High levels of sulfur dioxide (SO2) from the eruption in Holuhraun were detected at the air quality monitoring station in Grafarvogur at 2 pm. Levels were up to 500 mµ/m3, as stated in a press release from Reykjavík City Council. At levels above 600 mµ/m3 people are advised against engaging in physical activity outside.
It is considered likely that similar levels were also present in other areas of Reykjavík.
The Icelandic Met Office recently started publishing maps showing a calculation of atmospheric concentration of SO2 at ground level as well as gas dispersion forecasts.
Graphs showing pollution levels in different locations are available on the website of the Environment Agency of Iceland.
A map on the website of the Reykjavík Public Health Authority shows the location of pollution sensors in the capital area and the quality of air at each given time.