Large clouds of smoke are hovering over Tenerife these days. The spectacular fire that has devastated the Forest Crown from various points of the island has also caused a huge amount of smoke to be emitted into the atmosphere which, when the wind direction is not favourable, also floods the low-lying and even coastal areas of the affected municipalities. That smoke is anything but harmless, and prolonged, continuous inhalation can cause heart and respiratory problems.
This Monday, the skies of the north and south of Tenerife woke up covered by an enormous layer of smoke that had descended the slope during the night, with the katabatic winds, and was facing the sea breeze that pushed the trade wind trying to climb the mountain. The smoke, however, prevailed against the sea breeze and throughout the morning the air became unbreathable. And while the population covered their eyes, nose and mouth as best they could, record concentrations of particles of less than one micron (PM1) were recorded in Canary Islands.
The authorities decreed recommendations for “very unfavorable” air quality. These recommendations included avoiding going outside, carrying out prolonged physical activities, closing doors and windows, and using masks with maximum filtration (FFP2) outside. And it is that this type of pollutant, even smaller than haze – which has already shown its potential to cause various cardiac and respiratory pathologies – in prolonged exposures, of months or years, can trigger heart disease.
The times when the greatest amount of these particles accumulate in the north is at night. At dawn yesterday, the values reached between 200 and up to 453 micrograms per cubic meter of particles of less than one micron at the station located in Balsa de Zamora-Los Realejos (the only one in the north of Tenerife). Concentrations were also high during the night in the south, where the Arafo Mobile Unit registered up to 98 micrograms per cubic meter of PM1 at 03:00 in the morning.
60 times higher than usual
“In the Canary Islands we usually have very few concentrations of this type of PM1 particle,” highlights Sergio Rodríguez, a researcher at the Institute of Natural Products and Agrobiology (IPNA-CSIC). In fact, in other places in the Archipelago where the fire does not exist, the maximum concentration of these particles is barely 6 micrograms per cubic meter, as is the case in Reef (Lanzarote), or 4 micrograms in Breña Baja (The Palm). At the Arafo Mobile Unit, once the wind blew uphill again, the concentrations were 3 micrograms per cubic meter. Therefore, the concentrations registered during this fire are 60 times higher than usual.
Unlike PM2.5, PM1 maximum concentrations are not regulated and monitoring technology is still limited. In the Canary Islands, only 13 stations of the Canary Islands Air Quality Control and Surveillance Network are monitored, but yesterday only the Mercado Central station was collecting data (Gran Canaria), San Antonio-Breña Baja (La Palma), Ciudad Deportiva-Arrecife (Lanzarote) and the Zamora-Los Realejos Raft and the Arafo Mobile Unit (Tenerife). In the last few hours, a Mobile Unit has been installed on the island in La Orotava to reinforce the data provided. In addition to smoke from indoor fires or burning wood, PM1 is also emitted by factories and other industries, vehicle exhaust, and car tires when used. Because human activity makes up the majority of PM1 sources, densely populated urban areas, especially those with busy roads or industrial facilities, are especially prone to PM1 pollution, as well as other types of particulate pollution.
Urban areas are therefore the most affected. A PM1 study that analyzed this pollutant in the city of Delhi, India, between October and November 2020, found average PM1 concentrations of 200 to 300 micrograms per cubic meter throughout the study.
The smaller the diameter of a particle, the more damage it usually causes. And it is that these tiny particles are small enough to penetrate the lung tissue and reach the bloodstream. As Rodríguez explains, these particles “arrive directly to the alveolus and, from there, they pass through the interstitial space and into the bloodstream.” Within months or years, after very long exposure, it can trigger “heart disease.” In a recent study, these types of particles, which are also emitted by cars, “were found in the kidneys of patients.”
In 2017, a study published in The Lancet Planetary Health analyzed ER visits at 28 hospitals in 26 Chinese cities in correlation with PM1 and PM2.5 monitoring data. What he recorded is that with an average concentration of 42.5 micrograms per cubic meter sustained over time, visits to the ER increased, and each increase suffered by just 10 micrograms was enough to prolong the effects for up to two days later.
Although there have not been any major incidents of smoke inhalation in Tenerife, the Primary Care services have noticed an increase in the number of people who come to health centers suffering from an ophthalmological or upper respiratory condition, especially in areas of La Orotava and Guimar. As a result of this circumstance, and seeing the effects of prolonged exposure to these high concentrations of PM1, the use of the mask outdoors is required.
