Healthier Life website has an article on the volcanic ash:
We’ve all heard the news and some of us may even have been affected by the eruption of the Eyjafjallajökull volcano in Iceland. Yet, most people probably remain unaware that fluoride, from the volcanic ash, has been identified as posing a big risk to human and animal health...
This threat comes from the fluoride, in volcanic ash, contaminating our drinking water and as a result of animals, such as cattle and sheep, consuming ash deposited on grass and soil. With the volcano erupting a second time in a month there are fears that this risk may be bigger than first thought.
See rest of article here.