I understand that the question is in relation to general research in relation to this issue and not to one specific study. Research to date has indicated a suspected correlation between aluminium uptake and Alzheimer's disease; however, there is no conclusive evidence of a causal relationship. The World Health Organisation (WHO) has indicated that "On the whole, the positive relationship between aluminium in drinking water and Alzheimer's disease which was demonstrated in several epidemiological studies, cannot be totally discounted. However, strong reservations about inferring a causal relationship are warranted in view of the failure of these studies to account for demonstrated confounding factors and for the total aluminium intake from all sources."
Council Directive 98/83/EC on the quality of water intended for human consumption puts in place parametric values for certain substances, including aluminium, in order to protect human health from the adverse effects of any contamination — the parametric value for aluminium is 0.2 mg/l. Legislative responsibility for the transposition of this Directive lies with my colleague the Minister for the Environment, Heritage and Local Government.
The Deputy may wish to note that the Report on the Quality of Drinking Water in Ireland for 2004, produced by the Environmental Protection Agency, indicates an overall compliance rate of almost 95% with the aluminium parametric value referred to above.