Toxic gas fears grow as the La Palma lava flow approaches the sea

The contact of magma with saltwater, expected in the next few hours, can generate explosions and the release of harmful vapours. Maritime authorities have established an exclusion zone off the coast


The steady approach of the La Palma volcano lava to the ocean, which is forecast to happen later this Tuesday (21 September) is worrying the authorities and experts alike because the reaction between lava and saltwater causes toxic clouds of gas to be given off.

For this reason, the Civil Protection service on the island will be intensified when it does because "it can generate explosions and the emission of harmful gases," according to the Pevolca crisis committee (Pevolca).

Maritime authorities have established an exclusion zone at sea, running parallel to the coast and on land security forces will prevent access to the area.

Chemical reaction

When the magma, at a temperature of about a thousand degrees, reaches the sea water, just over twenty degrees, there will be an explosion of steam that will generate a dense white cloud. The extreme heat create causes this plume of steam, but a chemical reaction also takes place and the resulting gas and small particles of volcanic crystals can irritate the skin, eyes and respiratory tract.

Jesús Ibáñez, one of the leading European experts in volcanic seismology and professor of Earth Physics at the University of Granada (UGR), is urging the residents to take precautions to protect themselves from the toxic cloud: “The volume of gases emitted is really very high. Residents have to be very careful because they are very harmful," he adds.

The Canary Island authorities have established a perimeter to prevent access to the areas affected by the volcano cloud.

“People will not be able to go home for a few weeks or months”, predicts the expert. Likewise, the president of the Official College of Geologists (Icog), Manuel Regueiro, also recommends that the local population follow the instructions of the La Palma authorities and do not go near the lava flows.

Hindering the emergency services

Meanwhile Mariano Hernández, president of the Gran Canaria council said, “We ask the population and tourists not to interfere with the work of the emergency services, as happened last night with the evacuations. The roads were blocked and it is dangerous hindering the work of the emergency services.

Satellite images from the European Space Agency have revealed that the ejected magma has washed away 166 buildings and has already covered more than 100 hectares. It is still too early to assess the damage, but volcanologists warn that many days of an eruption may lie ahead.

The Canary Islands Volcanological Institute (Involcan) has carried out new measurements to evaluate and monitor the amount of sulphur dioxide in the atmosphere. The results, on the second day of the eruption, show an emission rate of between 7,997 and 10,665 tonnes per day.