Volcanic ash cloud – the latest news from SEPA - update 1

date16 April 2010

The Scottish Environment Protection Agency (SEPA) is monitoring the situation regarding the volcanic ash cloud currently affecting the UK and its possible impact on Scotland’s environment.

SEPA has completed preliminary analysis on two dust samples collected in Aberdeen and Lerwick. Preliminary microscopic analysis has shown that the properties of the particles appear to be consistent with the properties of volcanic ash, but further more detailed analysis is required and is currently being undertaken.

SEPA will continue to monitor the situation closely over the weekend and continue to collect samples where appropriate. However, current evidence suggests that the environmental risk will be low.

The Scottish Air Quality Database contains the most up-to-date continuous ambient monitoring information across Scotland. Members of the public can access this information at www.scottishairquality.co.uk.

Potential human health effects

Particulate matter has potential health effects such as causing eye and skin irritation and increased respiratory effects for conditions such as asthma or other lung conditions. Information on possible health effects has been issued by Health Protection Scotland www.hps.scot.nhs.uk. They have said that the levels of particles reaching ground level are likely to be low and should not cause serious harm.

Wider environmental risks

Information suggests that previous historical eruptions have caused few water quality problems. The most common effects are from the suspension of ash on uncovered water supplies such as reservoirs. This may result in a change in turbidity and acidity, although this is generally short-lived (a few hours to days). Such impacts seem to be associated with significant ash falls, eg greater than 3mm.

Whilst the weather remains dry, there will be no impact on the water environment. Should it rain, there may be a slight increase in the acidity of the rain, but there would be a minimal effect on the water environment as much of the rain would land on open land and percolate through the soil.

Volcanic ash can contain fluorine, and the main concern of fluorine poisoning is for livestock, which graze on ash-contaminated grass and feed, but significant deposits are usually required and there is no evidence so far that these will occur. 

Summary

Continuous monitoring of the situation is ongoing but the current available evidence suggests that there is a minimal risk to human health and the wider environment.