The air pollution caused by volcanic gases emitted during the eruption in Holuhraun was above the health protection limit for a total of 107 hours in Höfn, Southeast Iceland. Inhabitants in Höfn were subject to air pollution for more hours than in any other community in Iceland, as revealed at a symposium in Reykjavík on the effects of the eruption pollution yesterday.
Höfn also saw the highest levels of sulfur dioxide (SO2), which proved the biggest eruption hazard, picked up in an inhabited area 21,000 µg/m3, in late October, Morgunblaðið reports.
At levels above 2,000 µg/m3—which have been recorded across the country—warnings are issued and people advised to stay inside with the windows closed and heaters on. An hourly concentration of 350 µg/m3 is the limit for the protection of human health in Iceland.
Before the eruption, the highest concentration of SO2 seen in Iceland was 200 µg/m3, measured close to an aluminum smelter, as stated by Environment Agency of Iceland specialist Þorsteinn Jóhannsson, who spoke at the symposium.
Gas pollution was measured for more hours in Reykjavík in Southwest Iceland, 260 km away, than in Reyðarfjörður, 120 km east of the eruption site. On September 6, SO2 levels as high as 498 µg/m3 were even picked up in Ireland, 1,407 km from Holuhraun.
Þorsteinn also stated that the SO2 emitted by the eruption amounted to 20,000-60,000 tons per day, which makes Holuhraun the most gas-intensive eruption in Iceland since the 18th century.
For comparison, Þorsteinn mentioned that the daily SO2 emission by the Alcoa aluminum smelter in Reyðarfjörður is 16 tons per day and the total SO2 emission by all European Union member states is 14,000 tons per day.
Þorsteinn revealed that one day in Akureyri in North Iceland, the SO2 pollution measured above the employment health protection limit for hours and therefore no one should have been working outside that day. However, as the air pollution had come as a surprise, neither companies nor health protection authorities responded accordingly.
The new lava field is still degasing and volcanic gas concentration at the eruption site reached fatal levels one week after the eruption ended in early March.
“Therefore it’s important to continue measuring gas levels so that tourists can travel right up to [the new lava field],” Þorsteinn concluded. People can now travel within 20 meters (66 feet) of the new lava but traversing the lava remains dangerous and banned.
The pollution’s effect on vegetation, lakes and rivers was also discussed at the symposium. Samples taken in all regions have indicated that snow has turned acidic as a result of the volcanic gases.
Prior to the symposium, director of the Department of Civil Protection and Emergency Management Víðir Reynisson told Iceland Review that pollution levels will peak immediately after spring thaw but that it won’t be a lasting problem.
Víðir is confident that come summer, it will be safe to release sheep to the highlands, as is customary in Iceland, and for hikers to drink water from brooks.
The symposium was held by the National Commissioner of the Icelandic Police’s Department of Civil Protection and Emergency Management, the Farmers’ Association of Iceland and the Ministry of Industries and Innovation and Ministry for the Environment and Natural Resources.