to haze.

It is worth mentioning that these studies have shown that continuous exposure for several years to high environmental pollution of fine particles (that is, particles of 2.5 micrometers -less than the thickness of a human hair-), may have a greater risk . of cardiovascular effects, such as heart attacks, reduced lung development, as well as the development of chronic respiratory diseases, such as asthma, in children.

There are even some series of reported cases of premature births and low birth weight, although this requires more evidence to support it and, if this relationship exists, it is possibly more related to haze from contaminating events.

That is not our case. In our case, simply the sands of the Sahara are being dragged by a storm.

More depth…

Haze particles can cause acute symptoms such as coughing, wheezing, shortness of breath, and feelings of tiredness and weakness. However, the harmful health effects of a few minutes of exposure to haze are temporary and usually do not cause long-term health problems.

The greatest danger from haze is fine particulate matter (PM) suspended in the air. Particles, especially PM2.5, can be easily inhaled into our lungs. This refers to particles that are less than 2.5 microns in diameter.

Long-term exposure can lead to the development of medical conditions such as bronchitis and an increased incidence of lung cancer. Therefore, it is best to stay indoors during haze when the PSI is at unhealthy levels. If you have to go outside for extended periods, an N95 mask can help reduce inhalation of particulates, though those at higher risk of being affected by haze should stay indoors. These are people with pre-existing heart or lung disorders, as exposure to air pollution is known to worsen these conditions. Also, children and the elderly who have smaller lung reserves should avoid prolonged exposure to haze.

What precautions should I take?

If your symptoms are mild and you’re in good health, simply avoid the heat by staying indoors with windows and doors closed and, if you have one, turn on an effective air purifier. If, on the other hand, your symptoms are more serious or you have doubts, it is best to consult a doctor.

It should be noted that it is not recommended to self-medicate or use inhalers with which you are not familiar.

On the other hand, exercising outdoors when the PSI is in the unhealthy range (ie 100 or higher) is counterproductive. The higher the PSI, the more harmful it is to inhale polluted air when exercising. Keep in mind that when you exercise, you have to breathe harder and the air exchange that takes place in the lungs is several times greater than when you are at rest. Therefore, you are inhaling several times more air pollution.

What is the ISP in my area?

https://airindex.eea.europa.eu/Map/AQI/Viewer/

Here you have a map that shows the air quality with hourly updates, by the European Air Quality Index.

This index allows users to better understand the quality of the air where they live, work or travel. By displaying up-to-date information for Europe, users can obtain information on air quality in individual countries, regions or cities.

The index is based on the concentrations of up to five main pollutants, which are: particulate matter (PM10), fine particles (PM2.5), ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2).

References:

Cheong, Ngiam, Morgan, Pek, Tan, Lai, Koh, Ong, & Ho. (2019, 6 de Septiembre). Acute Health Impacts of the Southeast Asian Transboundary Haze Problem—A Review. International Journal of Environmental Research and Public Health, 16(18), 3286. https://doi.org/10.3390/ijerph16183286

‌Chung, O.K. (2016, 30 de Agosto). The Effects of Haze on Your Health. Mount Elizabeth Hospital. https://www.mountelizabeth.com.sg/healthplus/article/the-effects-of-haze-on-your-health

‌European Air Quality Index. (2022). Europa.eu. https://airindex.eea.europa.eu/Map/AQI/Viewer/

Jaafar, H., Azzeri, A., Isahak, M., & Dahlui, M. (2021, 30 de Noviembre). The Impact of Haze on Healthcare Utilizations for Acute Respiratory Diseases: Evidence From Malaysia. Frontiers in Ecology and Evolution, 9. https://doi.org/10.3389/fevo.2021.764300

Ministry of Health Singapore (2021). FAQs on Haze Health Advisory. Moh.gov.sg. https://www.moh.gov.sg/resources-statistics/educational-resources/haze/faqs-on-haze-health-advisory

Wang, J., Wei, Q., Wan, Q., & Li, H. (2021, 4 de Noviembre). Heterogeneity Analysis of the Effects of Haze Pollution on the Health of Left-Behind Children in Urban and Rural Areas in China. International Journal of Environmental Research and Public Health, 18(21), 11596. https://doi.org/10.3390/ijerph182111596