From Declan Waugh’s FB page

“The data on Fluoride exposure and IQ presented at the Tehran Conference helps to explain Ireland’s ranking of 26th of 34 participating OECD countries for students skills and knowledge in Mathematics in the Programme on International Student Assessment.”

Waugh links to a press release from the Irish Parliament, which clearly refers to the 2009 data, (the 2012 results will not be available until 3 December this year), and then attempts to link Ireland’s results to water fluoridation in that country.
Water’s been fluoridated in Ireland (in urban centres anyway) since the 1970s. For the 2009 PISA results Ireland was significantly below OECD average in Maths, significantly above for science & the ‘reflect & evaluate’ component of literacy, & not significantly different from the average for all other aspects of literacy. In 2006 Irish students’ results for science were significantly above the OECD average, while maths was on the average, and overall literacy was average or above average. It would appear that there was little change between 2000 & 2003 (possible improvement in some areas), & 2003 data appear comparable to 2006.

 
So how likely is it that Waugh’s claim that the decline, particularly in maths, noted in 2009 data is due to fluoridation? Can this really underpin a sudden & recent decline in students’ cognitive abilities? (And why wouldn’t that have been noted earlier, given the duration of fluoridation in that country?) I suspect changes in the Irish economy may have had a greater impact on student performance & the education system in general, considering that they’ve been running austerity budgets since 2008 – budgets which cumulatively have taken 28 billion Euros out of the economy.